PNW 598* October 2007 Commercial Red Raspberry Production

A Pacific Northwest Extension publication Oregon State University • University of Idaho • Washington State University Acknowledgments Regional editors Danny L. Barney, Extension horticulturist, University of Idaho, Sandpoint Research and Extension Center Carol Miles, agricultural systems area faculty, Washington State University, Vancouver Research and Extension Unit Authors Danny L. Barney, Extension horticulturist, University of Idaho, Sandpoint Research and Extension Center Peter Bristow, research pathologist (retired), Washington State University, Puyallup Research and Extension Center Craig Cogger, Extension soil scientist and research soil scientist, Washington State University, Puyallup Research and Extension Center Sheila M. Fitzpatrick, research entomologist, Agriculture and Agri-Food Canada, Pacific Agri-Food Research Centre, Agassiz, British Columbia, Canada John Hart, Extension soil scientist, Oregon State University Diane Kaufman, Extension agent, Oregon State University, North Willamette Research and Extension Center Carol Miles, Extension specialist, Washington State University, Mount Vernon Northwestern Washington Research and Extension Center Timothy Miller, Extension weed scientist, Washington State University, Mount Vernon Northwestern Washington Research and Extension Center Patrick P. Moore, fruit breeder, Washington State University, Puyallup Research and Extension Center Todd Murray, Extension coordinator, Washington State University, Whatcom County Cooperative Extension Hannah Rempel, research technician, Horticultural Crops Research Lab, USDA-ARS, Corvallis, Oregon Bernadine Strik, Extension berry crops professor, Oregon State University Lynell Tanigoshi, entomologist, Washington State University, Mount Vernon Northwestern Washington Research and Extension Center Photo contributors Danny L. Barney, University of Idaho Pete Bristow, Washington State University Ralph Byther, Washington State University Ken Gray Collection, Oregon State University Dave King, Oregon State University Wes McDiarmid, Agriculture and Agri-Food Canada Carol Miles, Washington State University Todd Murray, Washington State University Oregon State University Department of Horticulture Oregon State University Extension Plant Pathology Jay Pscheidt, Oregon State University Bernadine Strik, Oregon State University Lynell Tanigoshi, Washington State University Jim Troubridge, Agriculture and Agri-Food Canada Teresa Welch, Oregon State University Editing Teresa Welch, Oregon State University

This publication replaces Pacific Northwest Extension publication PNW 176. Ordering Information To purchase additional copies of Commercial Red Raspberry Production, PNW 598, please order by title and series number from one of the offices below. Idaho Agricultural Publications College of Agricultural and Life Sciences University of Idaho Moscow, ID 83844-2240 Phone: 208-885-7982 Fax: 208-885-4648 E-mail: [email protected] Web: info.ag.uidaho.edu Oregon Publication Orders Extension & Station Communications Oregon State University 422 Kerr Administration Corvallis, OR 97331-2119 Phone:541-737-2513 Fax: 541-737-0817 E-mail: [email protected] Web: extension.oregonstate.edu/catalog/ Washington Bulletin Office Cooperative Extension Washington State University P.O. Box 645912 Pullman, WA 99164-5912 Phone: 509-335-2857 Toll free: 1-800-723-1763 Fax: 509-335-3006 E-mail: [email protected] Web: caheinfo.wsu.edu Contents

Chapter 1. Commercial Red Raspberry Production i History 1 World and Pacific Northwest production 2 Types of raspberries 2 Red raspberry production systems 3 Raspberries and human nutrition 5 Chapter 2. The Red Raspberry Plant 7 Roots 8 Primocane growth and development 8 Dormancy and cold hardiness 9 Floricane growth and development 10 Flowers and fruit 11 Yield 11 Chapter 3. Cultivar Selection 15 Summer-bearing red raspberries for western Oregon and Washington 16 Summer-bearing red raspberries for locations in and east of the Cascade Mountains 18 Primocane-fruiting raspberries 19 Chapter 4. Plantation Establishment 21 Selecting a site 21 Site preparation 23 Planting stock 24 Row spacing 24 Planting systems 25 Trellis designs 27 Planting 28 Chapter 5. Plantation Maintenance 31 Row management 31 Pruning and training 31 Primocane suppression 33 Mulching 35 Pollination 36 Water management 37 Weed management 40 Cover crops and alley management 45

continues on next page Chapter 6. Plant Nutrition Management 49 Tissue testing 50 Soil sampling 53 Nitrogen 53 Phosphorus 56 Potassium 57 Sulfur 58 Micronutrients 58 Soil pH, acidity, and alkalinity 59 Manure 61 Chapter 7. Raspberry Disease and Nematode Management 63 Diseases that cause symptoms on fruit 64 Diseases that cause symptoms on canes and leaves 65 Diseases that cause symptoms on roots 71 Nematodes 74 Chapter 8. Integrated Pest Management of Insects, Mites, and Slugs 77 Caterpillars: spanworms, leafrollers, cutworms, and loopers 77 Noncaterpillar insect pests 81 Spider mites 85 Slugs and snails 86 Chapter 9. Organic Production 87 Site history 88 Site preparation 88 Planting stock 90 Pest and disease management 90 Obtaining organic certification 90 Chapter 10. Harvesting and Postharvest Considerations 91 Mechanical harvesting 91 Hand harvesting 93 Sanitation concerns 94 Postharvest care 95 For More Information 97 Appendix A. Calendar of Activities 99 Appendix B. Color Plates 101 Chapter 1. Commercial Red Raspberry Production

Chapter 1

Commercial Red Raspberry Production

History chance seedlings. Tradescant's catalog in 1656 mentioned four cultivated variet- Raspberries have been used for mil- ies, including a dark-fruited selection. In lennia for food and medicine. Cato first 1780, Richard Weston described a "twice- mentioned them in pre-Christian texts, and bearing kind," which later would be called Pliny the Elder, in about 45 A.D., wrote of an everbearer, fall-bearer, primocane- the "Ida fruits" that were harvested from bearer, or primocane-fruiter. In 1829, the slopes of Mount Ida in Greece. Rasp- George Johnston's History of English berries were not cultivated at that time, but Gardening listed 23 cultivated raspberry were collected from the wild, primarily for varieties. Named raspberry varieties were medicinal use. first sold in North America by a New York By the 4th century A.D., the Romans nursery in 1771. had begun cultivating raspberries, and Although the fruits were undoubtedly raspberry seeds have been found at the popular for food, medicinal uses remained sites of Roman forts in Britain. The name important. Raspberry leaf tea is an ancient, "Ida" persisted and was used by the taxon- but still popular, herbal infusion. Modern omist Linnaeus to name the European red research has shown that a water-soluble raspberry, Rubus idaeus. Little more was extract from raspberry leaves relaxes written about raspberries until the 1500s, the uterine muscles. Mixtures of rasp- when gardeners in Britain slowly began berry flowers and honey also were used adopting the fruits. By the mid 1600s, as eye ointments and for treating "weak raspberries had become popular in London stomachs." markets. Despite this long history of medicinal As the fruits became more popular, and food use, development of raspberry gardeners began selecting and nam- cultivars (cultivated varieties) has lagged ing superior plants that developed from Chapter 1. Commercial Red Raspberry Production

behind other fruits. Not until the early Types of raspberries 1900s did researchers begin making con- Raspberry fruits can be red, black, pur- trolled crosses, first in North America ple, or yellow. Most commercial raspber- and later in Europe. "Latham" was one ries grown in the Pacific Northwest are red of the earliest cultivars developed using fruited. Red raspberries belong to the rose controlled crosses; it was released by the family (Rosaceae). This family includes Minnesota Fruit Breeding Farm in 1914. other fruit crops such as apples, plums, peaches, black raspberries, blackberries, World and Pacific and strawberries. Northwest production According to bramble expert As raspberry cultivars improved, popu- D.L. Jennings, "Red raspberries are larity of the fruits increased. Today, rasp- widely distributed in all temperate regions berry breeding and commercial cultivation of Europe, Asia, and North America." occur in many parts of the world (Table 1). While the taxonomy is rather complicated, Commercial red raspberry production has European red raspberry forms generally proven especially popular and success- are referred to as Rubus iclaeus and North ful in western Oregon and Washington American forms as R. strigosus. Both are (Table 2), where most of the production diploid, intercross readily to produce fer- goes for processed fruit. Red raspberries tile hybrids, and generally are considered are also a popular crop throughout Idaho subspecies of R. iclaeus L. Other diploid and eastern Oregon and Washington, and tetraploid red-fruited raspberry species where they are grown on small acre- and subspecies also exist. ages and sold mostly through local fresh While R. idaeus and R. strigosus types markets or used by small-scale processors interbreed freely, they exhibit distinctive for high-value, niche products. differences. Rubus idaeus berries have

Table 1. United States and European raspberry product ion.1

Acreage harvested Yield per acre Total production (acres) (pounds) (tons)

1980 1990 2000 1980 1990 2000 1980 1990 2000

United States 6,718 10,991 15,544 3,926 4,730 7,249 13,224 26,062 56,484 Europe (total) 43,825 113,973 112,221 — — — 130,899 202,674 203,760 Bulgaria 8,205 4,555 3,211 1,569 2,010 2,053 6,454 4,590 3,306 France 2,964 3,208 3,609 5,117 4,386 5,326 7,604 7,055 9,635 Germany — 12,844 14,573 — 4,662 5,084 22,704 30,020 37,137 Hungary — 16,673 13,585 — 3,587 3,204 20,420 29,983 21,824 Poland 22,232 26,582 31,089 1,928 2,353 2,809 21,497 31,360 43,779 Serbia and Montenegro — — 33,436 — — 3,687 — — 61,777 Spain — 617 1,543 — 3,560 3,560 — 1,102 2,755 U.K. .9,139 9,633 4,446 5,364 4,377 4,697 24,575 21,136 10,469 'Total reported raspberry production, including red, black, yellow, and purple cultivars. Source: United Nations Food and Agriculture Organization (2005). Chapter 1. Commercial Red Raspberry Production

Table 2. Red raspberry production and prices in Oregon and Washington, 1980-2005.

Acreage Yield per Production utilized Price harvested acre1 (1,000 pounds) ($ per pound) (acres) (pounds) Fresh Processed Total Fresh Processed Oregon 1980 2,100 5,050 600 10,000 10,600 — 0.27 1990 4,200 5,120 500 21,000 21,500 0.88 0.32 2003 2,000 2,600 1,000 4,200 5,200 1.28 0.70 2004 1,900 3,530 1,100 5,600 6,700 1.37 0.76 2005 1,900 3,680 1,300 5,700 7,000 1.55 0.66 Washington 1980 2,800 4,500 2,240 10,360 12,600 — 0.30 1990 4,600 5,000 1,000 22,000 23,000 0.90 0.35 2000 9,500 7,500 4,000 67,250 71,250 1.26 0.31 2003 9,200 7,300 1,400 65,800 67,200 1.67 0.52 2004 9,000 6,700 1,500 58,800 60,600 1.69 0.75 2005 9,500 7,400 1,400 68,900 70,300 1.97 0.53 'Pounds of utilized berries per acre. Unharvested or discarded fruit is not included. Source: Oregon Agricultural Statis- tics Service (2005) and Washington Agricultural Statistics Service (2005). glandless inflorescences and thimble- or Raspberry fruits also may be yellow. conic-shape fruits. Rubus strigosus inflo- Yellow raspberries are the same species rescences have glands and develop into as red raspberries, differing only in fruit round berries. The canes of North Ameri- color. Cultural practices described in this can red raspberries are thinner, more erect, guide apply to yellow cultivars. and better adapted to the harsher climate on this continent than are European red Red raspberry raspberries. Fruit breeders made signifi- cant improvements in raspberry cultivars production systems by crossing North American and European There are two types of cultivated types, producing large, attractive, high- red raspberries—summer-bearers and quality fruits on stout, cold-hardy canes. primocane-fruiters. On summer-bearing Black raspberry cultivars are domesti- raspberries, first-year canes (primocanes) cated forms of Rubus occidentalis, a dip- generally are vegetative. In the second loid species native only to North America. year, fruit is borne in early summer on Although widely distributed in the United the entire length of the canes (now called States and southern Canada, this species floricanes). The crop normally is harvested is less cold hardy than native red raspber- annually. ries and can be found in more southerly Summer-bearing raspberries can be locations. produced in an alternate-year crop- Purple cultivars are hybrids between ping system, however, by removing all black and red raspberries. Black and canes during the dormant season every purple raspberries are grown somewhat other year. This strategy creates alternate differently than red raspberries and are not cropping and noncropping years. Growers discussed in this guide. generally prefer to alternate large blocks, Chapter 1. Commercial Red Raspberry Production

rather than individual rows. Doing so cultivars is inferior to that produced on greatly simplifies plantation management. summer-bearing cultivars. It also can be Mowing the canes every other year difficult to harvest because the newly saves labor costs associated with pruning developing primocanes obscure the fruit- and training. Additionally, material and ing laterals. The latter disadvantage is labor costs for noncropping fields are less more pronounced in western Oregon and than for fields of fruit-bearing canes. Washington, where primocane growth In trials at Washington State Universi- begins earlier than in cooler locations. ty's Vancouver station, 'Willamette' and Interference with floricane harvest by 'Meeker' were tested in alternate-year primocanes is more pronounced in cropping for 6 years (three alternate- primocane-fruiting than summer-bearing year cycles). Primocane suppression (see raspberries. This problem is due to the page 33) was carried out each year to help fact that the tops of the bearing canes in ensure maximum sustained yields. Com- primocane-fruiting cultivars are cut off pared with every-year cropping, however, during the first autumn. The resulting yields were reduced by 60 percent over the floricanes are relatively short and are con- 6-year period. The large yield reductions cealed by the developing primocanes. in alternate-year production generally Managing for a single crop per year on make this practice uneconomical. During primocane-fruiting raspberries reduces periods of low berry prices, however, the pruning labor and other management reduced costs associated with alternate- costs, facilitates harvest, and helps ensure year production may make it feasible for high-quality fall fruits. These advantages, some growers. of course, come at the cost of reduced Primocane-fruiting raspberries (also yields, compared to producing and har- known as fall-bearers, everbearers, or vesting both summer and fall crops. primocane-bearers) produce relatively In greenhouse production or in regions large crops at the tips of the primocanes with mild climates, fruiting of primocane- in late summer and fall. The following fruiting cultivars can be delayed by sum- summer, they also produce a crop on the mer tipping of the primocanes to produce lower sections of the floricanes from June off-season crops from late fall through late through July, at the same time as summer- winter. bearing cultivars. Greenhouses and hoophouses covered Cropping twice each year may reduce with plastic film also are used to grow fall yields due to competition between the raspberries in regions where the climate floricanes and primocanes. Some growers does not favor raspberry production. prune all canes to the ground in early Hoophouse and greenhouse production is spring and produce only a primocane crop. not discussed in this publication. Some people believe that the quality of the summer crop on primocane-bearing Chapter 1. Commercial Red Raspberry Production

Raspberries and Table 3. Composition of fresh red raspberries. human nutrition Amount per 100 grams Raspberries have long been valued for Constituent of fresh fruit their medicinal and nutritional benefits. Water (percent)1 84.2 % With today's interest in natural foods Calories1 57 and healthy diets, raspberries' popularity Protein1 i.2g 1 remains strong. Recent research supports Fat 0.5 g Carbohydrate1 13.6 g long-held beliefs that raspberries are a 2 Fiber 6.5 g particularly healthy part of the human Calcium1 22 mg diet. The fruits contain little fat and are Iron1 0.9 mg rich sources of dietary fiber, vitamin C, Magnesium2 22 mg and potassium. They also are rich in anti- Phosphorus1 22 mg Potassium1 168 mg oxidant capacity and contain compounds 1 thought to be important for vascular health Sodium 1 mg Vitamin A1 130 International Units and cancer prevention, including procyani- Ascorbic acid (Vitamin C)1 25 mg dins and ellagic acid. Table 3 summarizes Niacin1 0.9 mg some of the nutritional characteristics of Riboflavin (Vitamin B2)1 0.09 mg red raspberries. Thiamine (Vitamin B1)1 0.03 mg Total anthocyanins3 (cyanidin 3-glucoside equivalent) 65 mg Total phenolics3 (gallic acid equivalent) 517 mg Antioxidant capacity1 (ORAC, Trolox equivalent) 2,400 pmol 1B.K. Watt and A.L. Merrill. 1963. Composition of Foods. USDA Agricultural Handbooks. 2USDA. 2005. National Nutrient Database for Standard Reference, Release 17. 3L. Wada and B. Ou. 2002. Antioxidant activity and phenolics content of Oregon caneberries. J. Agric. Food Chem. 50:3495-3500. Chapter 1. Commercial Red Raspberry Production Chapter 2. The Red Raspberry Plant

Chapter 2

The Red Raspberry Plant

Raspberries live for many years. Floricanes Although the canes are biennial and live for only 2 years, the roots are perennial. Canes form and elongate only during their first year, when they are called pri- mocanes. In their second growing season, canes are called floricanes. Floricanes do not elongate, but develop lateral fruiting shoots. Except for the planting year, or when floricanes are pruned out in some fall-bearing production systems, both Primocanes primocanes and floricanes are present simultaneously in a planting. A typical red raspberry plant is shown in Figure 1. Red raspberry plantings generally have a commercially productive life of less than 10 years to as long as 20 years in western Oregon and Washington, depend- ing on location. Rotations of 8 to 10 years are common in harsher climates east of the Cascade Mountains or where certain Rhizome viruses are present. Roots Figure 1. A raspberry plant during early summer showing newly formed primocanes and floricanes formed during the preceding growing season. The leaves and fruits have been removed to show the canes and fruiting laterals more clearly. Chapter 2. The Red Raspberry Plant

Roots high levels of nitrogen can increase inter- node length. Internode length also tends Raspberries have an extensive root to vary along the length of the cane, with system consisting of many fibrous, small- nodes being closer together at the tips of diameter roots. Roots have been found to the canes. depths of 6 feet in well-drained soils, but 70 percent of the roots generally are in the Summer-bearing raspberries upper foot of soil, with 20 percent lying Canes on these cultivars grow 6 to 1 to 2 feet deep. In related studies, 64 per- 13 feet tall, depending on the cultivar, cent of the water used by red raspberries production practices, and environmen- was found in the top 2 feet of soil. tal conditions. Primocanes generally are Roots start growing in the spring after vegetative the first year and bear fruit the bud break. If water is adequate, most root second year on the entire length of the growth occurs in midsummer, but growth floricane. continues into the fall after top growth has Flower bud initiation (flower formation stopped. Roots produce shoot buds at ran- for next year's crop) occurs in late summer dom locations. These shoots grow to the as the days grow shorter and temperatures surface and become primocanes. become cooler. This process starts at the tip of the primocane and progresses to the Primocane growth base of the cane. The buds at the very base and development of the cane and those just under the soil do not initiate flower buds and serve as a Primocanes are produced from buds at source of new primocanes the following the floricane base in a section called the spring. crown (the perennial base of the plant) or Primocanes seldom branch unless the from buds on roots. Primocanes produced apical bud is damaged. During long, hot from the roots are known as suckers and summers and autumns, the buds at the tips usually are less vigorous than those pro- of some cultivars break and produce fruit- duced from the crown. ing laterals in the fall. The cultivar 'Wil- Primocane growth or "emergence" lamette' is more prone to primocane tip starts in the spring, usually in early April fruiting than 'Meeker,' for example. This in western Oregon and Washington and crop is always small and is not harvested as late as mid-May in eastern regions of commercially. If the tip portion of the pri- the Pacific Northwest. Primocanes grow mocane fruits in the fall, this section of the rapidly from spring until the hotter days of cane will die and will not produce fruit the summer. They continue to grow in height following summer. more slowly until cold fall weather limits their development. Primocane-fruiting raspberries Primocanes produce leaves and axillary Primocane-fruiting raspberries gener- buds at slight swellings called nodes. Red ally produce shorter canes than summer- raspberries generally have clusters of one bearing cultivars, averaging about 4 to to three buds at each node. 6 feet in height. Fruiting laterals also are The internode length (distance between shorter than those of summer bearers. nodes) depends on the cultivar, light expo- Flower bud initiation begins at the tip sure, and nutrition. Internodes are longer of the primocane in late spring to early in shady conditions than in full sun, and summer and progresses downward. Unlike Chapter 2. The Red Raspberry Plant

summer-bearing cultivars, however, flower normal growth and development. Because bud initiation does not depend on day chilling requirements depend greatly length and temperature, but rather on the on variable environmental conditions, physiological age of the cane. Research they are hard to predict exactly. Chilling with 'Heritage' has shown that flower bud requirements generally range from 800 to initiation begins when canes have pro- about 1,400 hours for cultivars grown in duced about 50 nodes and then proceeds the Pacific Northwest. down the canes for about 10 to 12 nodes. Extended periods of temperatures The number of nodes that form fruiting between 32 and 450F are ideal for chilling, laterals during the first season depends on although chilling is reported to occur in the cultivar. raspberries at 280F. Warm weather during In western Oregon and Washington, winter can make plants lose some accumu- flowers on primocanes generally open in lated chilling hours. July, and the fruiting season runs from late Based on observations, 'Meeker' July through October, depending on the requires more chilling hours than 'Wil- cultivar. In and east of the Cascades, flow- lamette.' Following mild winters, during ers typically begin opening in August or which the chilling requirement has not September, with harvest from late August quite been satisfied for 'Meeker,' bud until October. Weather can have a major break in the spring can be relatively poor. impact on fruiting season as it affects pri- Red raspberries are relatively cold mocane growth and flowering time. hardy compared to black raspberries and Those portions of the primocanes that trailing blackberries. Nonetheless, red develop fruit die by the following spring. raspberries can be injured when tempera- Buds farther down the primocanes con- tures of 0 to -10°F are accompanied by tinue to develop into the fall and again drying winds that desiccate the canes. during the following spring, and they pro- Not all tissues within the canes or buds duce a second crop of fruit on laterals in are equally cold hardy. Cane tissues have early summer. The basal buds remain veg- been found to be 3 to 27°F more cold etative and are a source for new primocane hardy than buds, depending on the culti- growth in the spring. var, time of year, and environmental fac- tors. Within buds, the tissues at the base of Dormancy and the bud (where it attaches to the stem) are less cold hardy than the tissues within the cold hardiness bud scales. Also, raspberries bear both pri- In autumn, leaves turn yellow or yel- mary and secondary buds. Primary buds, lowish-red, dry up, and fall from the when undamaged, produce most of the primocanes. Before the leaves fall, some crop and are less cold hardy than second- nutrients and biochemicals move from the ary buds. leaves to the canes and roots, where they The degree of cold hardiness varies are stored for next year's growth. The pri- throughout the year. Flowers and actively mocane stems and buds remain alive and growing tissues may be killed at around enter a condition called dormancy, or rest. 28°F. As plant senescence and winter Once plants enter dormancy, a certain acclimation begin in fall, hardiness slowly number of chilling hours, generally con- 0 increases. Maximum resistance to freezing sidered to accumulate at or below 45 F, injury is found in fully acclimated canes are required before the plant can resume Chapter 2. The Red Raspberry Plant

exposed to extended, continuous, non- the tops of the arcs, compared to topped lethal, subfreezing temperatures. Through- canes, making this section of the canes out the Pacific Northwest, maximum cold more prone to cold damage. On the other hardiness is reached from about mid- hand, once chilling requirements have December to early January. been met, topping canes after a warm spell Cold hardiness in raspberries is quite and before a period of subfreezing tem- complicated, however, and relative cold peratures can increase cold injury. hardiness of different cultivars varies depending on the time of year and weather Floricane growth conditions. Some cultivars acclimate early and deacclimate early, while others accli- and development mate and deacclimate later. In November, When growth begins in the spring, the for example, 'Meeker' and 'Willamette' overwintered primocanes become flori- are some of the least cold-hardy cultivars, canes. Floricanes do not increase in length, while 'Chilliwack' is much more cold but buds break along the canes, producing hardy. By February through March, fruiting laterals. 'Meeker' and 'Willamette' are more cold The length of the fruiting laterals and hardy than 'Chilliwack.' Similar differ- the extent of bud break vary by cultivar. ences in relative cold hardiness as a func- Research in the Pacific Northwest has tion of season can be observed with other shown that 'Meeker' never has 100 per- cultivars. cent bud break. Generally, only about Once chilling requirements have been 40 to 59 percent of the buds break. In met, relatively short periods of warm tem- some cultivars, more than one bud some- peratures can decrease the canes' cold har- times breaks at a node, producing more diness. For example, an unusually warm than one lateral per node. January can cause canes to deacclimate or Fruiting laterals produce leaves and lose some of their cold hardiness. If that flowers. The number of flowers on a warm spell is followed by subfreezing lateral depends on the cultivar and is temperatures, the canes can be injured. influenced by environmental conditions. The seriousness of the injury depends on 'Meeker,' for example, typically produces many factors, including cultivar, when 9 to 16 flowers per lateral. the warm spell occurs, how long it lasts, The inflorescences (flower clusters) at how high temperatures rise, how rapidly the tips of the laterals develop and open and how low temperatures drop, how before those nearer the cane. Within an long the low temperatures last, and cul- inflorescence, the primary flower at the tip tural practices, such as weed control and opens first. fertilization. The range in flower opening times, The tips of canes deacclimate more coupled with slightly earlier emergence quickly and are more likely to be dam- of laterals at the tip of the cane, causes aged by cold than tissues farther down fruits to ripen over about 30 days for most the stems. Buds on the upper portions of summer-bearing cultivars grown in the the canes also break earlier in the spring Pacific Northwest. In some cultivars, rip- than those on the basal portions. Arc-cane ening continues for as long as 55 days. training (see "Managing primocane tops," Following fruit harvest, floricanes page 32) can promote earlier bud break at start to senesce. As they die (from early August to early September), they export

10 Chapter 2. The Red Raspberry Plant

1 to 2 grams of nitrogen per plant to the firmness, however, decreases during the crown and roots. This rate equals about later stages of fruit maturation. Fruit firm- 4 to 8 pounds of nitrogen per acre. For this ness is also cultivar-dependent. Particu- reason, it is best to delay floricane removal larly for fresh fruits destined for shipment until fall, rather than removing canes to distant markets, raspberries may be immediately after harvest, unless earlier harvested mature, but not fully ripe, when removal is desirable for disease manage- they are still firm enough to ship well. ment (see "Removing spent floricanes," page 31). Yield The number of berries and individual Flowers and fruit berry weights determine total yield. Fac- Red raspberry flowers have five green tors that influence the number of berries sepals at the base and five white petals. are: (1) the number of fruits per lateral, Many stamens (male pollen-producing (2) the number of fruiting laterals per parts) are arranged around a central, white cane, and (3) the number of canes per acre. receptacle containing many pistils (female Berry weight is influenced by the number fruit-producing parts). The receptacle is of drupelets per berry and drupelet size. called a torus. Total yield includes all fruits that form Technically speaking, a raspberry fruit on the plant. In practice, many fruits are is not a berry. A berry contains several to not harvested due to disease, pest, or phys- many seeds lying together within the pulp ical damage. In addition, some acceptable (blueberries and grapes, for example). A fruits fall to the ground during harvest. drupe, in contrast, is a fruit containing a single seed or pit (for example, cherries Number of fruits per lateral Many factors interact to determine how and plums). Raspberries are aggregate many fruits will form per lateral. These fruits made up of many drupelets, each of factors include the following: which contains a single seed and remains firm and intact during harvest. For conve- • Location of the lateral on the cane nience, raspberry fruits are referred to as • Percent fruit set (the number of flowers berries throughout this guide. that develop into fruits) Raspberry drupelets are arranged spi- • Cane diameter—Larger diameter canes rally around a receptacle. When picked, produce more fruits per lateral. the raspberry separates from the recep- • Competition with other fruits and tacle, producing a hollow, thimble-shape laterals on the same plant for water, fruit. How easily the fruits slip from the nutrients, carbohydrates, and plant receptacle depends on the cultivar. growth regulators—Reducing competi- Raspberry fruits require about 30 to tion through primocane suppression 35 days to mature after pollination. The (removing the first flush of primocanes fruits increase in size at a fairly constant in the spring) and managing the num- rate until about 4 to 5 days before matu- ber of canes per foot of row or per hill rity. During this final stage of ripening, increases the number of fruits per lateral berries rapidly increase in size. (see Chapter 5). This effect is especially To attain maximum productivity, flavor, pronounced at the base of the floricanes. and sweetness, raspberries must reach full maturity and full size before harvest. Fruit • Light intensity —Shading by overly dense canopies reduces flower bud

11 Chapter 2. The Red Raspberry Plant

initiation on primocanes, reducing the • Plant age number of flowers per lateral for next • Cane vigor—Cane vigor depends on the year's crop. cultivar and age of the planting. Plant- Number of fruiting ings become more vigorous and cane numbers increase as the plants mature. laterals per cane Full crops normally are attained by the Factors that influence the number third growing season. of fruiting laterals per cane include the following: • Pruning system—Some growers reduce the number of canes per foot of row • Winter pruning practices—Topping when winter pruning. Primocane sup- reduces the number of nodes (potential pression also reduces the number of fruiting laterals) per cane. canes per acre. • Cane vigor (growth rate) —Vigor influ- • Cultural practices—Practices such as ences internode length. If internodes are irrigation and fertilization affect vigor long, there are fewer nodes or laterals and cane number. per foot of cane length. Internode length increases in response to shade or high Number of drupelets per berry soil nitrogen concentrations. The number of drupelets per berry • Percent bud break—Bud break may be is determined by how many ovules are influenced by cane length, cultivar, and fertilized. Pollination and subsequent fer- limiting factors such as lack of suffi- tilization of the ovules are influenced by cient chilling, winter injury, mechanical weather conditions during bloom, nutrient damage, or disease. status, disease, and insect damage. Cold, wet, and rainy weather greatly • The number of laterals per node—Some reduces bee activity, particularly for cultivars produce as many as three later- als per node. Multiple laterals usually domestic bees. Besides reducing bee for- produce fewer fruits per lateral, but aging, rain can dilute the stigmatic fluid often more fruits per node, than single on the pistils and, thereby, reduce fruit set. Cold temperatures also affect the plant laterals. directly. Even if a flower is pollinated, Number of canes per acre temperatures below about 60oF slow pol- The number of canes per acre depends len germination and pollen tube growth. on the following: This problem is less common in raspber- • In-row and between-row spacing ries, however, than in blueberries, cur- rants, and other fruit crops that bloom in • Cultivar—Cultivars differ significantly early spring. in vigor, an important point to consider Raspberry bushy dwarf virus, which in cultivar selection. Selecting cultivars is pollen-borne, reduces the number of that are vigorous and productive under drupelets that develop on the berries, your cultural and environmental condi- thereby causing "crumbly" fruits that do tions is an important step in ensuring not hold together well. success.

12 Chapter 2. The Red Raspberry Plant

Drupelet size adversely affected, the plant tends to Two berries that have an identical num- respond in ways that offset the potential ber of drupelets may differ in fruit size yield reduction. If the number of buds per or weight. For example, drupelet size is cane is reduced by topping, for example, affected by cultivar. Water stress (insuf- the remaining laterals tend to bear more ficient irrigation, for example) also can fruits. Topping also can result in a higher reduce drupelet size and thus berry weight. percentage of bud break on the remaining nodes. Similarly, removing some flori- Interactions among canes in a hill increases the percentage yield components of bud break on the remaining canes and Red raspberries have great capac- maintains yields in 'Meeker.' ity to compensate for changes in yield components. If one or more factors are

13 Chapter 2. The Red Raspberry Plant

14 Chapter 3. Cultivar Selection

Chapter 3

Cultivar Selection

Selecting appropriate cultivars is criti- is considered to be among the most cold- cal to successful raspberry production. The hardy cultivars. Inferior flavor and other Pacific Northwest is home to an incred- undesirable fruit qualities, however, make ibly diverse range of topography and cli- it a poor commercial selection. 'Killar- mates, from USDA plant hardiness zone ney,' a sibling of 'Boyne,' and many other 9 on southwestern Oregon's mild coast to cultivars have been tested in Idaho and zone 5 in many of Idaho's fruit-growing produced commercially acceptable fruits regions. Cultivars adapted to one region following temperatures of -24 to -30oF. may perform poorly or fail to survive in Disease resistance is another impor- another. tant consideration. Some cultivars are When choosing cultivars, particularly extremely susceptible to Phytophthora root for colder sites in and east of the Cascade rot, for example, and can be especially dif- Mountains, carefully consider cold hardi- ficult and expensive to produce. ness. Study long-term climate records for Marketing is another factor to consider. your immediate area to determine how Some cultivars are best suited to fresh much cold hardiness the crop will need markets, and some are poorly suited for and during what times of the year cold commercial production. Fruit processors hardiness will be required. Select cultivars typically accept only certain cultivars. that match those requirements. Generally, Before selecting cultivars, identify primary cultivars that enter dormancy early and and secondary markets and the standards come out of it late are the most reliable in crops must meet. cold climates and most resistant to late- Finally, some raspberry cultivars are winter or early-spring freezing injury. machine harvestable, while others must be Cold hardiness, however, is not the only picked by hand, an expensive and labor- factor to consider. 'Boyne,' for example. intensive process. Cultivars that are suited

15 Chapter 3. Cultivar Selection

to machine harvest generally have flex- responses to different growing condi- ible, medium-length fruiting laterals. Fruit tions. It produces large, medium-red to borne on short or long laterals does not dark, early-season fruit with a harvest separate from the receptacles easily during season similar to that of 'Willamette' and machine harvesting, and brittle laterals can 'Malahat.' Fruit is relatively low in sugar break before the fruit separates. Cultivars and acidity, resulting in an excellent fla- suited for machine harvest also produce vored, well-balanced, mild fruit. The fruit fruits that slip easily from the receptacles. does not release readily until fully ripe, Many raspberry cultivars have been so 'Cascade Dawn' is recommended for named and released. Some older cultivars local fresh market uses. 'Cascade Dawn' are still popular with commercial growers, exhibits some field tolerance to Phytoph- while others have been replaced by newer, thora root rot. Although it is not as root- better-performing, or more marketable rot-tolerant as 'Cascade Delight,' it is varieties. The following lists provide guid- much more tolerant than 'Willamette' and ance in selecting cultivars suited to your 'Malahat,' other early-season cultivars. It site, market, and production practices. has not tested positive to RBDV and may Unless specifically noted, all cultivars are be immune. susceptible to raspberry bushy dwarf virus 'Cascade Delight' is a new release (RBDV). from the Washington breeding program, and there is limited information on its Summer-bearing red range of responses to different growing conditions. It produces large, medium- raspberries for western red fruit with excellent flavor. The fruit Oregon and Washington is larger and firmer than 'Tulameen' and 'Cascade Bounty' is a new release ripens at about the same time. 'Cascade from the Washington breeding program, Delight' fruit is best suited to fresh uses. and there is limited information about its In some growing conditions, 'Cascade responses to a range of growing conditions Delight' may be more susceptible to fruit and production practices. It is extremely rot than other cultivars. During 2005 in productive, producing large quantities of western Oregon, individual drupelets medium-size, bright-colored, tart fruit. appeared more susceptible to Botrytis The harvest season is similar to 'Meeker.' infection than those on other cultivars. In In field and greenhouse tests, 'Cascade tests on sites heavily infested with Phy- Bounty' has been extremely tolerant to tophthora, 'Cascade Delight' did not show Phytophthora root rot. 'Cascade Bounty' any symptoms of root rot. Unless fertil- seems to be machine harvestable, although ity is controlled, plants can become very machine-harvested fruit may not be suit- large, with large amounts of foliage and able for individually quick frozen (IQF) long laterals that can break under their production. Although it has not been tested own weight. The long fruiting laterals for winter hardiness, based on its parents, are subject to breakage during machine 'Cascade Bounty' may be very winter harvesting, so 'Cascade Delight' is recom- hardy. mended only for hand harvesting. 'Cascade Dawn' is a new release 'Chemainus' is a new release from the from the Washington breeding program, British Columbia breeding program, and and there is limited information on its there is limited information on its range of

16 Chapter 3. Cultivar Selection

responses to different growing conditions. well-drained sites, it can be high yielding, It produces medium-size, bright red, firm but it is very susceptible to root rot. The fruit with good flavor. The fruit ripens in fruit ripens early in the season, 1 week midseason and is suitable for processing earlier than 'Meeker' and slightly earlier and fresh market uses. It is well adapted to than 'Willamette.' The postharvest shelf machine harvesting and IQF. life is good. 'Malahat' can be machine har- 'Coho' is a newer release from the Ore- vested, but the fruit is best suited to hand gon breeding program, and there is limited harvesting for the fresh market. information on its range of responses to 'Meeker' is the most widely grown different growing conditions. It produces raspberry in the Pacific Northwest, mak- large, medium-colored fruit with good ing up approximately 70 percent of com- flavor. The fruit ripens late in the season, mercial plant sales. It has medium to large after 'Meeker.' 'Coho' machine harvests fruit, medium-red color, excellent flavor, well, and the machine-harvested fruit can and is higher yielding than 'Willamette.' be used for IQF berries. The fruit also is The fruit ripens mid- to late season, is suit- suited to fresh use or freezing. 'Coho' is able for freezing, and fair for canning and susceptible to root rot and, reportedly, preserves. Once the plant is established, crown gall. it shows a slight tolerance to root rot. 'Cowichan' is a new release from the Although suitable to machine harvesting, British Columbia breeding program, and the long fruiting laterals may break. there is limited information on its range of 'Qualicum' produces large, firm, responses to different growing conditions. medium- to light-red fruit with good fla- It produces medium to large, light-colored vor. The fruit ripens mid- to late season fruit with acceptable flavor. The fruit rip- and is suitable for fresh and some process- ens mid- to late season and is suitable for ing uses. Unless fertility is controlled, processing and fresh markets, although plants can become very large, with large softness may limit its use. It is adapted amounts of foliage. Because of its vigor, it to machine harvesting. On some sites, can be difficult to machine harvest. 'Qua- 'Cowichan' seems to be susceptible to root licum' has good winter hardiness, but it is rot. It has not tested positive for RBDV very susceptible to root rot. and may be immune. The plants are vigor- 'Ttolameen' produces large, attractive, ous, establish well, and produce an abun- glossy, medium-red fruit with excellent dance of new canes each year. flavor. It has a long fruiting season with 'Esquimalt' is a new release from the a midpoint of harvest similar to that of British Columbia breeding program, and 'Meeker.' It is susceptible to root rot. The there is limited information on its range of postharvest shelf life is good, but the fruits responses to different growing conditions. reportedly are not well adapted to shipping It produces very large, light-colored, late- long distances. 'Tulameen' can be machine season fruit. In some years, the skin of the harvested, but its fruits are best suited to fruit is somewhat thin, causing packaged hand harvesting for the fresh market. fruit to "bleed" during shipping. 'Esqui- 'Willamette' has medium-size, dark red malt' is best suited to hand harvesting for fruit with good flavor. 'Willamette' plants fresh uses. It is very susceptible to root rot. usually are smaller than those of most cul- 'Malahat' produces large, firm, light- tivars. The fruit ripens early in the season, colored fruit with acceptable flavor. On 1 week earlier than 'Meeker.' 'Willamette'

17 Chapter 3. Cultivar Selection

is susceptible to root rot, but immune to 'Killarney' produces dark red, RBDV. It is less cold hardy than 'Meeker.' medium-size, firm fruit with fair to good 'Willamette' machine harvests very well, flavor. The berries are suitable for fresh but yields are lower than those of most use, but not for processing. The canes other cultivars. The fruit is well suited for are spiny, medium-size, sturdy, and very canning and juice, but the dark color is cold hardy. 'Killarney' is among the most less desirable for IQF use. vigorous and reliable cultivars in northern Idaho trials. It is moderately resistant to Summer-bearing red Phytophthora root rot. 'Nordic' is cold hardy, shows some raspberries for locations resistance to the aphid vector of raspberry in and east of the mosaic virus, and is moderately resistant Cascade Mountains to Phytophthora root rot. A light fall crop Growing regions in and east of the of about 1,000 lb per acre is borne on the Cascade Mountains are significantly primocanes in mid-September but often colder and have shorter, cooler growing is lost to fall frosts in short-season areas. seasons than those in western Oregon and Nordic is best grown as a summer-bearing Washington. Adaptability to cold winter crop in short-season areas, where it has temperatures and widely fluctuating tem- proven very productive. The fruit is excel- peratures in late winter and early spring is lent for freezing. an important characteristic on cold, short- 'Nova' is a cold-hardy, early-season season sites. Because of greater climatic cultivar that performed very well in south- variability and the emphasis on local, fresh central Idaho trials. The plants establish markets, cultivar popularity differs greatly quickly and bear large, early yields. The from one region to another. Most of these berries are small to medium size, moder- cultivars are better adapted to hand than ately firm, and have a tart flavor. machine harvest. 'Qualicum' was described under west- 'Algonquin' is a midseason, cold-hardy ern Oregon and Washington cultivars. It variety that produces medium to large performed reasonably well in south-central fruit with excellent flavor. In south-central Idaho trials, although its root rot suscepti- Idaho trials, the fruit tended to be smaller bility could create challenges for commer- than that of other cultivars. The fruit is cial growers. suitable for fresh and processing uses. It is 'Reveille' is an early-season cultivar moderately resistant to Phytophthora root that is productive, vigorous, upright, and rot. suckers freely. The fruit is large, bright 'Festival' produces midseason berries red, somewhat soft, and has a good, tart that are firm, medium-size, and have good flavor. This cultivar was developed for quality. The flavor is mild and lacks sweet- U-pick and market garden production. ness. The berries are suitable for fresh or 'Reveille' is cold hardy and tolerates fluc- processing uses. 'Festival' is cold hardy tuating spring temperatures. It is moder- and adapts to a range of climatic condi- ately resistant to Phytophthora root rot. tions. It reportedly is immune to raspberry 'Skeena' berries are medium to large, mosaic virus, tolerant of spur blight, and bright red, and fairly firm. The fruit is moderately resistant to Phytophthora root sweet, flavorful, and suitable for fresh or rot. processing uses. The canes are vigorous Chapter 3. Cultivar Selection

and productive, but are very susceptible to 'Autumn Britten' has the same parents Phytophthora root rot. Although popular as 'Autumn Bliss' and shares many of the for its flavor, 'Skeena' can be difficult to same characteristics. It produces large, grow over the long term because of its root early-season berries that are better shaped rot susceptibility, and it is questionable for than 'Autumn Bliss,' although production commercial production. It is listed here may be less. only because of its past popularity. 'Caroline' is a release from Maryland, 'Souris' is cold hardy and ripens early and there is limited information on its in the season. The berries are medium size, performance in the Pacific Northwest. It have excellent flavor, and are suitable for produces large, attractive, midseason fruit, fresh or processing uses. It is moderately 7 to 19 days before 'Heritage,' and it is resistant to Phytophthora root rot. used for the fresh market. 'Caroline' plants are vigorous and establish well. Primocane-fruiting 'Chinook' is a recent release from the Oregon breeding program, and there raspberries is limited information on its range of Fall frosts and fruit rot due to wet con- responses to different growing conditions. ditions limit the production of fall-bearing It has the same parents as 'Summit' and raspberries in cooler, short-season loca- shares many of its sibling's characteris- tions. For short-season locations, early- tics. 'Chinook' is productive and bears ripening cultivars, such as 'Summit' and early in the season, about the same time 'Autumn Bliss,' are preferred. as 'Autumn Bliss.' Determining when 'Anne' is a yellow-fruited, fall-bearing the fruit is fully ripe for picking can be raspberry. Information on its performance difficult. The fruit is very large, with fair in the Pacific Northwest is limited. It rip- flavor, and is used for the early-fall fresh ens with 'Caroline,' about 1 to 2 weeks market. In field tests, 'Chinook' proved before 'Heritage,' and produces large ber- tolerant to root rot. It bears a heavy fruit ries with good flavor. 'Anne' reportedly load close to the ground and requires is susceptible to fruit rot and may benefit trellising. from growing under hoop houses or other 'Dinkum' was developed in Australia. protective structures. It produces large, good-flavored fruit that 'Autumn Bliss' produces large ber- can darken as the season progresses. The ries early in the season, with berry size berries begin ripening a few days after decreasing as the season progresses. Ber- 'Autumn Bliss' and are used for the fresh ries produced later in the season may be market. 'Dinkum' reportedly is susceptible coarse. The fruit has acceptable flavor to root rot. and is medium red, but can become dark 'Heritage' produces medium-size, and may be soft. This cultivar is one of firm fruit that has good flavor. The berries the earliest ripening primocane-fruiting begin ripening in late August or Septem- raspberries, ripening 10 to 14 days before ber in cool, short-season locations and, 'Heritage.' Because of the long fall pro- in many years, production is limited by duction season, it can be very productive. deteriorating fall weather. 'Heritage' is 'Autumn Bliss' is used for the early-fall used for the mid- to late-season fresh mar- fresh market and is a good choice for east- ket. 'Heritage' is well-adapted to western ern Pacific Northwest sites. Oregon and Washington. In and east of

19 Chapter 3. Cultivar Selection

the Cascade Mountains, production is best for the early-fall fresh market. In field limited to the warmest, longest season tests, 'Summit' proved tolerant to root rot. locations. It is a good primocane-bearing cultivar for 'Summit' produces small to medium- cool, short-season locations. size fruit early in the season. As the har- 'Golden Summit' is a naturally occur- vest progresses, the berries decrease in ring sport of 'Summit' that produces gold- size and may appear coarse. Fruit size apricot colored fruit. Other plant and fruit generally is smaller than that of 'Autumn characteristics are similar to 'Summit.' Bliss,' and the berries ripen at about the The color can be genetically unstable, and same time. The berries are firm, have reversions to red fruit reportedly are com- acceptable flavor, and are medium red, but mon. Fruit quality does not seem to be as they may become dark. 'Summit' is used good as that of 'Anne.'

20 Chapter 4. Plantation Establishment

Chapter 4

Plantation Establishment

Selecting a site not accumulate as rapidly at subfreezing temperatures or at temperatures much Selecting an appropriate site is critical above 450F. for successful red raspberry production. Minimum winter temperatures are Fortunately, red raspberries are highly also a factor to consider. Cold hardiness adaptable to a wide range of soils and is extremely important in and east of the climates. Nonetheless, factors such as cli- Cascade Mountains, but less so in western mate, soils, and topography should be con- Oregon and Washington. sidered carefully when choosing a planting Western Oregon and Washington pro- site. vide excellent climates for raspberries. Climate Average minimum winter temperatures Red raspberry cultivars are available range from about 250F in southwestern that are adapted to climates as different Oregon to 10oF in northwestern Washing- as the hot southeastern United States, the ton (USDA plant hardiness zones 8-9). cool western Pacific Northwest, and the Winter injury can occur, however, follow- cold Cascade Mountain and Rocky Moun- ing long, warm autumns that interfere with tain ranges. Red raspberries perform best, plant acclimation, during unusually cold however, in areas with relatively dry sum- winters, or where particularly cold-tender mers, warm days, and cool nights. cultivars are grown. Raspberries are temperate-zone plants Growing seasons in and east of the that require a period of winter dormancy. Cascade Mountains are cooler and shorter Depending on the cultivar, approximately than those in the western Pacific North- 800 to 1,400 hours of exposure to tem- west, and winter temperatures are colder. peratures below 450F are needed to meet Fruit-growing regions in eastern Oregon chilling requirements. Chilling units do and Washington and throughout Idaho

21 Chapter 4. Plantation Establishment

experience average minimum winter tem- nutrient management can be more difficult peratures from -5 to -30°F (zones 4-6). on such soils. Cold temperatures are particularly trouble- Heavy silt and clay soils and poorly some when they are accompanied by dry- drained soils of any texture create seri- ing winds. ous challenges in growing raspberries. Summer climatic conditions also play Wet soils greatly aggravate diseases such a role in raspberry cultivation. Hot, dry, as Phytophthora root rot, the most seri- windy weather during early summer can ous root disease in the Pacific Northwest. retard cane growth and cause berries to Avoid these soils for raspberry production. become soft and seedy. Excessive heat Also avoid severely eroded soils; they tend during ripening can cause soft, poorly to be shallow, low in organic matter, and colored fruit and increase the likelihood of subject to further erosion. sunscald on the berries. Raspberries tolerate a range of soil acid- Because of the wide range of climates ity, with an ideal soil being slightly acidic in the tristate area, cultivar selection is (pH between 6.2 and 6.8, with a lower important. See Chapter 3, "Cultivar Selec- limit around 5.6). Lime can be used to tion," for cultivar descriptions. raise soil pH if pH is less than 5.6. Alkaline soils (pH above 7.0) can cre- Topography ate micronutrient problems, particularly Topography is an important consider- iron chlorosis. Sulfur can be used to lower ation in selecting a raspberry site. Gentle pH on alkaline soils, depending on the slopes with outlets for cold air drainage pH and buffering capacity of the soil. significantly reduce frost and freezing Alkaline soils frequently are associated injuries. Low-lying frost pockets that trap with alkaline irrigation water, making pH cold air are poor choices for raspberry management particularly challenging. Soil production. Good air drainage can also acidification is discussed in more detail in reduce excessive humidity in the planting, Chapter 6. an important factor in reducing fungal and bacterial diseases. Other considerations Steep slopes can increase soil ero- Consider previous land use before sion and make operation of tractors and selecting a raspberry planting site. Tree other machinery difficult and dangerous. fruits, strawberries, tomatoes, potatoes, Exposed, windswept sites generally are eggplants, peppers, and caneberries can less suitable for raspberry production than harbor Verticillium wilt, a serious disease more protected locations. in raspberries. A site with a history of serious Phytophthora root rot problems Soils in caneberries is not likely to be a good Suitable raspberry soils are deep and choice. well drained with a sandy to loamy tex- Some soil-applied herbicides can ture. Loam and sandy-loam soils 2 to remain active for many years. Also con- 4 feet deep generally provide the best soil sider surrounding farming activities. conditions, provided they are well drained. Determine whether pesticide spray drift Sandy or gravelly soils can be suitable for from adjacent farms might interfere with raspberry production, as long as adequate production or with organic certification. irrigation water is available. Water and

22 Chapter 4. Plantation Establishment

Site preparation green manure crops are included in Chapter 9, "Organic Production." A green Site preparation is an important step in manure crop may not be needed where developing a successful raspberry farm. raspberries follow hay, legumes, or other Preplant activities often include leveling soil-improving crops. Sites that have been fields; adjusting soil pH; and installing planted to sod should be cultivated or rota- wells, irrigation main lines, and drainage tion cropped for at least 1 year to kill the tiles. grasses and create suitable planting beds. Before planting, identify your soil's Although soil organic matter is impor- characteristics and potential problems. It's tant to soil tilth and fertility, raspberries do best to conduct soil tests at least 1 year not require high concentrations for accept- before planting. Early testing allows for able growth and fruiting. An earlier edition pH adjustment, which is best done before of this guide recommended applying 8 to planting, and for planning fertilization pro- 12 tons of barnyard manure or 5 to 6 tons grams. Some materials, such as lime, are of poultry manure per acre before planting best incorporated before planting. raspberries. While such applications can Typical analyses include pH, organic be beneficial, transporting and applying matter, phosphorus (P), potassium (K), large quantities of manure can be expen- sulfates (SO4), boron (B), and lime sive and may be feasible only if fields are requirement. Soil nitrogen analyses for located near a livestock operation. Use soil nitrate (NO3) or ammonium (NHt) may be tests to determine whether large manure conducted, but are less useful. Tests for applications will be cost-effective. For salinity and other macro- and micronutri- barnyard manure, use only materials that ents are available, if needed. See Chap- have been well composted to reduce the ter 6, "Plant Nutrition Management," for likelihood of importing noxious weeds. more information. Woody materials, including straw, bark, Test raspberry field soils for the kinds and sawdust, sometimes are incorporated and numbers of nematodes (microscopic into the soil before planting fruit crops. worms) present. Some nematodes transmit Soil microorganisms use nitrogen as they serious diseases to raspberries. If plant- break down organic materials. Unless parasitic nematodes are present, fumi- extra nitrogen is applied with uncom- gation or other soil treatments, such as posted, woody amendments, soil nitrogen soil solarization, may be required before can become temporarily depleted, creating planting. For more information on nema- nitrogen deficiencies in crops. todes and plant diseases, see Chapter 7, If hardwood sawdust or bark is incor- "Raspberry Disease and Nematode Man- porated into the soil, apply 25 pounds agement." Note that soil solarization has of actual nitrogen for each ton of woody not proven particularly effective in Idaho's material. For softwood (conifer) or straw cool climate. materials, apply 12 pounds of nitrogen per Depending on the previous cropping ton. The following year, add about half as history, it might be beneficial to produce much nitrogen as the first year, in addi- and incorporate a green manure crop tion to the fertilizer needed for the crop. before planting raspberries. When used As with manures, purchasing, transport- properly, green manures help maintain soil ing, and applying bulky soil amendments organic matter and soil structure (tilth). usually is expensive and may not be cost- Suggestions for selecting and managing effective.

23 Chapter 4. Plantation Establishment

Planting stock are surface-sterilized and placed on a spe- cial growth medium in sealed containers. Use only certified planting stock to The plants are grown in rooms or cham- reduce the likelihood of introducing nema- bers where light and temperature are care- todes, viruses, root rot organisms, and fully controlled. The small shoot sections, other pests into new fields. Using planting called explants, produce many new shoots stock from your own fields or from neigh- that can be rooted in similar containers or bors is not advisable because of the risk of in a soilless growing medium under high introducing pests and diseases. humidity in greenhouses. Although red raspberries are among the Because each explant produces many easiest fruit crops to propagate, very few new shoots, tissue culture allows a nurs- commercial growers produce their own ery to produce large numbers of plants planting stock. Propagating high-quality quickly. More importantly, tissue-cultured planting stock requires significant invest- plants can be, theoretically, free of viruses ments of time, labor, equipment, land, and and other disease organisms. structures. Most growers find it more cost- Unfortunately, newly rooted tissue- effective to purchase raspberry plants from cultured plants are small, tender, and often certified nurseries that have the resources survive poorly if transplanted directly and expertise to produce true-to-name, dis- to fields. Most growers have better suc- ease- and pest-free stock. Several kinds of cess with plants that have been grown for planting stock are available. 1 year in a greenhouse or nursery trans- Dormant plants from the previous plant bed after rooting. season's growth have long been favored Although more expensive than tra- by commercial growers. Canes should ditionally grown nursery stock, tissue- be at least VA inch in diameter with well- cultured planting stock can provide greater formed root systems. Cane length is unim- protection against introducing pests and portant and typically ranges from about diseases into fields. Bear in mind, how- 3 to 12 inches. Use care during digging, ever, that once the tissue-cultured plants storage, transport, and planting to ensure are rooted out in nursery greenhouses or that the hair (feeder) roots are not pulled fields, they may become infected with pest off and that the roots remain moist at all and disease organisms. times. Regardless of the planting materials Alternatively, dormant root cuttings used, ensure that the nursery providing the from certified nurseries can be used as materials is certified by the state agricul- planting stock. Small, white buds on the ture department and has a reputation for root cuttings give rise to new shoots. This selling high-quality, disease-free plants. method increases the amount of planting For all types of planting stock, be careful material available and produces results not to allow the plant materials to dry out similar to those achieved with rooted before, during, or after planting. plants. Root cuttings generally are !/i6 to 3/(i inch in diameter and of varying lengths. In recent years, commercial production Row spacing of raspberry planting stock has improved The distance between rows is an impor- greatly with the development of tissue tant consideration in designing a raspberry culture techniques. In this propagation planting. Spacing the rows too far apart system, small sections of raspberry shoots reduces yields. Spacing the rows too

24 Chapter 4. Plantation Establishment

closely together, on the other hand, makes recommendations on row spacing and maintenance and harvest difficult. Row training systems. spacing is a decision that lasts for the life For mechanically harvested fields, row of the planting. Take the time to make the length is determined by the maximum correct choice before planting. length of drip irrigation tubing (if used) In the early 20th century, raspberry and the capacity of the harvest equipment. rows often were spaced 6 feet apart. This If the crop is to be hand harvested, place close spacing worked well for horse-drawn cross roads no more than 150 to 200 feet equipment, but generally is impractical apart to allow workers to move the fruit to with tractors, mechanical harvesters, and roads for pickup. other modem equipment. Typical spacings today are about 10 to 12 feet apart. Allow Planting systems plenty of room at the ends of rows to turn Because they produce primocanes from equipment around. both the crown area and from buds on Design row spacings based on the the roots, red raspberries can be grown equipment that will be used. If a small in either hedgerows or hill systems. In tractor is used, crop rows are properly mature hedgerows, individual plants narrowed, and canes are supported on trel- are not distinguishable. Instead, there is lises, row spacings of 8 feet are possible. a continuous row of canes (Figure 2B Such narrow spacing is not always conve- and Plate 1). In hill systems, individual nient, however. plants are distinguishable. See Figure 2A, Larger tractors and some over-the-row Figure 3 (page 26), and Plate 2. harvesters require wider row spacing. If In commercial plantings, summer- the field will be mechanically harvested, bearing raspberries can be grown in either consult the equipment manufacturer for system. Hedgerows are common for

Figure 2. Typical four-wire trellis design showing unpruned and pruned winter canes for (A) hill-trained red raspberries and (B) hedgerow-trained red raspberries. The top wires usually are 5 to 6 feet above ground. 25 Chapter 4. Plantation Establishment

summer-bearing raspberries in the eastern density in hedgerows can be managed Pacific Northwest, where most fields are by removing some primocanes during hand harvested. Spacing the floricanes winter or spring pruning, leaving a desired along the row can facilitate hand picking. spacing between adjacent canes. This In western Oregon and Washington, most practice is used only for summer-bearing commercial summer-bearing raspberry raspberries. See Chapter 5, "Plantation growers use hill systems. Maintenance," for more information. Primocane-fruiting red raspberries are While hedgerows have the advantage always grown in hedgerows. of making hand picking easier, they have several disadvantages. Canes in hedge- Hedgerow systems rows are shortened or topped to about Hedgerows are best established by 6 feet high since they are too spread out to planting rooted plants or root cuttings bundle and tie to the trellis wires. Topping about 2 feet apart in rows. Primocane- reduces yields, and the shorter canes can fruiting raspberries typically are grown in slip between the top wires, necessitating 12- to 18-inch-wide hedgerows, whereas tying the canes to the wires and increasing summer-bearing hedgerows are kept about labor costs. Training and trellising are dis- 12 inches wide. The hedgerow width is cussed in Chapters. maintained through hand pruning, mow- ing, chemical cane burning, or rototilling Hill systems along the edges of the rows. Summer-bearing red raspberries can Overly dense canopies increase pest be grown in hill systems on raised beds and disease problems and can reduce or flat ground. The canes are trained by flower bud formation due to shading. Cane tying them together in bundles, which then require some form of support. Canes tied to top wire By bundling canes together and Wiretensioner arcing them over the trellis wires (Figure 3), growers see increased yields over hedgerow systems, where canes must be topped. This factor is especially important in the long, warm growing region west of the Cascades, where canes grow taller than they do east of the Cascades. Hills usually are established by setting traditionally propagated or nursery-matured planting stock 2l/2 feet apart in the rows. Canes traditionally have been thinned to limit the number of canes per hill, Open hook although some recent research chal- Figure 3. Typical three-wire trellis design for arc-trained red raspberries. The lenges that practice. top wire usually is 41/2 to 6 feet above ground. Wire tensioners at the ends of Although home and market gar- rows and open hooks on the poles allow the lower wires to be pulled out to deners sometimes use fence poles to catch canes and bring them into the centers of the rows.

26 Chapter 4. Plantation Establishment

support canes in hill systems, commercial raspberries, two wires are strung tightly growers utilize various trellis designs. together. Primocanes are trained by pinch- ing them between the two wires. While Trellis designs the idea is to eliminate the need for tying, in practice the canes tend to slip from Summer-bearing cultivars between the wires. Commercial summer-bearing red rasp- A more common design is to fasten two berries require trellises for support. Many rather loose wires directly to the posts or trellis configurations have been developed, to short cross arms about 24 inches above and it is beyond the scope of this guide the ground. These wires are pulled out and to describe all of them. If the crop will be down to capture and hold young canes and mechanically harvested, consult the har- then retightened, thereby protecting the vester manufacturer to determine which canes from damage by workers and equip- trellis system is best for your equipment. ment. One or two more wires are placed Between the wire tension and weight 4/4 to 6 feet above ground, and the canes of the canes and fruit, the stress on the are tied to these wires (Figure 3). For arc end posts can be very high. Row ends training, bundles of canes can be bent over often consist of two cross-braced posts the top wires and fastened to another wire set deeply into the ground, often leaning below (Plate 3). backwards from the trellis wire. Fastening The designs discussed so far utilize one each end post to a buried concrete anchor or two top wires, with all canes trained in provides additional support. a single, narrow row. In another design, Wire tension is maintained by using cross arms on the support posts hold two ratcheting tensioners located at the ends of to four top wires 1 to 3 feet apart in what the rows. For very long rows, additional is called a divided or V trellis (Plate 4). tensioners may be required along the rows. Theoretically, dividing the canopy Always treat wooden posts to resist rot increases light exposure and air movement and use rust-proof, high-tensile, 10- to into the canes, thus increasing yield and 12-gauge wire. reducing disease problems. This design The simplest trellis consists of a single can be used with both hedgerow and hill- wire strung about 5 to 6 feet above ground trained plants. and supported on wooden or metal posts While the divided canopy system spaced 25 to 30 feet apart. Two-, three- or has enjoyed some success in the eastern four-wire trellis systems are more common United States, it has not proven as popular in commercial plantings. or economically beneficial in the Pacific In many designs, one wire is run about Northwest. The added cost of constructing 12 to 24 inches above the ground to sup- and maintaining the trellis, plus the extra port the drip irrigation line. Keeping the labor needed to tie up a divided canopy, lines above the ground greatly reduces makes a V trellis impractical for some damage to the irrigation tubing during growers. pruning and other operations. Snap fasten- ers are commercially available to hold the Primocane-fruiting cultivars irrigation tubing to the trellis wire. These cultivars can be grown free Upper wires usually are placed 5 to standing, but often are supported on a sim- 6 feet above the ground. In some designs ple trellis to keep the canes from bowing for hedgerow training of summer-bearing out into the alleys (Figure 4). Because the

27 Chapter 4. Plantation Establishment

18 inches

Figure 4. Typical trellis designs for primocane-fruiting raspberries.

wires in this case bear little weight, end rooted plants, root cuttings, or tissue- and in-row support posts can be lighter cultured plants, keep the shipping and than for summer-bearing raspberries. storage times as short as possible. Run one trellis wire along each side of Most planting stock is shipped while it the berry row about 2 to 3 feet above the is dormant and relatively tolerant of low ground. Anchor the wires to a post at each temperatures. Tissue-cultured plants can end of the row. Every 25 to 30 feet, use be shipped when they are actively grow- a crossbar 12 to 18 inches wide to sup- ing, but they can be damaged by freezing port the wires and keep them from being temperatures. High temperatures can dam- pushed outward. The crossbars can be age any planting stock. made of reinforcing bar used for concrete If possible, keep plant materials refrig- work. Twist the ends of the bar into small erated at 32 to 360F until you are ready to loops and string the wires through the plant. Tissue-cultured plants will not be loops. damaged at these temperatures. While in shipment and storage, the Planting roots must be kept moist. Usually this is Although raspberries are remarkably accomplished by enclosing the roots or tough plants, care is needed during plant- entire plant bundles inside plastic bags and ing to ensure survival and rapid establish- storing them in a refrigerator. Moist excel- ment. Order plants well in advance and sior, shredded newspaper, sphagnum moss, specify the shipping date. Whether using or other materials sometimes are packed around the roots to retain moisture.

28 Chapter 4. Plantation Establishment

When planting, remove from storage Self-propelled or tractor-drawn mechan- only as much stock as can be planted in ical transplanters are available for larger an hour or so. Keep the roots moist during plantings. Depending on the design of the transport to the field and planting. A com- transplanter, long roots can create difficul- mon method is to wrap wet burlap bags ties and may need to be trimmed. Some around the roots. transplanters simply create a planting fur- row. Workers riding on the transplanter set Setting the plants plants by hand into the furrows. Packing Raspberries can be planted by hand, by wheels on the back of the transplanter firm machine, or by a combination of the two. the soil around the raspberry plants. If the plants are to be set by hand, V-shape Planting depth is an important factor furrows generally are used. The furrows in establishing a raspberry plantation. Set can be made with various tractor-drawn tissue-cultured plants just slightly deeper implements, including plows and disks. than the plugs. Canes are best planted at Using a road, fence, or other object as a the depth at which they were growing in guide, create an initial furrow. That furrow the nursery. Plant root cuttings shallowly serves as a guide for subsequent furrows. 3 and cover with approximately /4 inch of Often, a marker stick or similar device soil. is attached to the front of the tractor. By Regardless of the planting method used, keeping the marker over the previous row, always have someone follow the planters the driver can create uniformly spaced to correct any mistakes. Heavily irrigate rows. the raspberry plants as soon as possible to For hedgerows, space plants or cuttings help settle the soil around the roots, elimi- about 24 inches apart. For hill systems, set nate air pockets, and keep the plants from plants about 30 inches apart. Marker sticks drying out. provide a convenient way to ensure con- While the plants are establishing, irri- sistent in-row spacing. gate frequently enough to keep the soil With rooted plants or root cuttings, moist. Irrigation is especially important for spread the roots along the bottom of the tissue-cultured plants and root cuttings. furrow and cover with soil. Unless they Traditionally, authorities have recom- are visibly damaged, raspberry roots are mended cutting the tops of the floricanes seldom pruned during hand planting. (sometimes called the handle) to 3 to Tissue-cultured plants also can be set 4 inches above the ground at the time directly into fields, although they are ten- of planting. Ideally, three to five strong der, and survival can be problematic. primocanes will develop from the plant. These canes will bear fruit the following year.

29 Chapter 4. Plantation Establishment

30 Chapter 5. Plantation Maintenance

Chapter 5

Plantation Maintenance

Row management Removing spent floricanes Regardless of the planting system, use The floricanes of summer-bearing rasp- a mower or cultivator to remove canes berries can be removed any time from just emerging in the alleys or outside the after harvest through the following spring. desired row. For summer-bearing rasp- After harvest, floricane leaves turn yellow berries, keep rows about 12 inches wide. and eventually fall from the dying canes. For primocane-fruiting raspberries, keep Research has shown that nitrogen, carbo- rows 12 to 18 inches wide. When summer- hydrates, and other important plant bio- bearing raspberries are grown in a hill sys- chemicals move from the dying floricanes tem, the primocanes that emerge between into the crown and roots. This recycling of hills are also removed. nutrients and plant compounds provides perennial plants great survival and growth advantages. Movement of these chemicals, Pruning and training however, requires time; thus, most experts Summer-bearing raspberries recommend delaying floricane removal Pruning and training of summer-bearing until late fall. In western Oregon and raspberries includes floricane removal, Washington, the spent floricanes typically primocane pruning, optional primocane are removed just before training the pri- thinning, and primocane top management. mocanes in the fall. These activities usually are done in fall However, if diseases, such as yel- and winter. low rust, are creating serious problems, remove the floricanes as soon as possible after harvest. Some growers also choose to remove spent floricanes immediately after harvest due to labor considerations.

31 Chapter 5. Plantation Maintenance

Pruning primocanes summer-bearing raspberries, although it Primocane productivity depends on reduces yields. Leaving the canes as long cane diameter and internode length. In as can be conveniently harvested generally both the hedgerow and hill systems, prun- increases yields. ing primocanes involves removing canes Topping primocanes before a cold spell that are damaged, very thin (pencil width can increase the risk of cold injury to the or smaller), too short to train, or outside cane wood and buds, particularly in mild the hill or row. Primocane pruning can western Oregon and Washington areas. take place anytime during the dormant Growers commonly top the primocanes season. On colder sites in and east of the after the bundles have been tied to the Cascade Mountains, primocane pruning trellis and the risk of temperatures below often is delayed until late winter or early 50F has passed. Topping usually is done in spring (before growth starts), so that the February in the western Pacific Northwest; grower can identify and remove winter- it may be delayed until March or April on damaged canes. cooler eastern Pacific Northwest sites. In the second method, the primocanes Thinning primocanes are not shortened. Instead, they are bent Some growers also manage cane density over the top trellis wire to form an arc in hills by thinning primocanes. However, in a practice referred to as arc training research has shown that increasing the (Plate 3). In fields that are machine har- number of primocanes per hill increases vested, the canes should be arced in the yields. In an Oregon study, for example, direction of machine travel down the row the greatest yields were obtained with to avoid cane breakage during harvest. 15 canes per hill when compared to 5- or The third technique combines topping 10-cane systems. Similar results have been and arc training. In this method, a small reported in Washington and Idaho, with portion of the primocane tip is removed. densities of up to 20 canes per hill proving The amount removed depends on cane productive. Although the number of canes vigor. The primocanes are then bundled per hill can impact canopy density and, and arc trained. therefore, susceptibility to diseases, can- In Oregon trials, keeping the entire cane opy density can be more easily managed length (averaging about 9 feet) during through training practices (see "Managing training increased yields by 20 to 25 per- primocane tops," below). cent compared with shortening canes For hedgerow-trained summer-bearing to 6 feet. Average berry size, however, red raspberries, thinning the primocanes decreased by about 10 percent. It seems to leave four to six strong canes per lineal that fruiting laterals at the tips of untopped foot of row is a common practice. canes are short and produce relatively small fruit, thereby decreasing the average Managing primocane tops berry weight for the hill. Pacific Northwest growers use three For fresh market production, keeping methods for managing primocane tops. In the entire cane length might be a disadvan- the first method, primocanes are topped to tage because of the potential for reduced 6 feet in length or 6 inches above the top fruit size. Shortening the primocanes pro- wire. Topping was long a standard tech- vides less of a disadvantage for fruit des- nique for hill-trained berries and continues tined for processing markets, where small to be common with hedgerow-trained changes in fruit size are less important.

32 Chapter 5. Plantation Maintenance

Slightly topping the canes before arc train- late winter or early spring (before growth ing reduces yields slightly compared to starts), so that the grower can identify and keeping full-length canes, but has less remove winter-damaged canes. impact on average berry weight. Summer-bearing red raspberry primo- Pruning for one crop per year canes are not shortened during the grow- Prune or mow off all canes to 1 to ing season, as doing so produces weak 2 inches above the soil, ideally some- canes and overly dense canopies. time between December and February. By this time, the maximum amounts of Primocane-fruiting raspberries nutrients, carbohydrates, and other plant Pruning of primocane-fruiting raspber- reserve compounds have been translocated ries involves removing spent canes and from the canes into the roots and crowns. pruning primocanes. These activities usu- Delaying pruning too long, however, can ally are done in fall and winter. weaken the plants because stored reserves Primocane-fruiting raspberries are will move back into the canes and will be sometimes tipped during the summer to lost. delay fruit set for off-season production In this system, the primocanes are not in greenhouses/hoophouses or in mild- thinned within rows to manage cane den- climate areas. Field-grown primocane- sity. Doing so reduces yields. fruiting raspberries generally are not summer tipped in the Pacific Northwest. Disposal of prunings Many authorities recommend remov- Pruning for two crops per year ing prunings from fields and burying or Removing spent canes. After the pri- burning them in order to reduce pest and mocane harvest, remove the spent flori- disease carryover. While cane removal is canes and the spent, fruit-bearing portion suitable for small plantings, it generally is of the primocanes. This upper section not practical for large plantations. Where normally dies after harvest, but removing pruning removal is not practical, place the it helps reduce disease problems and opens prunings in the alleys between the rows the canopy for easier access. Although the and chop them with a flail mower. Leave spent portions of the primocanes can be the residue on the soil surface to decom- removed as late as the following spring, pose or work it into the soil with a disc or late fall through late winter may be the rototiller. best time to remove them. Primocane- fruiting raspberries usually are not thinned Primocane suppression to manage cane numbers, other than keep- Primocane suppression (also called cane ing rows narrowed to about 18 inches. burning, primocane control, or primocane Pruning primocanes. Primocane pro- removal) refers to the practice of removing ductivity depends on cane diameter and the first flushes of new vegetative canes internode length. Pruning primocanes during the spring when they are approxi- involves removing canes that are dam- mately 4 to 10 inches tall. Raspberries are aged, very thin (pencil width or smaller), unique in that, during the period when too short to train, or outside the hill or row. floricanes are developing berries, new Primocane pruning can take place anytime primocanes are emerging from the crown during the dormant season. On colder sites and roots. The two types of canes compete in and east of the Cascade Mountains, for the plant's carbohydrates and nutrients. primocane pruning often is delayed until

33 Chapter 5. Plantation Maintenance

Theoretically, removing the first one or laterals, few researchers have observed the two flushes of primocanes leaves more yield increases reported during the 1970s. carbohydrates and nutrients for use by Why yields have failed to increase floricanes. The result could be greater fruit remains unclear, but the reason may relate set and larger berries. to the wide spectrum of activity of ear- Some research also suggests that the lier cane-suppressant chemicals. Besides shading produced by tall primocanes suppressing the primocanes and lower reduces light penetration into the canopy, vegetation, the most popular cane-burning thereby reducing potential fruit numbers. herbicide used during the 1970s and 1980s This effect is particularly significant on the could be toxic to disease organisms and lower two-thirds of the floricanes. insect pests. Chemicals labeled for primo- Primocane removal can be accom- cane suppression today are effective herbi- plished either by hand or with the use of cides, but have little or no effect on other chemicals. Because hand removal is labor living organisms. intensive and costly, researchers have Although yield increases seldom are studied ways to use herbicides and other associated with primocane suppression, chemicals for primocane removal. Because the practice continues because it facili- most of these chemicals act by desiccating tates machine harvest. Besides removing or "burning back" primocanes and lower short primocanes, herbicides used for cane fruiting laterals on floricanes, the term burning also remove the leaves and lateral "cane burning" was adopted. shoots on the lower 1 to 2 feet of the flori- During the late 1960s and early 1970s, canes. Keeping this portion of the canopy researchers in the Pacific Northwest and clear allows better closure of the catch- Europe confirmed that yields of red rasp- plates on machine harvesters and results berry plants could be enhanced by primo- in less fruit dropping to the ground. Fruit cane suppression. Reported yield increases borne on laterals near the ground rarely is in the Pacific Northwest ranged from 9 to harvested anyway, and it can increase fruit 92 percent when new primocanes were rot within the rest of the canopy. Remov- chemically suppressed one, two, or three ing the lower fruiting laterals also reduces times using an herbicide. Researchers in disease pressure by increasing air move- Scotland saw similar yield responses when ment around the bases of the plants. the first one or two flushes of primocanes Depending on the herbicide used, pri- were removed by hand. mocane suppression also can improve Because of concern that removing pri- weed control within the plant row, thereby mocanes three times each spring might reducing competition from weeds and severely reduce cane production in sub- further improving air movement. Another sequent years, most growers elected to advantage of primocane suppression is remove primocanes only one or two times that primocanes that emerge later in the each spring. season tend to be shorter at harvest time As of 2005, three compounds were reg- than canes that develop in early spring. istered in the Pacific Northwest for primo- Short primocanes are more resilient and cane suppression, although not all of them often suffer less damage from picking were registered for all states. Although machines than do taller primocanes. these compounds generally are effective in Despite the advantages associated with removing primocanes and lower fruiting cane burning, this practice should be used only with plants exhibiting moderate to

34 Chapter 5. Plantation Maintenance

good vigor. A balance between short- and 40 pounds per square inch. Surfactants long-term yields must be maintained. usually are added to the spray mix to Good primocane development and num- increase herbicide effectiveness. One bers are essential for sustained production herbicide application usually is adequate, year after year. For that reason, it is essen- although in cases of exceptional vigor a tial that primocane suppression not reduce second application may be desirable. As the plants' vigor over the long term. with all agricultural chemicals, carefully Research conducted in Scotland showed read and follow label directions regarding a reduction in the vigor of a planting with rates and times of application. no further yield increases after 4 years Remember that primocane-suppressant of removing the first flush of primocanes herbicides are applied in bands along the by hand. This research was conducted rows, rather than being broadcast through- in the 1970s in a vigorous planting of out the plantation. The objective of the the red raspberry variety 'Glen Clova.' herbicide application is to completely kill Although 'Glen Clova' is not considered to the soil surface all primocanes that have to be as vigorous as 'Willamette' and emerged at that time. Primocanes that are other commercial varieties grown in the not completely killed to the ground con- Pacific Northwest at that time, the finding tinue to grow and tend to produce canes emphasizes the importance of maintaining that are brittle, kinked, or multibranched. adequate primocane growth and vigor for Such canes are difficult to train and are sustained productivity over the life of the prone to breakage. planting. In alternate-year cropping systems, The interaction between primocane primocane suppression can be increased vigor and primocane suppression may be during the cropping year to reduce fruit particularly important for raspberry grow- rot and facilitate harvesting. Although the ers in and east of the Cascades. Primocane additional primocane suppression reduces suppression studies have not been reported the size and number of primocanes, the for the eastern portions of the Pacific plants recover satisfactorily during the Northwest. Of particular concern is the noncropping season. fact that raspberry primocanes growing in cool, short-season areas seldom attain the Mulching heights of those in western Oregon and Mulching fruit crops has long been a Washington. Before using primocane sup- popular practice and remains valuable pression on large acreages in the eastern for some crops. Mulch can help maintain Pacific Northwest, conduct small-scale soil moisture, reduce soil temperatures, tests for several years and carefully record and control weeds. Unfortunately, little data on cane vigor and fruit yield and research has been published on the effects quality. of mulching raspberries. Cane-burning herbicides usually are In northern Idaho trials, sawdust mulch applied in banded applications to the bot- for weed control was compared with vari- tom 18 inches of the floricanes when the ous combinations of hand weeding, cover first flush of primocanes is about 4 to crops, and preemergence herbicide to 10 inches tall. The chemicals usually determine the effects on fruit yield and are applied in 50 to 100 gallons of water quality. After 3 years, fruit yields and qual- per broadcast acre at pressures around ity were similar for all treatments.

35 Chapter 5. Plantation Maintenance

Although the sawdust mulch was quite stamens (male parts of the flower) to the effective in controlling annual weeds, pistils (female parts). quackgrass and Canada thistle problems Each raspberry flower contains 100 to became severe by the second year of the 125 pistils, with each pistil represent- trials as weed rhizomes spread through ing one potential drupelet. About 75 to and under the sawdust. When dry, the 85 drupelets must form in order to produce sawdust repelled water and complicated a normal-looking fruit. Insufficient pol- irrigation. Also, raspberry roots grew into lination or fruit set within a flower leads to the mulch, possibly increasing the risk of the development of small, misshapen, and drought and freezing injury to the roots. crumbly fruit. Mulches also provide excellent habitat for Several processes are involved in voles and other rodent pests, increasing developing a mature fruit. The first step the risk of cane girdling. involves pollination —the movement Earlier research in another part of the of pollen from the male anthers to the country did show increased yields in female stigmas. Providing that the pollen summer-bearing red raspberries mulched is viable, the stigma receptive, and the with straw. However, due to high material, two compatible, the pollen grains begin to transport, and application costs, mulching grow long tubes that penetrate down the summer-bearing raspberries for weed con- styles and into the ovules. Again, provided trol in large plantations seems economi- that the pollen and the ovule are compat- cally questionable. ible, the pollen tube can deliver male Research has shown that mulches might genetic material into the ovule in a process play a role in commercial primocane- called fertilization. fruiting raspberry production. In New Research has shown that bees are York trials, researchers found that apply- responsible for 90 to 95 percent of pollina- ing straw mulch to newly planted, tissue- tion in red raspberry. Both native bees and cultured, primocane-fruiting raspberries domestic honey bees are strongly attracted improved plant survival and performance. to raspberry flowers, which produce large One of the authors of that study, however, amounts of nectar. cautions that mulching for weed control Weather plays an important role in pol- after the first year greatly increases the lination. During wet or windy weather and risk of Phytophthora root rot. When using when temperatures are below 50 to 550F, mulches, take care not to keep the soils too bees tend to remain inactive, particularly moist, as wet soils encourage root rot. domestic honey bees. Bumblebees and All things considered, mulching is prob- other native bees are more likely to be ably most valuable for small plantings and active during inclement weather. While might be beneficial for certified organic some efforts have been made to manage production systems. native bees for pollination purposes, there is little published information on manage- Pollination ment techniques, and colony failure rates Commercial red raspberries are self- are reported to be high. fertile. Cross-pollinizing cultivars are not For commercial raspberry production, required, and large blocks containing a authorities recommend placing at least single cultivar are feasible. Raspberries two beehives per acre of planting. Locate require insect transfer of pollen from the the hives so that flight patterns are not

36 Chapter 5. Plantation Maintenance

against prevailing winds. The hives should are beneficial if cover crops are grown in be in the open and not shaded, with the the alleys between rows. openings facing south. Keep pans of fresh On the other hand, sprinklers use large water near the hives, and place sticks volumes of water, much of which is against the sides and bottoms of the pans applied in the alleys. Wet alleys can inter- to enable bees that fall into the water to fere with access, and irrigating the alleys escape. can increase weed problems. Many insecticides are very toxic to bees Wet foliage and fruit also can increase and should not be used during bloom. If an disease problems. Sprinkle irrigate early insecticide application is necessary during in the morning on dry, sunny days, if pos- bloom, select materials that are least toxic sible, to allow the canopy to dry before to bees and apply the pesticides in early nightfall. morning or late evening when bees are Trickle or drip irrigation systems are inactive. For information on insecticides much more efficient than sprinklers at registered for raspberry production, as conserving water and placing the water well as steps that can be taken to protect exactly where it is most needed, so they bees, refer to the most recent edition of are especially valuable where irrigation the Pacific Northwest Insect Management water supplies are limited or expensive. Handbook (see "For More Information," In addition, there is no need for labor page 97), consult pesticide labels, and to move hand lines or other irrigation work closely with your beekeeper. Also equipment. Weed problems in alleys are see How to Reduce Bee Poisoning from reduced, and the alleys remain dry and Pesticides, PNW591. accessible. Foliage and fruit remain dry, reducing disease problems. Because rela- Water management tively little water is applied and water Most commercial raspberry fields in the application is confined to the rows, erosion Pacific Northwest are irrigated. During problems, particularly on steeper fields, most years, irrigation helps produce larger are reduced. fruits, higher yields, and more and larger Washington State University trials canes. The amount of irrigation water comparing drip and overhead irrigation to apply varies dramatically across the systems for winter squash found that water region's soil types and climates. consumption over a 3-year period was 50 percent less with drip than with over- Types of irrigation systems head systems. Drip irrigation produced Both overhead and drip irrigation sys- 50 percent fewer weeds and 75 percent tems are used in commercial raspberry less weed biomass than did overhead irri- production in the Pacific Northwest. The gation. Individual fruit weights averaged type of irrigation system depends on plant- 83 percent greater in year 1 and 19 percent ing size, slope of the land, and the avail- greater in years 2 and 3 under the drip ability and cost of water. Where water is system. abundant and inexpensive, overhead sprin- On the downside, installing the filters, klers often are used. Sprinkler systems main supply lines, lateral drip lines, pres- are relatively simple and inexpensive to sure regulators, and emitters is time- and install, and it is easy to locate malfunction- labor-intensive, and materials are expen- ing sprinklers. Overhead sprinklers also sive. Constant vigilance is required to

37 Chapter 5. Plantation Maintenance

keep filters clear and to locate and repair conductance and dielectric units. Some clogged emitters. Sagging irrigation tub- systems can interface with handheld or ing or trellis wires can create wet spots remote computers for rapid monitoring of around the plant crowns and increase the multiple stations. incidence of root rot. Because drip sys- Tensiometers consist of hollow, water- tems do not water the alleys, establishing filled tubes that have a pressure gauge on and maintaining cover crops, particularly the top and a porous, ceramic tip on the perennial ones, can be more challenging bottom. The tensiometer is buried in the with drip than with overhead systems. soil within the crop row so that only the Many types of drip and sprinkler irri- gauge and top of the tube are exposed. gation systems are available. Properly The gauge registers the difference in water designing an irrigation system requires potential between the soil and the water specialized knowledge and experience. inside the tube. When soils are saturated Hiring a system designer with expertise with water, there is no difference in water in your type of system generally is a wise potential between the soil and the inside of investment. Information on irrigation the tube. As the soil dries, its water poten- system design and operation is also avail- tial decreases and the tensiometer registers able from the University of Idaho, Oregon the difference in water tension. As the soil State University, and Washington State continues to dry, the tensiometer reading University extension services. Online increases. With some experience, a grower and printed catalogs are listed under "For can estimate the amount of irrigation water More Information" (page 97). needed based on the tensiometer reading. Too much water greatly increases root Tensiometers are most effective for mod- rot and physiological problems. Too little erate- to heavy-textured soils. water creates water stresses that limit cane Electrical conductance units have and fruit development. The critical times been used for years and are increasing in for irrigating both summer and fall crops popularity as small, inexpensive, easy-to- are during bloom and as the berries are operate units have become commercially increasing in size prior to the first picking. available. A sensor block, often containing Plantings on medium-heavy soils should gypsum, is buried within the root zone be irrigated heavily just before the first in the crop row. Several blocks often are picking, and may not need additional irri- buried at different depths. Wires extend gation until after harvest. Lighter textured from the block to the soil surface and soils may require an extra irrigation before attach to a portable unit that resembles a harvest and one or two during harvest. volt-ohmmeter. With some grower experi- ence and calibration for soil type, electri- Tools for measuring soil moisture cal conductance units provide rapid, easy Historically, fruit growers judged soil estimations of soil water status and irriga- moisture based on feel and experience. tion needs. Electrical units also lend them- Although examining and feeling the soil selves to computer-assisted monitoring are valuable methods for determining and automated irrigation systems. moisture status, growers now have addi- Dielectric probes estimate soil mois- tional tools to help them make irrigation ture by measuring the dielectric constant decisions. Common tools include evapo- of the soil. The dielectric constant of ration pans, tensiometers, and electrical water is much higher than that of the air

38 Chapter 5. Plantation Maintenance

or mineral components of soil. Some units combine dielectric probes with tempera- Evaporation pan method 1: ture probes (to measure air and soil tem- Scheduling irrigation based on soil type peratures) and rain gauges. Some models Soils vary in the amounts of water they have available for allow the information to be broadcast to plant use. Silt loams contain about 9.6 inches of available handheld or office computers or monitors. water in the top 4 feet of soil. Sandy loams can hold about Evaporation pans are simple, reliable 8.1 inches of available water in the same amount of soil. With devices that help determine the time and this information, one can determine irrigation needs. amount of water to apply. An evapora- In Example 1, the soil has a moisture-holding capacity of tion pan consists of a copper or stainless 2 acre-inches per foot of depth, making a total of 8 inches steel tub approximately 10 inches deep for the 4-foot rooting depth. Allow 65 percent removal of the and 48 inches in diameter. Each day, the water (5.2 inches) before irrigating. Raspberries use 1 inch of grower records the amount of water evap- irrigation water for each inch of water lost from the evapora- orated and a measure of wind during the tion pan. Therefore, 5.2 inches of water must be applied to preceding 24 hours. Experimentation has bring the soil back to saturation or field capacity. helped determine the correlation between The distribution patterns of sprinklers are not uniform; a water needs for particular crops and evap- conservative estimate is 75 percent coverage. Applying this oration pan data. For raspberries, 1 inch of efficiency factor to an irrigation system rated at 0.33 inch water usually is applied for each inch of water per hour shows that 21 hours of irrigation are needed to water lost from the evaporation pan. apply 5.2 inches of water. Not every grower needs to maintain an evaporation pan. In topographically Water use between irrigations uniform areas, one pan per county may be Effective root depth 4 feet sufficient. University research and Exten- Available water per foot sion centers and other units that report of soil depth 2 inches weather data to the National Weather Ser- Total water available (4x2) 8 inches vice often record daily evaporation pan data. Use 65% of water before irrigating (0.65 x 8) 5.2 inches Using evaporation pan measurements Evaporation equivalent You must keep track of rainfall amounts (5.2x1.0) 5.2 inches in order to use evaporation pan data. The Irrigation examples on this page and on page 40 illustrate three ways to use evaporation Sprinkler application rate 0.33 inch per hour pan data to plan irrigation. While these Sprinkler efficiency examples are based on overhead irriga- or coverage 75% tion, they also apply to drip systems. For Length of irrigation needed 5.2-(0.33x0.75) = 21 hours drip systems, estimate the percentage of the field that requires irrigation and reduce the values in the examples accordingly. For example, if raspberry root zones are 3 feet wide and spaced 10 feet apart, only 33 percent of the field requires irriga- tion. Apply one-third the amount of water shown in the examples. Experience with

39 Chapter 5. Plantation Maintenance

your particular irrigation system, soils, Evaporation pan method 2: and field layouts will allow adjustments to Determining length of irrigation ensure desired moisture levels. based on an irrigation schedule Weed management Some growers irrigate on a regular schedule. Evaporation pan Weeds are plants that are naturally data can be used to tell how long to irrigate at each application. invasive, competitive, and persistent. By Time between irrigations 10 days competing for light, water, nutrients, and Evaporation measured space, weeds reduce the vigor of raspberry during the 10-day period 2.56 inches plants and decrease berry quantity and quality. Weeds make harvesting and train- Inches of irrigation water ing more difficult. They harbor raspberry needed (2.56 x 1.0) 2.56 inches pests and diseases, for example by shel- Sprinkler application rate 0.33 inch per hour tering insects from insecticide sprays or Sprinkler efficiency by acting as secondary hosts for disease or coverage 75% pathogens. Length of irrigation needed 2.56 -T- (0.33 x 0.75) = 10.3 hours Most raspberry rows are about 10 feet apart, with VA- to 2!/2-foot-wide weed-free strips on either side of the row centers. The weed-free strips usually are managed with herbicides. In organic production, Evaporation pan method 3: weed-free strips usually are maintained Deciding when to irrigate through hand weeding or the use of a thick with a fixed length of irrigation mulch. Desired length of set 12 hours In order to effectively manage weeds in raspberries, it is essential to identify which Application rate 0.33 inch per hour weeds are present. Different weeds are Amount applied in 12 hours susceptible to different methods of control. (12x0.33) 4 inches Take the time to learn each weed's life Usable application cycle before devising an integrated man- (0.75 x 4) 3 inches agement strategy. Amount of soil moisture Types of weeds loss to allow between irrigations 3 inches Annual weeds Annuals are plants that complete their life cycle within a single growing season. Most weed seeds in the soil are from annu- als. Table 4 lists annual weeds common to the Pacific Northwest. There are two types of weedy annuals. Winter annual weeds usually germi- nate in the fall or early winter and begin actively growing again in late winter or early spring. Many winter annuals flower, produce seed, and die before summer

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officially begins. Summer annual weeds spotty and relatively thin. This allows tend to germinate in the spring, flower in light to reach the soil surface, stimulating summer, and die in the fall. In the Pacific weed seeds to germinate. Similarly, when Northwest, winter annuals are more preva- raspberry canes decline due to diseases, lent in areas with mild winter climates, insects, or poor cultural practices, leaf while summer annuals predominate in canopies become thinner, light penetration regions with colder winter temperatures. increases, and annuals again have opportu- These designations are not hard and nities to invade. fast, however. For example, not all annuals Annual weeds are easiest to control germinating in the fall are winter annuals. when they are young. As an annual weed Some summer annuals begin growth in the grows, it becomes increasingly difficult fall and may not be killed if winter tem- to kill, regardless of the control method peratures are mild. These overwintering employed. In addition, seedling annuals annuals are particularly difficult to control, are much less likely to compete with rasp- given their large root systems and early berry plants than are older annuals. Conse- onset of growth. quently, weed management efforts should Annuals typically are more of a prob- begin as soon as possible after weed seed lem in very young or very old raspberry germination or, in the case of mulching plantings. Before raspberry plants have or preemergence herbicides, before ger- fully established, leaf canopies can be mination. With annuals, it is particularly

Table 4. Common annual weeds in Pacific Northwest red raspberry fields.

Mostly west of the Cascades Mostly east of the Cascades Throughout the region Winter annuals Little bittercress (shotweed) Downy brome (cheatgrass) Henbit Purple deadnettle Field pennycress Common chickweed Shepherd's-purse Ryegrass Annual bluegrass Summer annuals Pale smartweed Green foxtail Pineappleweed Ladysthumb Tumble mustard Redroot pigweed Hedgemustard Kochia Common lambsquarters Pearlwort Mayweed chamomile (dog fennel) Barnyardgrass Hawksbeard Fiddlenecktarweed Wild mustard (several species) Wild radish Russian thistle (tumbleweed) Purslane Catchweed Wild buckwheat Flixweed Prickly lettuce Blue lettuce Annual sowthistle

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important to prevent seed set, as seeds rep- the rosette produces a stalk, flowers, and resent future infestations. seeds, after which the plant dies. Under certain conditions, biennials live more Biennial weeds than 2 years. This might occur when plants Biennial weeds are species that require are mowed prior to flowering the second two growing seasons to produce seed. year or if the second winter is especially Table 5 lists biennial weeds common to mild. the Pacific Northwest. Biennials are best managed during their Biennial weed seeds usually germinate first (vegetative) year of growth, before in the spring, but they may sprout any root carbohydrate reserves build up and time until fall if soil conditions are favor- the plants' ability to resprout increases. able. First-year biennials typically form a Biennial seedlings can be controlled in the rosette—a low-growing tangle of leaves same ways as seedling annuals. that does not produce a true stem. These Like annuals, biennials depend on seed rosettes remain vegetative until they are production for future infestations. Take exposed to cold temperatures (vernal- care not to allow biennials to go to seed. ized) during the winter. Once vernalized,

Table 5. Common biennial weeds in Pacific Northwest red raspberry fields.

Mostly west of the Cascades Mostly east of the Cascades Throughout the region Tansy ragwort Salsify Bull thistle Sweet clover Wild carrot Burdock Common mullein

Table 6. Common perennial weeds in Pacific Northwest red raspberry fields.

Mostly west of the Cascades Mostly east of the Cascades Throughout the region Common catsear Field bindweed Common dandelion Broadleaf dock Chicory Canada thistle Hedge bindweed Smooth brome Curly dock Stinging nettle Red sorrel Tall fescue White clover Velvetgrass Horsetail (Equisetum) Creeping bentgrass Yellow nutsedge Fireweed Quackgrass Blackberry Orchardgrass Creeping buttercup Timothy St. Johnswort Yarrow Common tansy Common mallow Plantain (broadleaf and buckhorn) Reed canarygrass

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Perennial weeds Methods of weed management Perennial weeds are species that live Hand weeding for 3 or more years. Table 6 lists perennial Hand weeding can be very selective and weeds common to the Pacific Northwest. effective when weeds are seedlings, before Some perennials that are not particu- much root growth has occurred. Annuals larly cold hardy often live for only 3 to generally are the easiest type of weed 5 years, or until cold winter temperatures to control by hand, although the crowns kill the plants. Such species are termed of some annual species readily break short-lived perennials. free from the roots, which are relatively Perennial weed seeds usually germinate resistant to hand pulling. Unless used in the spring, but they may sprout any time repeatedly, hand control rarely is effective through fall if soil conditions are favor- against established perennials. Control able. Some first-year perennial plants pro- weeds before they flower, since weeds that duce flowers, but most are only vegetative. have already flowered can mature seed Most perennials produce seeds, but many after they have been uprooted. also form vegetative reproductive struc- tures, such as rhizomes, creeping roots, Cultivation stolons, bulbs, or tubers, that aid in the Most weed seedlings between raspberry spread and persistence of the species. rows, whether annual, biennial, or peren- Perennials generally fall into two cat- nial, can be controlled by cultivation. egories: herbaceous perennials and woody Break weed roots free from the soil so perennials. Herbaceous perennials are that the plants dry out and die. Cultivat- plants whose foliage and stems tend to die ing large weeds, or cultivating during back to the ground every winter before damp conditions or late in the day, usually resprouting in the spring from the roots. results in poor weed control because roots Woody perennials are primarily tree and left in or on the soil tend to reestablish. brush species with woody stem tissues Unless done frequently, cultivation should that survive above ground by forming not be used for vegetatively reproducing relatively heavy bark and dormant winter perennials, such as quackgrass or Canada buds. thistle, as this method cuts up the veg- Perennial weeds are difficult to manage etative structures and often spreads the in perennial crops such as raspberries. If weed infestation. Cultivate carefully and possible, it is always best to control estab- no more than about 2 to 3 inches deep to lished perennial species before establish- avoid damaging raspberry roots. ing the raspberry block. A combination of frequent tillage and application of translo- Mulching catable herbicides during the year prior to Mulching involves covering the soil raspberry establishment usually will con- surface with natural or synthetic materi- trol established perennial weeds. As with als to prevent light from reaching the biennials, perennial weeds are easiest to soil surface, thus reducing or eliminat- kill when they are seedlings. ing seed germination and often killing recently emerged seedlings. Mulching with organic materials rarely controls established perennials or second-year biennials, as they usually contain enough

43 Chapter 5. Plantation Maintenance

stored carbohydrate to allow them to toward control. Application timing and grow through all but the thickest mulch. herbicide rates also are critically important Mulches also provide a good growth to prevent crop injury while achieving medium for weed seeds that move in after effective weed control. Refer to the most the mulch is in place. recent edition of the Pacific Northwest Use caution when mulching, given the Weed Management Handbook for a list of potential for increased incidence of soil herbicides available for use in raspberries. pathogens in moist, cool soils. Mulches also can provide habitat and protection for Mowing rodents, insect pests, and slugs. Mowing is a nonselective method of weed control commonly used in raspberry Weed barriers and fabrics field alleys. Although mowing rarely kills These sheets of natural or synthetic weeds, it reduces their growth and repro- materials are laid down along the crop ductive potential, particularly if the weeds Use herbicides rows before planting. Raspberries are must compete with a cover crop. Mowing safely! transplanted through holes punched along is most effective if repeated during the the centerline of the rows. Because these growing season. • Wear protective products may interfere with primocane Broadleaf weed species are more likely clothing and emergence and cultivation practices, they to be injured by mowing than are grass safety devices as are not widely used in commercial rasp- weeds. Many established perennial spe- recommended berry production. cies are not noticeably injured by mowing on the label. Depending on thickness and perme- because the large amount of carbohydrates Bathe or shower ability, these materials can effectively con- stored in their root system allows them to after each use. trol certain established perennial weeds. quickly resume growth. Mowing generally • Read the herbi- Other perennials, such as quackgrass, have is ineffective at controlling low-growing cide label—even sharp-tipped shoots that penetrate some weeds. if you've used fabrics. Identify weed species before using the herbicide weed barriers. Weedergeese before. Fol- Weeder geese can help control weeds, low closely the Herbicides particularly in small plantings, and they instructions on Herbicides can be selective or non- can be effective in organic production. the label (and selective in terms of the plants they kill. Weeder geese typically are young (at least any other direc- Some selective herbicides, for example, 6 weeks of age). They usually are kept tions you have). kill only grasses, while others kill only within portable electric fences. Move • Be cautious broadleaf plants. Nonselective herbicides, enclosures frequently enough to result in when you apply such as glyphosate, kill both broadleaves full grazing of weeds, but before raspberry herbicides. and grasses. Herbicides currently available plants are damaged significantly. Weeder Know your legal for use in raspberry rows provide good to geese seem to prefer young grass shoots to responsibility excellent control of seedling weeds, but broadleaf weeds. Geese can be noisy, and as a pesticide few products adequately control estab- they might require protection against pred- applicator. You lished perennial and second-year biennial ators and supplemental feed to keep them may be liable for in-row weeds. healthy. At the end of the growing season, injury or damage Always select herbicides based on the the geese usually are sold for human con- resulting from weed species present. Correct identifica- sumption, and new, young geese are pur- herbicide use. tion of weeds is an important first step chased the following spring.

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Cover crops and • Operating equipment on bare alleys when the ground is muddy can be alley management difficult. The area between weed-free crop rows • Exposed soil can become dry and dusty. is known as the alleyway. Many options Dust on raspberry leaves reduces light are available for managing the alleyways penetration for photosynthesis and in a raspberry planting. One option is to increases the risk of spider mite dam- keep them free of vegetation using pre- age. Dust on fruit lowers its market and postemergence herbicides or repeated quality. cultivation. This strategy has several dis- advantages, however. For these reasons, the popularity of • Bare alleys increase the risk of soil loss vegetation-free alleys for commercial rasp- through erosion and make the soil more berry production has declined. susceptible to compaction from tractors Cover crops are another option for and mechanical harvesters. alleyway management. Grass or broad- leaf crops in the alleys reduce weed seed • Frequent cultivation increases labor, germination and can capture soil nutrients fuel, and machine costs. that might otherwise be lost to runoff or

Table 7. Common cover crops and their characteristics.

Seeding rate Annual nitrogen requirement Common name (lb/acre) Establishment rate (lb/acre) Annual cover crops Barley (spring) 120 fast 30-50 Barley (winter) 120 medium-fast 30-50 Buckwheat (common) 35-60 medium-fast 10-20 Buckwheat (tartary) 25 medium-fast 10-20 Oats (spring or winter) 120 medium-fast 30-50 Peas (winter or spring) 120 medium-fast by soil test Ryegrass (annual) 30 fast 30-50 Wheat (spring) 120 medium-fast 20-50 Wheat (winter) 120 medium 30-50 Grain/Pea 80/100 fast 20-30 Perennial cover crops Fescue (hard) 20 slow 20 Fescue (sheep) 20 very slow 20 Fescue (tall) 25 medium 20 Perennial rye 25 fast 30 Russian wildrye 30 slow 20 Siberian crested wheatgrass 35 medium 20 Standard crested wheatgrass 25 medium 20 White clover 4 medium 0 Red clover 5 medium 0 Yellow sweet clover1 5 medium 0 Strawberry clover 4 medium 0 Birdsfoot trefoil 3 slow-medium 0 1Caution: Yellow sweet clover contains coumarins, which can be fatal to livestock foraging on pure stands.

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leaching out of the root zone. These covers within the alleys. Note that cover crops help maintain soil organic matter content, can become infested with perennial weeds reduce soil compaction, and increase cover through seeds or the spread of vegetative for predatory insects and ground-dwelling reproductive structures. spiders. The timing of cover crop establishment A cover crop may consist of one spe- influences how effectively the cover will cies, such as oats, or multiple species, control weeds. Because climate zones vary such as an oat and vetch mix. Grasses do greatly across the Pacific Northwest, con- not serve as hosts for several important sult your seed supplier or local Extension diseases affecting raspberries and usually office for recommended sowing times in are the major components in cover crop your area. Delaying cover crop establish- mixes. Table 7 lists suggested cover crops, ment until the second or third year after their seeding rates, and establishment planting raspberries helps prevent exces- characteristics. sive competition with the young raspberry Table 8 shows the effectiveness of cover plants. crops in suppressing some common Pacific Cover crop plants may be perenni- Northwest weeds. Regardless of the type als, which survive for several to many of cover crop selected, the stand must years, or annuals, which require reseeding be dense enough to effectively exclude every year. Each type has advantages and weeds and prevent weed seed germination disadvantages.

Table 8. Weed suppression ratings for selected cover crops in western Oregon-grown red raspberries.1

Mid-Mayweeds Mid-June weeds Annual bluegrass Annual bluegrass Chickweed Chickweed Mouse ear chickweed Smartweed, pineapple weed Groundsel Wild radish Cover crop: Shepherd's purse Wild lettuce 'Amity' oat Good Good-excellent 'Flora' triticale Good-excellent Excellent 'Stephens' wheat Good-excellent Good 'Wheeler' rye Excellent Excellent Oat-pea mix Fair-excellent Good-excellent Austrian pea3 Fair-good Good-excellent Vetch3 Poor-fair Fair-excellent Native vegetation control Few weeds present Weeds well established Clean control Excellent = 85-95% suppression; Good = 75-84% suppression; Fair = 65-74% suppression; Poor = below 64% suppression. Varieties change as new selections are named and released by breeders. Also, varieties suited to one area do not necessarily perform well in other locations. Extension agents/educators and seed suppliers can assist in selecting varieties. 3Weed suppression in vetch and pea was directly related to stand quality. Where stands were thick, weeds were effectively suppressed. Stands, however, generally were patchy. Source: Cover Crops for Weed Suppression and Biomass Production in Red Raspberries. D. Kaufman, R. Karow, R. William, and B. Strik. Oregon State University (final report).

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Perennial cover crops nitrogen, making it available to raspberry The main advantage of a perennial plants. The opportunity to use naturally cover crop is that it does not need to be occurring nitrogen in raspberry production reseeded every year. Permanent covers appeals particularly to organic growers, provide clean, attractive alleys that are who cannot apply conventional chemical comfortable for foot traffic. These advan- nitrogen fertilizers. tages are especially important for U-pick Clovers also have disadvantages, of operations. course. Although clover growth can be A dense stand of a low-maintenance lush in spring and fall, the plants can die grass, such as 'Companion' (a mixture back during winter, exposing the soil to of fine fescue and perennial ryegrass) weed establishment or soil loss through helps suppress weeds and provides a good erosion, and leaving the soil surface too year-round surface for heavy equipment muddy for field equipment. Pure stands and foot traffic. Shorter, slower growing of clover also are less resistant to equip- grasses, such as hard or sheep fescues, ment and foot traffic than grasses. Clover minimize the amount of mowing required. growth can be so lush and aggressive in A perennial grass cover crop often is spring that it is difficult to keep the clover called a permanent sod, although the word from invading the berry rows. As with per- "permanent" can be misleading. Unless manent grass cover crops, perennial clo- the grass is properly cared for, it generally vers interfere with subsoiling and raised will thin with time and become weedy, bed maintenance. Clovers can harbor some requiring removal and replanting every viruses that infect raspberries. few years. Clover seeds can survive in the soil The term "sod" also can be mislead- for several years, creating the risk of the ing. Some grasses, such as sheep and hard clover becoming a difficult-to-eradicate fescues, form bunches rather than a dense, weed. Clover seeds are particularly attrac- intertwined turf or sod. Where frost heav- tive to voles and other rodent pests. For ing occurs, bunch grasses suffer much these reasons, some growers prefer not to more damage than do rhizomatous grasses. allow legumes to produce seed. Perennial grass cover crops do have dis- To offset some of the disadvantages advantages. They interfere with subsoiling of both grasses and clovers, clover-grass in alleyways and with throwing soil from mixes sometimes are used. the alleys into the berry rows to maintain Annual cover crops raised beds. Thus, permanent sod cover Late summer- or fall-planted annual crops can be impractical for growers farm- cover crops provide the benefits of ground ing on heavy-textured soils who prefer to cover while allowing subsoiling and other subsoil each year. Unless grasses are kept soil management practices. You can till short by mowing, they can provide habitat the cover crop into the soil in the spring or and protection for mice and other rodent mow and maintain it as weed-suppressant pests. Grass-specific herbicides may be stubble through harvest. needed to keep the cover crop from invad- Cereal grains, most commonly oats, ing the plant rows. wheat, barley, or cereal rye, often are Perennial legumes, such as white clo- used in annual cover crop systems. Winter ver, also can serve as permanent ground grains usually are preferred over spring covers. Legumes can fix atmospheric

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varieties. You can mix cereal grains with this system, volunteer weeds are allowed winter-hardy legumes, such as Austrian to grow and provide ground cover. The pea or vetch, to help meet the grain's weeds typically are managed by mowing nitrogen needs. Remember to treat the or cultivation to minimize or prevent seed legume seeds with a Rhizobium inoculant formation or weed spread into the plant before sowing. rows. Depending on the region, sow grains Managing volunteer vegetation as a between early August and mid-September. cover crop often is frustrating and unsuc- Western Oregon and Washington growers cessful. Managing several weed species sow later than those east of the Cascades. at the same time can be especially chal- lenging. Cultivation might encourage the Native vegetation as a cover crop spread of certain aggressive and highly Managing native vegetation as a cover competitive weeds, such as quackgrass crop appeals to some growers because and Canada thistle. Some weeds also har- it reduces off-farm inputs and requires bor or attract pests, such as plant patho- minimal cost, planning, and effort. In genic nematodes, diseases, or rodents.

48 Chapter 6. Plant Nutrition Management

Chapter 6

Plant Nutrition Management

This chapter addresses nutrient assess- Fertilization is not a substitute for poorly ments and applications for red raspberry timed irrigation, late harvest, or failure production in the Pacific Northwest. to control insects, diseases, rodents, or Fertilizer recommendations are based on weeds. Soil properties such as low pH spacing raspberries 21/2 feet apart in rows and/or poor drainage can limit berry yield. 10 feet apart. Increasing fertilizer rates or adding nutri- Red raspberry plants require chemi- ents already in adequate supply will not cal elements from air, water, and soil to correct these limiting factors. Fertilizer produce vegetative growth and fruit. Low applications should be part of a complete levels of nutrients in the plant can affect management package. growth and yield. Very low nutrient sup- Growers, with the assistance of local plies can lead to physiological disorders, Extension agents and field representa- characterized by leaf discoloration, leaf tives, should consider the nutrient needs of distortion, and other visible symptoms. each field. Soil and tissue sample analyses Mineral nutrients, such as nitrogen, help in determining appropriate nutrient phosphorus, and potassium, are added applications. Recording weather, disease through fertilizers to supplement soil sup- problems, and nutrient application rates plies. Nutrient applications influence yield, and timing will help in interpreting soil fruit quality, and fruit maturity, and they and tissue analysis data. Observations of provide for sustained plant vigor. annual growth (cane number, diameter, In order to gain benefits from fertiliza- and height, and fruiting lateral length), tion, crop management—from selecting yield, leaf color, and fruit quality (amount certified plants to postharvest irriga- of rot and drupelet set) also help in deter- tion—must be appropriate and timely. mining nutrient needs.

49 Chapter 6. Plant Nutrition Management

The goal of fertilizing any high-value Changes in tissue nutrient concentra- crop is to supply the crop with ample tions may not be observed in perennial nutrition in advance of demand, thereby crops, such as red raspberries, for 1 to removing nutrient limitations to yield and 2 years after fertilization. Delays in plant quality. Important considerations include uptake are common, particularly when the economic return from the fertilizer relatively immobile materials, such as investment, environmental stewardship, phosphorus, potassium, and lime, are top- and government regulations. A fertilizer dressed. (Nitrogen deficiency symptoms, application should produce measurable shown in Plate 5, can be corrected more changes in plant growth or nutrient status, rapidly.) Thus, tissue testing in producing or otherwise benefit the crop in a measur- raspberries is best used for end-of-season able way. The increased fruit yield or qual- evaluation of a fertilizer program for the ity produces a return on the investment. next year. If problems such as poor cane growth Tissue testing or foliar discoloration appear during the Plant tissue analyses indicate which ele- growing season, a comparative tissue test ments the tissues contain in adequate, defi- can be used to check for possible nutrient cient, or excessive amounts. Routine tissue deficiencies. Tissue testing to diagnose analysis can help in detecting low nutrient deficiencies may be done at any time dur- concentrations before visible symptoms ing the season. However, when outside the or yield reduction occur. By analyzing normal late-July to early-August sampling dried plant tissues for their nutrient con- period (see "When to sample," below), tent, growers can evaluate the adequacy of also collect a sample from an unaffected some mineral nutrients. This information area for comparison. will help in deciding whether fertilizers Before using tissue testing to predict are needed and, if so, how much and what or evaluate fertilizer needs, the following kind to use. Tissue testing can be used for: information is needed: • Predicting fertilizer needs of annual • When to sample crops • How to sample (plant part, number of • Diagnosing problems leaves) • Evaluating a fertilizer program for • Normal or sufficient concentration perennial crops range for each nutrient Tissue testing can be used to moni- These topics are discussed below. tor and adjust fertilizer use during early When to sample growth stages of annual crops such as Collect tissue samples when nutrient potatoes, sugar beets, or lettuce. By using concentrations are stable. Samples col- a tissue test, growers can anticipate fer- lected just a few days apart during periods tilizer needs for these annual crops. In of rapidly changing nutrient concentra- contrast, using tissue test results to antici- tions can give quite different results. pate current-season fertilizer needs does Changes in nitrogen, phosphorus, and not work well for perennial crops such as potassium concentrations in leaves of raspberries. In part, this is due to the mini- 'Meeker' red raspberry during the grow- mal short-term effects of fertilizer on yield ing season are illustrated in Figure 5. Note in perennial crops.

50 Chapter 6. Plant Nutrition Management that tissue concentrations of nitrogen and How to sample potassium change substantially during Collect samples in paper bags. Collect the season but stabilize in late July and 50 of the most recent, fully expanded pri- early August. Samples collected at this mocane leaves about 12 inches below the time should produce consistent analytical cane tips. Collect only one leaf per primo- results. cane. A single sample should not represent Figure 5 illustrates the danger in col- more than 5 acres nor contain leaves from lecting samples in late September. Foliar more than 50 primocanes. Collect leaves nitrogen concentrations decrease as plants that are free of disease or other damage enter dormancy, so these samples may not if possible. Pick leaves so that the petiole give an accurate picture of the situation (stem) remains with the leaf. Note: Do during the preceding or following growing not mix cultivars in a tissue sample. Each season. sample should represent a single cultivar. For best results, collect raspberry tis- Preparing and shipping samples. Do sue test samples during the stable period not wash the leaf samples. Air dry samples from late July to early August. Sampling if you cannot ship them immediately. Ship raspberry tissue at any other time is not fresh samples early in the week to ensure recommended except when samples are delivery before the weekend and reduce collected for comparative tissue testing.

o iro -»—<<= oOJ c: o o

5/15 6/15 7/15 8/15 9/15 10/15 Date Figure 5. Seasonal changes in nitrogen (N), phosphorus (P), and potassium (K) concentrations in raspberry leaves. Data were collected from Oregon-grown 'Meeker' raspberries.

51 Chapter 6. Plant Nutrition Management

the likelihood of spoilage. Ship samples in 9 feet high and Vi inch in diameter are paper bags. Do not use plastic bags or con- desirable. Canes on primocane-fruiting tainers, as the plant materials may mold or cultivars grow 4 to 6 feet tall. Primocane spoil if placed in plastic. heights are often slightly less in cooler, A list of laboratories that perform tis- short-season locations. sue analyses is available in Laboratories • Low tissue analyses and abundant Serving Oregon: Soil, Water, Plant Tissue, cane growth. Excessive cane growth and Feed Analysis, EM 8677. (Labora- usually is caused by an overabundance tories serving Idaho and Washington are of nitrogen. Lower-than-normal tissue included.) Ordering instructions are found nutrient concentrations are common in "For More Information" (page 97). with excessive cane growth. In this In Idaho and Washington, contact your situation, low tissue nutrient concentra- county Extension agent/educator to iden- tions occur because the nutrient content tify additional analytical laboratories. of the tissue is diluted by the intensive Frequency of sampling growth. This condition should correct Annual sampling of all fields is ideal itself when growth returns to normal. for gathering nutrient status information. Therefore, do not apply extra fertilizer, Annual sampling, however, is not always especially nitrogen, to correct low tissue necessary or financially feasible. Regard- concentrations in a situation of exces- less of whether you collect samples every sive cane growth. Below-normal nitro- year, develop a plan for regular sampling. gen and high vigor also can occur on Begin with fields that are not growing canes with little or no crop. or yielding as desired. Collect samples • Low tissue analyses and weak cane annually from these fields until the prob- growth. If canes are weak, discolored, lem is identified and/or corrected. Divide or stunted, apply fertilizer at rates rec- the remaining acreage into two or three ommended by your local Extension blocks. Sample from one block of fields office. each year. This method allows sampling of • Normal tissue analyses and cane one-half or one-third of the acreage each growth. If tissue analyses and growth year. are within the normal range, continue with the current fertilizer program. Interpreting laboratory results Compare the results from a labora- • Above-normal tissue analyses and tory analysis to the values described in weak cane growth. If the canes are Tables 10-12 (pages 56-58) to determine weak, discolored, or stunted, and tis- whether the crop is receiving adequate sue analyses are above normal, look nutrition. Review cane growth and yields for stress from pests, poor drainage, from the previous growing season. Choose drought, frost, or other factors. the combination of tissue analyses and • Above-normal tissue analyses and crop growth listed below that corresponds cane growth. If tissue analyses are to your situation. Follow the instruc- above normal and cane growth is tions given to manage your fertilization adequate or above normal, reduce the program. amount of fertilizer applied, especially For summer-bearing red raspberries in nitrogen. the western Pacific Northwest, canes 7 to

52 Chapter 6. Plant Nutrition Management

Other considerations slowly downward. This immobility can Tissue analysis results outside the nor- result in soils with decreasing phosphorus mal range cannot always be attributed to a and potassium concentrations as depth fertilizer program. Deficient mineral nutri- increases. ent concentrations in tissues can be caused Additional information about soil by saturated or dry soils; high tempera- sampling is available in Soil Sampling tures; frost; shade; weed, insect, or disease for Home Gardens and Small Acreages, pressure; or herbicide injury. EC 628, and Monitoring Soil Nutrients Several fungicides contain plant nutri- Using a Management Unit Approach, ents. Because tissue samples are not PNW 570-E. These publications are avail- washed before analysis, high copper (Cu), able through Oregon State University. See manganese (Mn), or zinc (Zn) may be the "For More Information" (page 97). result of fungicide residue. High boron (B) and Zn also may occur if liquid or foliar Nitrogen (N) fertilizer was used. Nitrogen requirements vary with yield, cane growth, plant age, soil type, irriga- Soil sampling tion, rainfall, and cultivar. Cane growth is In contrast to the use of annual tissue an initial indicator of nitrogen sufficiency. analyses to manage nutrient needs in rasp- Some raspberry cultivars are more vigor- berry production, soil analyses are most ous than others and may require less nitro- useful when obtained before planting. gen to give the desired amount of cane Collect soil samples during the summer or growth. Less nitrogen is also required in fall before planting to estimate amounts the planting year than in subsequent years. of nutrients, lime, and/or sulfur needed. Excess nitrogen adversely affects yield, After planting, periodic soil analyses can fruit quality, and the fruit's ability to be helpful in diagnosing problems, such withstand shipping. It also can promote as low or high soil pH or the presence of vigorous vegetative growth. Excessive excessive salts. vegetative growth leads to longer, thinner Fertilizers are commonly applied in primocanes with longer-than-normal inter- wide bands centered on the raspberry nodes (distance between buds), thereby rows. While this strategy works well from reducing yield per cane. Excess nitrogen a crop production standpoint, banded also can increase lateral lengths on flori- applications concentrate nutrients and can canes. Long laterals increase the risk of complicate soil sampling. The fact that breakage during machine harvest as well nutrient concentrations vary horizontally as the risk of postharvest fruit diseases. between the alleys and crop rows when Nitrogen fertilization should be based fertilizers are banded is relatively easy on tissue nitrogen concentration, cane to understand. Less obvious is vertical vigor, yield, and irrigation practices. Tis- stratification of nutrient concentrations. sue nitrogen concentration from a late- Phosphorus and potassium are relatively July or early-August sampling should be immobile in the soil and tend to remain between 2.3 and 3.0 percent. where they are placed or to migrate

53 Chapter 6. Plant Nutrition Management

Nitrogen for summer-bearing Apply 25 to 40 lb N/acre about 1 week red raspberries before primocane emergence and an addi- A general guide for nitrogen fertilizer tional 25 to 40 lb N/acre about 1 month needs for summer-bearing red raspberries before the first summer harvest. Apply the is 30 to 50 lb N/acre in the establishment remaining 20 lb N/acre when the primo- year and 50 to 80 lb N/acre in subsequent cane blossoms appear. years. How to apply Fruit firmness may be reduced if excess Nitrogen can be efficiently applied nitrogen is applied from late winter with phosphorus and potassium. Apply through early spring, as a considerable fertilizer in bands about 2 feet wide and portion of early-season nitrogen fertil- centered on the rows. Nitrogen can be lost izer goes to the fruit. In summer-bearing from surface-banded applications if the red raspberries, fertilizer nitrogen that fertilizer is not washed into the soil by rain is applied early (before new primocane or irrigation within a few days following emergence or when primocanes are less application. than 6 inches tall) is taken up by the new primocanes and the fruiting laterals and Nitrogen fertilizer materials fruit on the floricanes. Red raspberries use the nitrate In contrast, when nitrogen is applied (NOs) form of nitrogen more readily than + later (when green fruit is present, approxi- the ammonium (NH4 ) form. Nitrate nitro- mately 1 month before the first harvest), gen is soluble in water and moves into the most of the fertilizer nitrogen is taken up soil or plant rapidly, but it also leaches by the primocanes and little goes to the easily from soil. Ammonium nitrogen is fruit. This nitrogen will be stored in pri- less easily leached because it binds to soil mocanes, crowns, and roots, and is impor- particles. Because nitrate nitrogen gener- tant for sustaining yields from year to year. ally is more expensive than ammonium Summer-bearing red raspberries have been forms, many growers apply urea or other shown to use about 40 percent of their ammoniacal sources of nitrogen. stored nitrogen each year. Ammonium nitrogen is converted into Research has suggested that a split the nitrate form through a process called application of nitrogen fertilizer is best nitrification. Soil pH is one factor control- for maintaining current-season yields and ling nitrification. Ammoniacal nitrogen is acceptable primocane growth for next sea- rapidly converted to nitrate in warm, moist son's crop. Apply one-half of the nitrogen soil with a pH above 6.0. fertilizer about 1 week before primocane Different fertilizer materials are nitri- emergence and one-half about 1 month fied at different rates, especially at lower before the first harvest. soil pH. For example, urea and ammonium nitrate act similarly when the soil pH is Nitrogen for primocane-fruiting 6.0 but differently at pH 5.5. Figure 6 red raspberries illustrates relative nitrification of ammo- Primocane-fruiting red raspberries nium nitrate, ammonium sulfate, and urea. generally require 30 to 50 lb N/acre in Note that all nitrogen sources nitrify faster the establishment year. In subsequent at pH 6.0 than 5.5. years, apply a total of 70 to 100 lb N/acre.

54 Chapter 6. Plant Nutrition Management

D Ammonium nitrate

Ammonium sulfate

Urea

Soil pH

Figure 6. Relative nitrification of nitrogen fertilizers at two levels of soil pH. Results from application of 140 lb N/acre on a western Oregon farm on March 7, with sampling on April 23.

Table 9. Effects of nitrogen application rates on soil pH, SMP1 values, and liming rates.

Dayton silt loam Concord silt loam Bashaw silty clay loam Amity silt loam

Nrate Soil SMP Lime Soil SMP Lime Soil SMP Lime Soil SMP Lime (lb/a) pH pH (ton/a)3 pH pH (ton/a)3 PH pH (ton/a)3 pH pH (ton/a)3

0 5.9 6.6 0 6.2 6.7 0 5.4 5.3 4.34 6.05 7.1 6.9 0 135 5.5 6.5 1 5.8 6.4 1.1 4.9 5.2 4.7 6.4 6.6 6.7 0 270 5.2 6.2 2 5.6 6.3 1.5 4.8 5.1 5.0 6.9 6.0 6.5 1 1Shoemaker, McClean, and Pratt (SMP) buffer lime requirement soil assay. 2Data were collected in Oregon's southern Willamette Valley. 3Liming rates vary according to soil conditions and cultural practices. Consult a soil analytical laboratory to determine appropriate liming rates for your fields. "Lime to pH 5.6. 5LimetopH6.0.

55 Chapter 6. Plant Nutrition Management

Effects of nitrogen fertilizer partially offsets acidification produced by on soil pH subsequent reactions. Use of common nitrogen fertiliz- Of the commonly available nitrogen ers increases soil acidity and the need sources, ammonium sulfate is the most for lime. Table 9 shows the effects of acidifying. Ammonium sulfate can be use- increasing nitrogen rates on soil pH in ful in reducing soil pH on sites with mildly four southern Willamette Valley, Oregon alkaline soils. soils. Urea or other ammoniacal nitrogen Foliar fertilization sources acidify the top 3 inches of soil While foliar sprays have proven effec- approximately 0.1 pH unit for each 100 lb tive for applying zinc, boron, and other N/acre. For example, if nitrogen is applied micronutrients, foliar applications have at the rate of 140 lb/acre, the soil pH will not proven very effective for meeting rasp- decrease by approximately 0.14 pH unit. If berry nitrogen needs. Broadcast granular 140 lb N/acre is used for 3 years, soil pH applications or liquid applications through will decline approximately 0.4 pH unit. drip irrigation systems are recommended Therefore, applying excessive nitro- for fertilizing red raspberries. gen fertilizers has a double cost. The first cost, the fertilizer itself, is not offset by increased yields or economic returns. Sec- Phosphorus (P) ond, the additional nitrogen acidifies the Most soils in Oregon's Willamette Val- soil, which then requires additional lime ley contain adequate available phosphorus to raise the soil pH. Applying 50 lb N/acre for red raspberry production. The same is above a crop's need will require an addi- true for many northwestern soils. tional 0.3 to 0.6 ton lime/acre in 3 years. On acidic, volcanic ash-influenced soils Urea is the most common solid or dry in the Cascade Mountains and in northern nitrogen source. It is less acidifying than Idaho, available phosphorus concentra- ammonium sulfate because the nitrogen tions can be limiting for some crops. in urea undergoes a different process to However, there is no definitive research become available to plants. As urea ini- showing yield or growth responses from tially reacts with enzymes in the soil, the phosphorus applications to red raspberry. soil pH rises slightly. This slight rise in pH Trial applications can help determine phosphorus needs for individual fields

Table 10. Phosphorus recommendations for red raspberries.

If P soil test value is1 Bray extractant Olsen extractant If tissue P is2 Apply this amount of P2O5 (ppm) (ppm) (%) (lb/acre) 0-20 0-10 Below 0.16 60-80 20-40 10-20 0.16-0.18 0-60 Over 40 Over 20 Over 0.18 0 1Use soil tests only for preplant applications. Use the Bray soil test west of the Cascade Mountains and the Olsen or bicarbonate test east of the Cascades. 2Late-July to early-August tissue tests (for established crops).

56 Chapter 6. Plant Nutrition Management

when tissue phosphorus concentrations are is attributed to adequate tissue potassium below normal. Use Table 10 for guidance. levels. While the importance of potassium Tissue testing for 3 to 5 years may be nec- nutrition in plant cold hardiness often is essary before differences are observed. cited, no documentation exists to support Surface applications of phosphorus the idea that higher than adequate tissue are less effective than subsurface band- potassium concentrations increase cold ing due to lack of mobility in soil. Rates hardiness. in Table 10 are for subsurface bands. For Use soil tests to determine preplant the fastest and most efficient movement of potassium fertilization. Tissue analysis is phosphorus to raspberry roots, place bands the best indicator of potassium needs after adjacent to hills on each side of the row crop establishment. Generally, little or no and 4 to 6 inches deep. Double or triple correlation exists between soil and tissue the phosphorus rates in Table 10 for a pre- potassium levels. High surface soil potas- plan!, broadcast, incorporated application. sium and low tissue potassium may indi- Rock phosphate can be used by grow- cate a gravelly subsoil low in potassium, ers practicing organic production. Not all inadequate irrigation, diseases, or other rock phosphates react or release phospho- production problems. rus at the same rate. Finely ground rock In new plantings, one-half to two-thirds phosphate mined in North Carolina, when of the potassium requirement can be applied to a phosphorus-deficient soil at broadcast and incorporated before plant- double the rate of super phosphates, pro- ing. The remaining one-half to one-third duced wheat yields comparable to those can be banded with nitrogen and phos- produced by super phosphate. Rock phos- phorus after planting. No more than 40 to phate material has approximately 30 per- 60 lb K20/acre should be included in cent P205, with a citric acid solubility N-P-K mixtures banded after planting. above 50 percent. Excessive amounts of banded potassium can cause burning of new roots, particu- Potassium (K) larly in sandy soils. Potassium is essential for red rasp- In fields 2 years old or older, potassium berry production; however, the amount of can be banded or broadcast, alone or in potassium fertilizer required is not well combination with nitrogen, phosphorus, defined. Good fruit firmness sometimes and possibly other fertilizers. Use Table 11 to determine potassium fertilizer rates.

Table 11. Potassium recommendations for red raspberries.

If soil K test value is1 If tissue K is2 Apply this amount of potash (K2O) (ppm) (%) (lb/acre) Below 150 Below 1.0 60-100 150-350 1.00-1.25 40-60 Over 350 Over 2.0 0 'Preplan! ammonium acetate soil test. 2Late-July to early-August tissue test (for established crop).

57 Chapter 6. Plant Nutrition Management

Sulfur (S) When sulfur applications are needed, 30 to 40 lb actual sulfur/acre is adequate. Sulfur deficiencies in raspberry crops Gypsum is a common source of sulfur and are not common in much of the Pacific has little impact on soil pH. When soil pH Northwest. Sulfur deficiencies have been values are higher than desired and sulfur reported in some areas, however, most is needed, elemental sulfur can be used to notably on sandy soils in Washington's lower soil pH while providing the needed Skagit Valley. sulfur. Soil sulfur concentrations usually are adequate in raspberry fields because sulfur often is added with other nutrients in fer- Micronutrients tilizers. Fertilizer materials such as ammo- Boron (B) nium sulfate (21-0-0), potassium sulfate Small amounts of boron are critical for (0-0-50), and gypsum contain sulfur. bud break and fruit set of red raspberries. For plantation establishment, apply Boron deficiency results in small fruit, 30 lb actual sulfur/acre if the preplant soil decreased yields, and, in severe situations, test is below 10 ppm. No sulfur should be cane dieback. Table 12 provides boron fer- needed if the soil test is above 10 ppm, tilizer recommendations based on soil or assuming that pH is between about 5.6 and tissue tests. Note, however, that soil tests 7.0. are less effective than tissue tests at pre- Like nitrogen, sulfur is a key compo- dicting boron needs for fruit crops. nent of proteins. Tissue sulfur concen- Boron applications without soil or tissue trations between 0.11 and 0.2 percent tests are not recommended because boron generally are adequate. The ratio of total is toxic to plants at very low concentra- nitrogen to total sulfur in tissue typically tions. In an Oregon trial, continued appli- is 15:1. For example, when tissue nitro- cation of boron reduced yields 2 years in 5 gen is 3 percent, a 15:1 nitrogen-to-sulfur when tissue boron was adequate. ratio would mean 0.2 percent sulfur. For a Do not apply boron to the soil in bands 3 percent tissue nitrogen concentration, a along the berry rows. Either broadcast tissue sulfur concentration of 0.1 percent boron or apply it as a foliar spray. Broad- would create an N:S ratio of 30:1. Sulfur cast solid boron-containing fertilizers is likely to be deficient if the N:S ratio is throughout the plantation to avoid high greater than 20:1. When using the ratio concentrations within the crop rows. Foliar approach to estimate S sufficiency, be sure boron applications in fall or spring prior to that tissue nitrogen and sulfur are not both low.

Table 12. Boron recommendations for red raspberries.

If soil B test value is1 If tissue B is2 Apply this amount of B (ppm) (%) (lb/acre) Below 0.5 Below 25 2.0-2.5 0.5-1.5 25-30 1.0-2.0 Over 1.5 Over 30 0 1 Preplant hot water extractable soil test. 2Late-July to early-August tissue test (for established crops).

58 Chapters. Plant Nutrition Management

bloom are effective. Boron can be added soil acidity (the hydrogen ion concentra- to most sprays, particularly Bordeaux tion) increases. mixture. Soil pH tells us the chemical condi- tions roots will experience. As soil pH Other micronutrients decreases, the solubility of iron, zinc, Other than boron, micronutrient appli- manganese, and aluminum increases. The cations have not been shown to increase concentration of manganese and alumi- growth or yield of red raspberries in west- num can reach levels that are toxic or at ern Oregon trials. Soils within the Pacific least inhibit root growth. Crop sensitivity Northwest vary greatly, however, and to manganese and aluminum varies, and raspberry production outside of western raspberries are moderately sensitive. Oregon may require supplemental micro- As soil pH increases, the solubility of nutrient applications to soils or plants. iron, zinc, and manganese decreases. The Iron nutrition can be complicated, par- concentration of manganese and iron can ticularly on alkaline and/or poorly drained reach levels that are deficient, causing yel- soils. Iron (Fe) concentrations in soil and lowing of leaves. tissue often correlate poorly with plant For optimum raspberry production, performance. Under certain conditions, maintain the soil pH between 6.2 and 6.8. both soil and tissue tests may show abun- Lime is added to acidic soils to raise the dant iron concentrations while the plants pH. Amendments such as elemental sulfur show symptoms of iron chlorosis —yellow are added to basic soils to lower the pH. or dead tissues between dark green veins on the leaves. Acidic soil and the need for lime Keeping soil pH values neutral to mod- Soil pH determines whether lime is erately acidic (5.6 to 7.0) and providing required. A second soil test, the lime adequate water drainage usually prevents requirement or buffer test (sometimes iron deficiency problems. On alkaline soils called SMP), provides an estimate of the where iron and other micronutrient avail- amount of lime needed. ability is limited, foliar fertilizer applica- Lime is suggested when the soil pH is tions often are used for fruit production. 5.5 or below, or when calcium (Ca) levels are below 5 meq Ca/100 g of soil. How- Soil pH, acidity, ever, if total bases exceed 20 meq/100 g on fine-textured (clayey) soils, lime is and alkalinity probably not needed unless the pH is Acidity or pH is the most commonly below 5.2. determined chemical characteristic of Lime applications are most effective soil. Soil pH is a chemical property of when the lime is mixed with the soil. For soil that largely determines the suitability that reason, lime should be mixed into the for root growth. Acidity is a measure of soil at least several weeks before planting. the hydrogen ion concentration in a soil A lime application is effective over several solution (water held by the soil particles). years. Soil acidity or alkalinity is measured and Sandy soils to which fertilizers have not expressed as soil pH on a scale from 0 to been recently applied sometimes record 14. Soil pH values below 7 indicate acidic low pH and high SMP buffer values. In soils, and numbers above 7 indicate basic such cases, a light application of 1 to or alkaline soils. As pH values decrease,

59 Chapter 6. Plant Nutrition Management

2 tons lime/acre should suffice to neutral- Soil acidification ize soil acidity. While the ideal raspberry soil has a pH For acidic soils low in magnesium between about 6.2 and 6.8, commercial (less than 1 meq Mg/100 g of soil), 1 ton production is possible on sites with pH of dolomitic lime/acre can be used as a values slightly higher or lower. As soils source of magnesium (Mg). Dolomite and become alkaline (pH values above 7.0), ground limestone have about the same iron, manganese, and other micronutrients ability to neutralize soil acidity. become less available to plants. Iron chlo- After planting, monitor raspberry leaf rosis, as well as boron, manganese, and manganese (Mn) concentrations as an zinc deficiencies, can occur in raspberries indicator of declining soil pH. As soil pH grown on alkaline soils. Alkaline soils are declines, manganese availability increases common in eastern Oregon and Washing- and leaf manganese concentrations rise. If ton and in southern Idaho. leaf manganese during late July or early On mildly alkaline soils (pH about August is above 300 ppm, check the soil 7.0 to 7.5), foliar micronutrient applica- pH. tions can be used to offset soil micronutri- In established plantings, topdressing ent deficiencies. Use of ammonium sulfate is the logical method for lime applica- as a nitrogen source on soils with pH tion. Atopdress lime application should values above 6.5 can help maintain the pH not exceed 2 tons/acre. Topdressed lime within an acceptable range. moves downward Vi to 1 inch per year Attempts to lower the pH of alkaline until reaching a depth of 2 to 3 inches. soils with applications of sulfur or sulfur- Low soil pH below 3 inches will not be containing compounds have been made, corrected by topdressing lime. but with limited success. The cost of Fertilizer and Lime Materials, acidification can be high. In Utah research, FG 52-E, available from the OSU Exten- attempts to acidify alkaline soils with an sion Service, provides additional informa- acidic, iron-rich mining by-product did not tion on lime, including an explanation of reduce iron chlorosis symptoms in rasp- SMP buffer (see "For More Information," berries or strawberries. page 97).

Table 13. Approximate nutrient and water content of fresh manures.1

2 Kind of Water N P2O5 K2O manure (%) (%) (%) (%) Dairy 87 0.50 0.16 0.44 Beef 82 0.65 0.43 0.53 Poultry 73 1.30 1.02 0.50 Hog 84 0.45 0.27 0.40 Sheep 73 1.00 0.36 1.00 Horse 60 0.70 0.25 0.60 'Actual values depend on the animals' diets, environmental conditions, and how the materials are handled and stored. 2About 25 percent of the nitrogen is available the first year.

60 Chapter 6. Plant Nutrition Management

Alkaline soils often are associated with manure, assuming 1 percent N, requires alkaline irrigation water. The combination 7,000 lb/acre. Additional manure (5,000 to of natural buffering by chemicals in the 7,000 lb/acre) is required the first year, as soil and applications of alkaline irriga- not all of the nitrogen in manure is initially tion water often causes the pH to return to available. alkaline levels within a short time. Irriga- The conversion of unavailable nitrogen tion water pH can be adjusted by injecting to the available form occurs throughout various acids into the irrigation system. the growing season. If plant demand Before attempting to grow raspberries exceeds the rate of conversion, a defi- commercially on alkaline soils, have the ciency occurs. Conversely, if conversion to soil tested and determine what steps will available forms is high late in the season, be required to maintain an acceptable soil unwanted late-season growth might result. pH and adequate plant nutrition. Carefully Losses of nitrogen exceeding 50 percent consider whether the resulting crop yields can occur during manure storage or after and economic returns justify growing application to the soil surface. Nitrogen raspberries under these conditions. loss is least when fresh manure is spread and worked into the soil immediately. Manure Manure can serve as a source of weeds Manure is an excellent source of plant and pests. Unless livestock have been fed nutrients and serves as a soil conditioner. on weed-free feed, use aged manure that However, its variable nutrient content, has been composted at temperatures high handling requirements, and nutrient enough to kill seeds. release characteristics require greater Centipedelike organisms called sym- grower skill compared to commercial fer- phylans have been reported to be a prob- tilizers. Table 13 provides average nutrient lem in western Oregon when infested contents of manures. manures were applied to raspberry fields. Using manure to supply plant nutrients Symphylans feed on germinating seeds requires handling more material compared and young roots. High-temperature com- to commercial fertilizers. For example, posting should reduce problems associ- an application of 70 lb N/acre as urea ated with manure-introduced symphylans. (46 percent N) requires 152 lb material/ However, aged and composted manure acre. The same amount of nitrogen from contains lower nitrogen concentrations than fresh manure.

61 Chapter 6. Plant Nutrition Management

62 Chapter 7. Raspberry Disease and IMematode Management

Chapter 7 Raspberry Disease and Nematode Management

Red raspberry growers in the Pacific Northwest. For most diseases, the causal Northwest must be able to identify and organism, symptoms, disease cycle, control many fungal, bacterial, and viral and control measures are covered. Cul- diseases, as well as disorders caused by tural practices and other nonchemi- nematodes. Disease control in raspber- cal approaches to disease control are ries is complicated by the fact that both emphasized. current-season primocanes and second- Because pesticide regulations and regis- year floricanes generally are present. trations change frequently, this guide does Researchers estimate that diseases not recommend specific chemicals. For reduce raspberry crops by 10 to 14 per- up-to-date information on pesticides reg- cent in most years. In years when weather istered for red raspberries in this region, conditions favor fruit rots, losses can be refer to the most recent edition of the much higher. Diseases other than fruit rots Pacific Northwest Plant Disease Manage- also cause problems. Raspberry bushy ment Handbook (see "For More Informa- dwarf virus, for example, not only reduces tion," page 97). Oregon State University fruit quality due to crumbly berries but also maintains an Online Guide to Plant also requires more frequent replanting. Disease Control at http://plant-disease. To maintain yields and high fruit quality, ippc.orst.edu/ some virus-infected 'Meeker' fields are Appendix A (pages 99-100) contains a replanted after the sixth or seventh harvest calendar of activities that describes when season, as compared with about 15 years to scout for and manage pests. for healthy plants. Photos of disease symptoms are found This chapter discusses the major dis- on pages 101 and 102 (Appendix B). eases of red raspberries in the Pacific

63 Chapter 7. Raspberry Disease and Nematode Management

Use pesticides Diseases that cause tissues. Lesions on older primocanes usu- ally do not kill the canes. safely! symptoms on fruit • Wear protective Gray mold fruit rot Disease cycle clothing and Botrytis cinerea overwinters as strands safety devices as and cane Botrytis of the fungus (mycelium) in leaves and recommended {Botrytis cinerea) mummified berries and as compact masses on the label. The fungus Botrytis cinerea infects of mycelium (sclerotia) on canes. During Bathe or shower many plants and parts of plants. In red wet spring conditions, spores (conidia) are after each use. raspberry, Botrytis attacks the flowers, produced on infected plant parts. These • Read the pesti- fruit, leaves, and canes. Gray mold fruit spores are dispersed mainly by wind, but cide label—even rot is the most serious fruit disease of red some are moved about by splashing rain or if you've used raspberry in this region. Crop losses can irrigation water. The spores germinate in the pesticide exceed 50 percent in years when rains films of water on plant surfaces, and infec- before. Fol- persist through bloom and into harvest tion can occur within a few hours. low closely the and adequate fungicide protection is not Temperatures between 70 and 80oF, instructions on provided. combined with rain, dew, fog, or irriga- the label(and tion, provide ideal conditions for Botrytis any other direc- Symptoms development. The disease can develop at tions you have). Berries are partly or completely covered lower temperatures, but the plant surface with tufts of gray fungal growth (Plate 6). • Be cautious must remain wet for longer periods. In some years, only a few drupelets on a when you apply During bloom, the fungus colonizes berry become moldy —a condition called pesticides. healthy or senescing flower parts, but "spot rot." Infected berries rarely leak Know your legal rarely causes the blossoms to blight, and juice. The fungus often grows on the responsibility fruit set is not affected. Flower infections as a pesticide receptacles left after the berries are picked, remain dormant until the berries ripen. At applicator. You covering the receptacles with gray, feltlike that time, the fungus resumes activity, and spores called conidia. Uninfected recep- may be liable for rot appears. Warm, humid conditions dur- tacles normally shrivel and turn grayish- injury or damage ing harvest favor fruit rot. black. resulting from Conidia also infect leaves on both pesticide use. Control fruiting laterals and primocanes. Infected No single cultural practice provides leaves turn light brown and die. On dead adequate Botrytis control. During years leaves, B. cinerea grows down the petioles when disease pressure is low, integrating and into the canes or laterals. A brown, several cultural practices might provide shield-shape lesion around the node on the adequate control. In years with moderate cane indicates this type of infection. Under to high disease pressure, cultural practices favorable conditions, the lesions continue alone probably will not be adequate. Cul- to expand and may eventually include tivars differ slightly in susceptibility to several nodes. Cane lesions usually exhibit Botrytis, but all are susceptible, and even typical concentric "water mark" patterns relatively resistant cultivars can be dam- from fall through early spring. Black aged when disease pressure is high. sclerotia form beneath the cuticle or outer Cultural control. Sanitation provides layer of the canes. Young primocanes may few advantages because the fungus attacks be killed when lesions girdle the vascular and survives on a wide range of crop and

64 Chapter 7. Raspberry Disease and Nematode Management weed plants and plant debris. Cultural con- Phytophthora root rot trol practices include the following. {Phytophthora fragariaevar. rubi) • Create an open canopy to improve air See page 73. circulation and drying of the foliage, stems, and fruit. A divided canopy sup- Tomato ringspot virus ported on a V-trellis, with canes fas- See page 69. tened individually to the trellis instead Yellow rust of in bundles can reduce Botrytis (Phragmidium rubi-idaei) problems. Follow the pruning recom- See page 69. mendations in Chapter 5 to prevent overcrowded canes from inhibiting air circulation. Diseases that cause • Avoid excessive nitrogen fertilization. symptoms on canes • Pick fruit during the coolest part of the and leaves day. Cane blight • Pick frequently so that berries do not {Leptosphaeria coniothyrium) become overripe. The fungus Leptosphaeria coniothy- • Keep harvested berries in the shade and rium causes this cane disease. It enters the move them to refrigerated storage as primocanes only through wounds, so any soon as possible to remove field heat. practice that minimizes wounding is ben- • Control early-season primocane growth eficial. Wounds become less susceptible as mechanically or chemically (see "Pri- they heal, and primocanes are more diffi- mocane suppression," page 33). cult to wound as they become older. • Schedule overhead irrigation for early Berry-catching plates on mechanical morning just before the sun comes up harvesters are the main source of wounds so that plants dry quickly. to raspberry plants. Primocanes, particu- • Install a drip irrigation system to mini- larly those on the outside of each plant, mize wetting of plant surfaces. are scraped with each pass of a mechanical harvester. Several passes may be needed Chemical control. Refer to the Pacific before a cane is wounded deeply enough Northwest Plant Disease Management for the fungus to gain entry to the vascular Handbook for products registered for con- tissues. Cane blight rarely is a problem in trol of gray mold. hand-harvested fields. • Employ fungicide resistance manage- ment strategies, such as alternating Symptoms fungicides and tank mixtures. Pay Except for the wound itself, symptoms close attention to the fungicide mode of do not appear on the canes until fall or action group number and avoid repeated during the fruiting year. The area of the use of products from the same group. wound often is flattened and cracked. • Begin fungicide applications at early Because the fungus degrades cellulose, bloom to protect newly opening infected canes are easily broken at the flowers.

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wound. The surfaces of the cane around • Convert from overhead irrigation to a the wound turn grayish-black as fruit- drip system. ing bodies form beneath the epidermis • Remove early flushes of primo- (Plate 7). The surface appears sooty when canes (see "Primocane suppression," spores (conidia) ooze onto the cane fol- page 33). lowing rainy weather. • Convert to an alternate-year cropping Diagnostic lesions develop in the vascu- system (see page 3). lar tissue but are not visible unless the tis- sue is exposed by scraping a suspect cane • Clean and lubricate berry-catching with the blade of a knife. Healthy vascular plates frequently during harvest. tissue is moist and pale green. In contrast, • Use springs with just enough tension to dry, orange-red to brick-red lesions form close the catching plates. in the vascular tissue of diseased canes. The fungus remains in the vicinity of Chemical control the wound. The lesions, called "stripe Fungicides are registered for raspberry lesions," extend mostly above and some- cane blight, although currently registered what below the wound site. Occasionally, products do not always provide acceptable they extend the full length of the cane. control. Severely infected canes often are girdled. Crown gall Depending on the extent and location of {Agrobacterium tumefaciens vascular damage, symptoms the following spring range from failure of a few buds and A. rubi) to death of the cane above the point of See page 72. girdling. Pseudomonas blight {Pseudomonas syringae pv. Disease cycle The fungus overwinters on old cane syringae) stubs and near wounds on infected fruit- The bacterium Pseudomonas syringae ing canes. During rainy weather, conidial pv. syringae is the causal agent of this spores ooze onto the surface of the canes occasional disease of red raspberry. and can be moved to wounds by splashing Symptoms rain or irrigation water or by contaminated Symptoms first appear in early spring harvester catching plates. Ascospores as brownish, water-soaked spots on the are discharged into the air from a second leaves, petioles, and internodes of young type of fruiting body found mainly on old fruiting laterals and emerging primocanes cane stubs. The role and importance of (Plate 8). The spots become larger and ascospores in the disease are not clearly darker, with streaks extending from the understood. damaged parts into the vascular tissues. Cultural control When symptoms are severe, entire laterals and primocanes may be killed. Generally, • Remove wounded and infected canes. the observable infections and symptoms • Prune close to the ground because the cease by about mid-May. fungus overwinters on old cane stubs. Pseudomonas symptoms can be con- • Irrigate in early morning to reduce the fused with other raspberry diseases and time plants remain wet. disorders. Leaves infected by spur blight

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appear similar to Pseudomonas-infected The life span of a healthy planting is leaves, but do not blacken. The raspberry typically about 15 years. Fields with a cane borer can cause the tips of laterals to high percentage of RBDV-infected plants blacken, similar to Pseudomonas blight. and crumbly fruit are replanted every 7 to Borer-infested canes readily break off near 8 years. Some growers remove fields after the soil, and a larva often can be found in the fifth harvest season when the disease the tunnels. Some herbicides can cause has spread quickly and fruit quality has damage that mimics symptoms of Pseudo- declined. monas blight. RBDV is pollen-borne, but it does Symptoms of leaf spotting and black not kill the pollen. Flowers are routinely streaking under the bark of primocanes visited by pollen- and nectar-collect- (in the cambium layer) also occur in the ing insects, including honey bees. These autumn but are easily missed. The pres- insects efficiently move virus-laden pollen ence of symptoms in autumn often is from flowers on infected plants to flowers associated with continued cane growth due on uninfected plants, thus spreading the to excessive nitrogen fertilization, early virus. topping of primocanes, or resumption of growth following summer drought. Symptoms The virus is symptomless on the leaves Cultural control of many red raspberry cultivars. In others • Highly resistant cultivars include it causes rings and line patterns on leaves 'Chilcotin' and 'Newburgh.' 'Meeker,' and yellowing of leaf tissue between the 'Willamette,' and 'Sumner' show an veins (Plate 9). The virus causes young intermediate reaction, while 'Nootka' is drupelets to abort, leading to crumbly ber- highly susceptible. ries and a reduction in fruit quality. • Avoid overfertilization. Control Chemical control • Use certified plants known to be free of Various copper-containing fungicides the virus. are used to reduce the populations of bac- • Plant cultivars, such as 'Willamette' teria on canes and buds. and 'Chilcotin,' that are immune to the virus. 'Haida,' 'Comox,' and Raspberry bushy dwarf virus 'Heritage' are moderately resistant, and This disease is caused by raspberry 'Cowichan' may be immune. bushy dwarf virus (RBDV). The name of this disease is misleading, as infected • Plant new fields as far as possible from plants are neither bushy nor dwarfed, fields with infected plants. although primocane growth may be • Plant in large blocks to slow the move- reduced. In a British Columbia field trial ment of the virus into new plantings. when 'Meeker' plants were inoculated • Place honey bee hives in the centers of with RBDV, primocane growth was new fields, rather than along the edge, reduced by 22 percent, cane diameter by to reduce the risk of bees carrying the 14 percent, and fruit yield by 72 percent virus in from nearby fields that contain compared to uninoculated plants. infected plants.

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• Thimbleberry (Rubus parviflorus) is a weather in the fall may increase bud fail- wild host for RBDV. Remove thimble- ure the following spring. berries from areas near raspberry fields. Disease cycle Spur blight {Didymella applanata) The fungus overwinters in two types of This cane and foliar disease in caused fruiting bodies in cane lesions. Ascospores by the fungus Didymella applanata. The (sexual spores) are discharged into the air fungus attacks black raspberry, blackberry, from April through August. Conidia (asex- and raspberry-blackberry hybrids, in addi- ual spores) ooze from pycnidia through- tion to red raspberry. Spur blight results in out the summer and are disseminated by significant yield losses, particularly in vig- splashing water. Both ascospores and orous plantings when excessive nitrogen conidia can infect leaves. fertilizer is applied. Cultural control Symptoms • Remove and destroy old fruiting canes. Numerous brown, necrotic spots with yellow borders form on leaves in years • Keep plant rows narrow and avoid when rainy weather persists into late excessive fertilization. Keep the plant spring. If the disease is severe, infected canopy open to ensure rapid drying of leaves yellow and drop prematurely, often leaves and canes. causing ripening berries to wither. • If using an overhead irrigation system, Symptoms on primocane leaves irrigate early in the morning to shorten first appear by midsummer as brown, the time canes and leaves remain wet. wedge-shape lesions with yellow borders • Primocane suppression has proven (Plate 10). These spots usually are cen- helpful in controlling spur blight (see tered on a vein. The lesion starts at the tip page 33). of the leaf blade and points toward the pet- • 'Haida' and 'Chilliwack' are reported iole. The fungus grows through the petiole to have field resistance. 'Willamette' is and invades the cane, producing a brown considered tolerant. Although it is read- lesion around the bud. The lesion may ily infected by the fungus, 'Willamette' appear purple on raspberry cultivars that produces a satisfactory crop even when have a waxy bloom on the cane surfaces. disease pressure is high. Cane lesions usually appear first at nodes on the lower portions of the primo- Chemical control canes and then infect progressively higher • A delayed dormant application of lime- nodes. Lesions seem to disappear later in sulfur helps reduce the amount of over- the fall when primocanes turn brown as wintering inoculum. they mature for winter. During winter, infected areas turn • Fungicides are registered for control of silver-gray, and small, black fruiting bod- spur blight. If applied from just before ies of the fungus develop on the lesions. bloom until after harvest, they protect Buds at infected nodes are smaller and less the foliage on fruiting canes and primo- likely to grow into a strong fruiting lateral canes. If leaf infections are controlled, or spur during the fruiting year than buds cane lesions do not develop. at healthy nodes. Extended periods of mild

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Tomato ringspot virus • Fumigate the site based on the results Tomato ringspot virus (TomRSV) is of the soil test for nematodes. Postplant transmitted by the soil-borne dagger nem- applications of nematicides have not atode Xiphinema americanum and possi- been effective against the dagger nema- bly related species. Besides red raspberry, tode. For this reason, it is important the virus infects some cultivated and wild to know whether these nematodes are blackberries and raspberry-blackberry present in the soil well before planting hybrids such as 'Boysen.' The native hosts when there is time for corrective action. of TomRSV and the dagger nematode • Use certified planting stock known to be are numerous and include many common free of TomRSV. weeds such as dandelion and chickweed. • Dig out and destroy diseased plants. These plants can serve as sources of inoc- Remove five plants from either side of ulum in and around raspberry fields. infected plants. The rate of natural spread is about • Clean equipment thoroughly to remove 6 to 8 feet per year along the row, while soil containing nematodes before mov- the spread from row to row is slower. ing into other fields. An infected nematode can transmit the virus to plant hosts for several months. • Begin operations in fields that do not Soil adhering to machinery can move the contain the dagger nematode and then infected nematodes within fields and to move into fields with infested soil. other fields. In the absence of the virus, the • Control weeds. Not only are certain dagger nematode causes little direct dam- weeds hosts of the nematode and the age to raspberries. virus, but the virus can be seed-borne.

Symptoms Yellow rust The appearance of symptoms in red (Phragmidium rubi-idaei) raspberry depends on the cultivar, time of Yellow rust disease, sometimes called year, and how long the plants have been western yellow rust or cane rust, is caused infected. Symptoms usually are most by the fungus Phragmidium rubi-idaei. noticeable in newly infected plants. Leaf Severe outbreaks that occurred during the symptoms are varied and include mot- mid-1990s were attributed to the appear- tling, chlorosis, curling, and ringspotting ance of a new race of the fungus that (Plate 11). TomRSV also may cause crum- attacks 'Meeker' and to changes in cul- bly fruit. Some cultivars exhibit severe tural practices that favored rapid disease dwarfing that resembles cane symptoms of buildup. Phytophthora root rot. The fungus has a complex life cycle with five different spore stages. Differ- Control ent symptoms are associated with four • Test soil from potential raspberry sites stages. The fungus completes its life for the dagger nematode the year before cycle entirely on the red raspberry plant planting. Because of the wide host and does not need an alternate host, as do range of TomRSV, it is important to many other rust fungi. have new land (as well as ground previ- ously planted to raspberries) tested.

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Symptoms and disease cycle deeply wound primocanes serve as entry The fungus overwinters as thick-walled, points for the cane blight fungus, Lepto- resting spores (teliospores) attached to sphaeria coniothyrium. canes and leaf debris. In early spring, around the time of bud break, these spores Cultural control germinate to produce another type of spore • Historically, burying old leaves and (basidiospore) that infects newly expand- spent fruiting canes by cultivating was ing leaves. The first symptoms appear in the main means of controlling yellow spring—greenish-orange, glossy, pimple- rust. This method is not always effec- like structures (spermagonia) about 1 mil- tive, however. limeter ('/as inch) in diameter on the upper • Tie canes to the trellis after the leaves surfaces of young leaves on floricane later- have fallen in late fall or early winter. als. These structures tend to be inconspicu- Some growers prefer to tie primocanes ous unless abundant. to the trellis shortly after harvest; how- Within a few weeks, bright yellow fruit- ever, at this time of year, the primocanes ing bodies (aecia) form in one or two con- still have most of their leaves, leaving centric rings around the structures. Yellow, large quantities of overwintering spores powdery spores released from the fruiting in the tops of the plants. Infected leaves bodies lead to the formation of rust pus- also hold moisture and create an ideal tules on the lower surfaces of the leaves environment for teliospore germination from late spring through fall. These rust in early spring. In this situation, yellow pustules produce masses of powdery, pale rust begins at the top of the plant the yellow spores called urediniospores that following year, rather than starting at reinfect leaves, leading to the develop- the plant base and moving upward. ment of more rust pustules (Plate 12). This • Primocane suppression (see page 33) repeating stage of the life cycle allows the helps to control yellow rust by eliminat- disease to build up rapidly during the sum- ing susceptible tissues when sperma- mer, when environmental conditions are gonia and aecia are present on fruiting favorable, and causes most of the damage cane leaves. to raspberry plants. Leaf tissues above the rust pustules • Controlling cane vigor improves air cir- turn yellow, then brown, and eventu- culation in the plant canopy and hastens ally die. When leaves on the fruiting the drying of leaves and canes. laterals die, the developing berries fail • 'Meeker,' 'Willamette,' and 'Tulameen' to ripen. Infected leaves on primocanes are susceptible to yellow rust. Only also die prematurely, which can stunt 'Chilcotin' remained free of yellow rust primocane growth. Pustules occasionally in a field planting and laboratory inocu- form on flower sepals, red drupelets, and lation tests. 'Meeker' once was thought primocanes. to be partially resistant because the By midsummer, dark brown, teliospore- disease developed slowly on that cul- bearing fruiting bodies begin to develop tivar. Tests, however, have identified a within the rust pustules, turning the once new race of the fungus that develops as yellow pustules almost black. Severely rapidly on 'Meeker' as it does on other infected primocanes break easily when susceptible varieties. being trained to the trellis. Pustules that

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Chemical control releasing clouds of spores that are widely A delayed dormant application of liquid dispersed. lime-sulfur kills teliospores and basidio- spores on canes. This treatment probably Disease cycle is not effective in reducing the vast num- The Armillaria fungus can survive for bers of teliospores in leaf debris trapped years in soil and infested root debris. Its along the top trellis wire. Other fungicides ability to survive on dead plant material, are registered to control this disease. See which may be several feet below the soil the Pacific Northwest Disease Manage- surface, makes control difficult. Roots of ment Handbook for registered fungicides. raspberries usually are attacked when the fungus spreads from underground woody Diseases that cause material, such as pieces of old tree roots. Infection can occur when roots come in symptoms on roots contact with rhizomorphs. Armillaria root rot Cultural control {Armillariasw.) • Remove and destroy infected plants, This root disease is caused by species including as many small roots as pos- of the native soil-borne fungus Armillaria. sible. Also remove healthy plants imme- The fungus damages the roots of many diately adjacent to infected ones. Avoid economically important trees and horti- setting new plants where infected plants cultural crops. Although the disease is not were removed. common, infected plants usually die. The disease often appears in patches within • Take precautions when planting rasp- raspberry fields. berries on a site cleared of trees, shrubs, or brush. Girdle large trees and allow Symptoms them to die before removal. This Usually the first symptom is the decline hastens the decay of roots, and roots and dieback of canes. The leaves on depleted of nutrients are less likely to infected canes yellow, wilt, and die. Ini- support fungal growth when the tree tially, just one or a few canes on a plant tops are removed. Remove and burn, may be affected, indicating that only a onsite, all roots greater than 1 inch in portion of the root system or crown has diameter. Obtain a burning permit, if been damaged. required. If possible, leave the site fal- White, feltlike masses of fungal growth low for at least 1 year. Up to 4 fallow are found between the bark and the wood years are recommended. at or below the soil line. Black shoestring- • When the source of inoculum cannot like strands, called rhizomorphs, are be removed, trenches lined with plastic found among the roots. These hard fungal sheeting may prevent contact between structures can grow considerable distances crop roots and inoculum. through the soil and may be one way that • Maintain plant vigor using sound cul- the fungus spreads between plants. Rhi- tural practices. Plants may be predis- zomorphs can be mistaken for roots, but posed to attack when the soil is too dry. roots are solid and rhizomorphs are hol- Whether using overhead or drip irriga- low. In autumn, honey-colored mushrooms tion, deep irrigation is recommended. may form on the crowns of infected plants, Irrigate to fill the entire root zone.

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• Sawdust mulch made from infected and spongy (Plate 13). They first appear trees can introduce Armillaria into a in spring with the beginning of warm field. As mentioned earlier, sawdust weather and increase in size during the mulch creates other problems in rasp- summer. berry fields and is not recommended. As galls grow larger, infected canes split and dry out. Symptoms on severely Chemical control infected canes include stunting, leaf chlo- When combined with the removal of rosis, small and seedy fruit, wilting, and infected roots, soil fumigation with methyl possibly death. In fall, galls near the soil bromide has provided the best, although darken and begin to break down. still limited, control of Armillaria. The use of methyl bromide, however, is being Cultural control phased out. Refer to the Pacific Northwest • Establish plantings in uninfested soil Plant Disease Management Handbook for wherever possible. other treatment options. • Avoid fields where the previous crop Crown gall was susceptible to crown gall. Sites pre- {Agrobacterium tumefaciens viously planted to nonhost crops, such and A. rubi) as grasses, are preferred. Agrobacterium tumefaciens and A. rubi • Use certified nursery stock grown in are the two bacterial pathogens associated fields where the disease has not been with crown gall formation on Rubus. The found. pathogen is widespread in soil and can • Thoroughly inspect planting stock and infect herbaceous and woody plants from use only plants free of galls. many plant families. • Plant resistant cultivars. 'Willamette' These bacteria are wound pathogens, is highly resistant, and 'Nootka' and and infection occurs through injuries to the 'Canby' have intermediate resistance crown and roots. Natural wounds include in the absence of nematode damage. lateral root formation, leaf scars, and 'Skeena,' 'Chilliwack,' 'Coho,' and winter injury. Mechanical injuries occur 'Haida' are susceptible. during pruning, training, and harvesting. • Preplant soil solarization may be ben- Infections occurring during the first grow- eficial depending on field size, location, ing season after planting are the most and climate. Place clear plastic over severe and can stunt or kill plants. Crown well-tilled soil that has been irrigated to gall is more severe in the presence of the near field capacity. Solarize from mid- root lesion nematode and root-attacking July through late September and plant insects. the following spring. Symptoms and disease cycle Chemical control The formation of galls on the crowns or roots is the most diagnostic symptom. • A chemical to control this disease was Galls also may form at pruning wounds or registered for Oregon and Washington where canes have been injured by bending in 2004. Check the Pacific Northwest or training. Galls are a spherical mass of Plant Disease Management Handbook disorganized tissues and usually are soft for details.

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Biological control often become necrotic before the rest of • Dip the roots and crowns of raspberry the leaf dies, and the wilted leaves form planting stock into commercial suspen- flags by remaining attached to the petioles. sions ofAgrobacterium radiobacter One or a few primocanes in a plant may strain K84 or strain K1026 before die while the rest remain healthy, depend- planting. ing on the health of the portion of the root system supporting the particular canes. Phytophthora root rot Some primocanes that seem healthy when (Phytophthora fragariaevar. rubi) tied to the trellis in the fall die during the This root rot is caused by the soil-borne winter. funguslike microorganism Phytophthora Floricane collapse can occur at any time fragariae var. rubi and is the most serious during the growing season, depending on root disease of red raspberry in the Pacific the extent of root damage and environ- Northwest. It usually is associated with mental conditions. Berries on affected poor water drainage caused by heavy soils, fruiting canes are small and wither before hardpans, excessive irrigation, or similar ripening or just as they begin ripening. conditions. Soil at or very near saturation An examination of the roots generally is required for the production and dispersal reveals a lack of fine feeder roots and of infective zoospores. Saturated soil con- dead structural roots. The internal color ditions may favor activity of the pathogen of healthy roots is creamy white to tan, and, at the same time, stress the root sys- while that of infected roots is brick-red, tem. The pathogen is least active when soil cinnamon, or dark brown. A sharp tran- temperatures exceed 680F. sition zone usually is present between Other Phytophthora species also may be infected and healthy root tissues. A dark, involved. Root lesion nematode and pos- water-soaked lesion extends several sibly the dagger nematode may contribute inches up from the bases of many diseased to disease severity, particularly in northern primocanes. Washington. Cane wilting can be caused by other factors, including cane blight and crown Symptoms borer. A definitive diagnosis of Phytoph- The most visible symptom of root rot thora requires a plant clinic culture of the is the death of primocanes and fruiting fungus from infected roots or a molecular canes. The fungus attacks and kills some test to detect the pathogen. primocanes before they reach the soil sur- face. Additional infected primocanes are Cultural control removed during primocane suppression No single cultural practice or chemi- before they wilt. Wilting often coincides cal is likely to provide effective control. with the onset of hot, dry conditions. Pri- Combine several cultural and chemical mocanes usually begin to wilt from the practices in an integrated program for best tip down. The tips wilt over, exposing the results. silvery undersurfaces of the leaves. • If possible, select sites with well- Leaves on infected canes often turn drained sandy or sandy-loam soils. yellow, sometimes with reddish-brown • Modify poorly drained sites by install- streaks, become stiff and brittle, and die ing drain lines. (Plate 14). The margins of wilted leaves

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• Plant only certified planting stock or • Plant cultivars that are resistant or toler- plants propagated by tissue culture. ant to root rot. 'Chilliwack,' 'Meeker,' • For new plantations, plant on raised and 'Sumner' are moderately resistant. beds 12 to 18 inches high. On estab- In Idaho trials, 'Killarney' and 'Summit' lished fields where the raspberries are have performed well on heavily infected on flat ground, some growers have soils. 'Meeker' has some field tolerance developed raised beds by throwing 8 to once plants become established. Other 10 inches of soil from the alleys around cultivars have varying degrees of resis- the bases of dormant plants in the fall. tance to Phytophthora. Refer to Chap- Roots grow from the entire underground ter 3, "Cultivar Selection," for details. portions of new primocanes as they The development of new cultivars that push through the added layer of soil. combine resistance with desirable horti- If yearly additions of soil are made for cultural traits remains a high priority of 2 or 3 years, most of the root system regional raspberry breeding programs. will be in the raised bed, where the soil is drier during the rainy winter months. Chemical control CAUTION: Plants on raised beds • Fungicides are registered for control of require closer attention to soil moisture Phytophthora root rot in red raspberries. during the summer, as soil in the beds Some fungicides are applied to the soil, dries faster. Also, water from rain and while others are applied to the leaves overhead irrigation tends to run off the during the growing season. beds instead of percolating through • Soil fumigation can delay the onset of them. To alleviate these potential prob- root rot for several years but does not lems, many growers have changed from eliminate the problem. Fumigants used overhead to drip irrigation systems, solely for nematode control have not sometimes using two drip tapes per row. been effective against root rot. • Gypsum, incorporated at 6 tons per acre before planting, helps to suppress Phy- Nematodes tophthora activity and provides some control. Dagger nematode • If raised beds are not used, slope the (Xiphinema americanum group) soil in the alleys so that water drains The nematode Xiphinema americanum away from the plants. and related species, collectively known as the X. americanum group, feed on rasp- • Subsoil in the alleys to facilitate water berry roots and transmit tomato ringspot drainage. virus. Dagger nematodes are migratory in • Preplan! soil solarization has delayed soil and are called ectoparasites because the appearance of root rot symptoms for they live outside the roots. Only their long, about 2 years. Place clear plastic over needlelike stylets penetrate into the root rototilled soil that has been irrigated tissue to feed and transmit viruses. to field capacity. Solarize for about 8 weeks during the sunniest part of the Symptoms summer in preparation for planting the In the absence of tomato ringspot following spring. Solarization has not virus, extensive feeding by one species proven effective in Idaho's cool climate. in the group, X. bakeri, causes swellings

74 Chapter 7. Raspberry Disease and Nematode Management

and fishhook-like curling of the root tips. Symptoms Stunting of the roots leads to reduced Small, elongated, discolored lesions cane growth. The decline is similar to appear on new roots of lightly or newly that described for plants attacked by the infected plants. The fine feeder roots die as lesion nematode. Other species in the the damage increases. This damage stimu- group cause little direct root damage. See lates the formation of many fine roots and "Tomato ringspot virus" (page 69) for a witches' broom appearance. Without more information. feeder roots, the larger diameter roots are unable to take up nutrients and water and Cultural control often are invaded by secondary fungi. • Use certified planting stock from fields Aboveground symptoms are most often known to be free of the dagger nema- observed on fruiting canes and include tode and tomato ringspot virus. reduced cane number and diameter, stunt- • Plant in soil that has been tested and ing, and off-color leaves. found free of the dagger nematode. Col- lect soil samples between December Cultural control and April at least 2 years before plant- • Select sites that are free of root lesion ing. If the nematode is detected, plant a nematodes. Sample the soil 1 year shallow-rooted grass crop for 2 years. before planting to allow time for treat- The shallow roots bring the nematodes ment if lesion nematodes are detected. to the upper portion of the soil profile, Include soil and roots in samples sent where they are more easily controlled for nematode analysis. Root lesion nem- with fumigants. Planting a nonhost crop atode populations usually are highest in reduces virus inoculum because the late summer and fall. nematodes cannot reacquire the virus. • Use certified planting stock. • Nematodes are transported in soil and Chemical control water. Because infested soil can be • Preplan! soil fumigation is helpful in moved on farm machinery, always work managing this pest. fumigated and noninfested fields first Root lesion nematode before moving to nematode-infested fields. Thoroughly clean machinery [Pratylenchus spp.) after leaving infested fields. While several species of root lesion nematodes (Pratylenchus spp.) have been Chemical control associated with Rubus spp., only P. pene- • Preplant soil fumigation in the fall or trans seems to cause significant root dam- spring before planting has proven help- age. Pratylenchus penetrans is a migratory ful in controlling root lesion nematodes. endoparasite that spends part of its life in soil and part in root tissues. • Postplant soil treatments are available.

75 Chapter 7. Raspberry Disease and Nematode Management

76 Chapter 8. Integrated Pest Management of Insects, Mites, and Slugs

Chapter 8 Integrated Pest Management of Insects, Mites, and Slugs

This chapter provides information about Generally, insects appear earlier and have important insect and mite pests, slugs, more generations in warmer, longer season and snails in red raspberries in the Pacific areas than in regions where temperatures Northwest. The life cycle of each pest are cooler and the seasons shorter. is summarized, and monitoring methods Pests that have been numerous for sev- are described. General information about eral years may seem to disappear after dil- management is provided. Photos of each igent monitoring and management. There pest are found in Appendix B, pages 101- is always a chance, however, that the pests 104. Many more images can be found on will reappear. Regular, frequent, and thor- the Internet by searching on the common ough scouting of each field is crucial for or scientific name of the pest. effective pest management programs. Because pesticide regulations and reg- Appendix A (pages 99-100) contains a istrations change frequently, specific pes- calendar of activities that describes when ticide recommendations are not included to scout for and manage pests. here. For information on available pesti- cides, refer to the current Pacific North- Caterpillars: spanworms, west Insect Management Handbook (see "For More Information," page 97). For leafrollers, cutworms, help with monitoring and management, and loopers contact an Extension agent or integrated Many species of caterpillars feed on pest management consultant. raspberries, and all of them are larvae Populations of pest insects and mites representing the immature stage of moths. vary from year to year, region to region, Some species feed on buds and foliage, and farm to farm. The timing of life others web up against berries and feed on cycles also varies from region to region. them, and some drop into containers of

77 Chapter 8. Integrated Pest Management of Insects, Mites, and Slugs

Use pesticides fruit during machine harvest. The most Spanworms rarely damage raspberry safely! serious problem caused by caterpillars is flower buds because they usually finish contamination of harvested fruit. feeding before bloom. There is only one • Wear protective Caterpillars that feed on raspberries are generation of larvae per year, so span- clothing and commonly grouped into four categories: worms are not harvest contaminants. safety devices as spanworms, loopers, leafrollers, and cut- recommended worms. All types have three pairs of front Leafrollers on the label. legs located behind the head, but the num- • Orange tortrix: Argyrotaenia citrana Bathe or shower ber of hind legs differs among species. after each use. • Obliquebanded leafroller: Spanworms. Spanworms are green Choristoneura rosaceana • Read the pesti- with white stripes along the sides and • European leafroller: Archips rosana cide label—even back. They have two pairs of hind legs; if you've used the second pair is at the end of the body • Dusky leafroller: Orthotaenia the pesticide and looks like a single leg. Spanworms undulana before. Fol- and loopers crawl in a looping manner • Straw-colored tortrix: Clepsis low closely the by drawing their back legs forward and spectrana instructions on arching their body into a loop. The front Orange tortrix is the main leafroller the label(and legs are then pushed forward as the insect pest in Oregon's Willamette Valley and in any other direc- straightens out. Washington's Skagit, Clark, and Cowlitz tions you have). Loopers. Loopers also have white counties. Obliquebanded, European, and • Be cautious stripes down their sides and back, but have dusky leafrollers and straw-colored tortrix when you apply three pairs of hind legs. are more common in northwestern Wash- pesticides. Leafrollers. Leafrollers are straw- ington's Whatcom County. Leafrollers also Know your legal colored, green, or brown with a dark or are common pests in northern Idaho. responsibility light head. They have five pairs of hind Orange tortrix larvae are tan when small as a pesticide legs. Leafrollers wiggle vigorously back- (Plate 16), changing to pale green with a applicator. You ward when disturbed and do not move in a tan head as they mature. There are two or may be liable for looping fashion. three generations per year. injury or damage Cutworms. Cutworms are striped or Larvae overwinter, often in dead leaves resulting from patterned in various colors and have five on canes tied to trellises. Following a mild pesticide use. pairs of hind legs. A cutworm often curls winter, moths emerge as early as March in into a ball when touched. western Oregon and Washington, although Life cycles and feeding habits a cold winter can delay emergence until April. Emergence occurs later in cooler, Spanworms shorter season locations. Peak flights of • Bruce spanworm: Operophtem the first generation of moths occur from bruceata late April to mid-May. • Winter moth: Operophtem brumata The next generation of larvae begins emerging from eggs in late May in west- Caterpillars belonging to these two spe- ern Oregon and Washington. Generations cies are almost identical (Plate 15). The of moths and larvae overlap through the larvae hatch in early spring from eggs summer. laid in winter by wingless female moths. Larvae feed on buds and new leaves, Larvae feed mostly on foliage, rolling and rolling and tying older leaves around the webbing leaves to create feeding shelters. feeding site. Larvae sometimes also feed

78 Chapter 8. Integrated Pest Management of Insects, Mites, and Slugs

on ripe fruit. Orange tortrix larvae often Spotted cutworm has a reddish brown are the main insect contaminant at harvest head and body, and the head has two in Oregon. black bands (Plate 22). These caterpillars Obliquebanded leafroller larvae are tan are likely to feed on buds in early spring. when small and later turn leaf green with a The larvae overwinter in the soil and feed black or brown head (Plate 17). There are whenever the temperature is at or above two generations per year. 40 to 50oF. Following pupation in the soil, Very small larvae overwinter and moths emerge from May through July. resume feeding in April and May, as buds They lay eggs, and a second generation of and new leaves are growing. Larvae finish larvae feeds from June through August. feeding and pupate in May. Moths emerge, The second generation of moths is present mate, and lay eggs (Plate 18) in June. from August through October. The second generation of larvae feeds Variegated cutworms are mottled dark from June through August. Second- brown or black with a yellow lateral band generation moths emerge, mate, and lay (Plate 23). The life cycle is similar to that eggs from late July through August. Lar- of spotted cutworm. vae that hatch from summer eggs feed Bertha armyworm larvae are green, until they have molted once or twice, then gray, brown, or black with a lateral orange stop feeding and seek overwintering sites or yellow stripe (Plate 24). There are two under buds and bark on canes. generations per year, with the pupae over- European leafroller (Plate 19) overwin- wintering in the soil. Adults emerge in ters as eggs and has only one generation April, mate, and lay eggs. The larvae dis- per year. Larval emergence coincides with perse on silken threads and then feed for the first generation of obliquebanded leaf- 5 or 6 weeks until June or July. Pupation roller. Less is known about the dusky leaf- occurs in the soil, followed by the emer- roller (Plate 20), but its larval emergence gence of a second generation of adults. also coincides with the first generation of Second-generation larvae feed in late sum- obliquebanded leafroller. Straw-colored mer and fall. tortrix (Plate 21) produces two generations Zebra caterpillar, named for its color- per year, similar in timing to oblique- ful pattern of zigzagging white stripes and banded leafroller. Straw-colored tortrix is lateral yellow lines on black (Plate 25), an infrequent but increasing pest. produces two generations per year. There are conflicting reports that it overwinters Cutworms as a larva, pupa, or egg. Larvae can be • Spotted cutworm: Xestia (Amathes) found on the plants from June through c-nigrum September. Moths are present in July and • Variegated cutworm: Peridroma September. saucia Brown fruitworm larvae are reddish brown with a brown head (Plate 26). • Bertha army worm: Mamestra They produce one generation per year. configurata Brown fruitworm moths overwinter, and • Zebra caterpillar: Melanchra picta larvae are present from April through • Brown fruitworm: Eupsilia June. Speckled green fruitworm larvae are tristigmata green with five lateral white stripes and • Speckled green fruitworm: Orthosia many white speckles (Plate 27). Pupae hibisci

79 Chapter 8. Integrated Pest Management of Insects, Mites, and Slugs

overwinter in the soil. The adults emerge search for cutworm larvae. Just after dusk, in very early spring, and larvae feed dur- tap the canes and wires over a beating tray ing April and May. to detect cutworms. Place pheromone traps for orange tor- Loopers trix in the fields by April 1. Place phero- • Alfalfa looper: Autographa californica mone traps for obliquebanded leafroller • Raspberry looper: Autographa ampla during mid-May. Check the traps weekly and remove trapped moths. Plot the num- Alfalfa looper produces at least two ber of moths per week on a graph. Once generations per year, while raspberry the number of moths per week has peaked, looper produces one. Alfalfa looper expect the second generation of caterpil- overwinters as a pupa in the soil, and the lars to appear. Continue to monitor for moths are present from April through May larvae as described above. The number and June through July. The larvae feed of orange tortrix moths trapped provides from May through June and July through a conservative estimate of the potential August. Raspberry looper overwinters as infestation by orange tortrix caterpillars. a larva, pupates from May through July, The relationship between trapped oblique- and emerges as a moth during June and banded leafroller moths and subsequent July. The larvae (Plate 28) feed from June larval populations is less predictive. through the summer. Harvesting machines are excellent Monitoring monitoring tools for caterpillars and other Begin monitoring for caterpillars when contaminants. Ride the harvester and note plants leaf out in spring. Caterpillar out- what types of caterpillars come across the breaks can happen quickly, so monitor belt. every few days, if possible, during early Management through late spring. Cultural practices can reduce orange Examine buds and new growth in sev- tortrix populations. Remove overwinter- eral areas within each field for signs of ing sites by destroying old canes in the leafroller, spanworm, and cutworm feed- fall, delaying trellising until most leaves ing and damage. If leafrollers and span- have dropped, and tying canes loosely worms are present, they will be found in to the trellises. Remove woody plants damaged buds and rolled leaves. If dam- along fence rows to deprive orange tortrix age is found but caterpillars are not pres- females of egg-laying sites. ent, search the base of the plant at night There are three main times for making for cutworms. These pests feed at night management decisions about caterpillars: and return to the soil during the day. the dormant to prebloom period (March As the canopy fills in, visual inspection to mid-May); bloom to preharvest (mid- becomes more difficult. During May and May through June); and harvest (July and June, sample with a beating tray, or spread August). The actual times may be several a white sheet on the ground and tap the weeks later on cooler sites in and east of canes and wires above it. Caterpillars and the Cascade Mountains. other pests will fall onto the beating tray During the dormant to prebloom period, or sheet. the goal is to protect buds and new growth Where cutworm damage is suspected, from caterpillar feeding. During bloom to dig into the soil at the base of the plants to

80 Chapter 8. Integrated Pest Management of Insects, Mites, and Slugs

preharvest, the goal is to reduce the con- Adult raspberry beetles are small tamination of harvested fruit. During har- ('/s inch), oval, and brown (Plate 29). vest, the goal is to kill contaminants. Raspberry beetle larvae are grublike and When moths are flying and laying eggs, segmented, with tan plates. They are about you can purchase tiny parasitic wasps Vi inch long when mature. (Trichogramma) and spread them through- out the fields. Trichogramma parasitizes Life cycle and feeding habits eggs of leafrollers, cutworms, and loopers, Adult beetles emerge from the soil preventing caterpillars from emerging. and begin flying in April, with flights Trichogramma has been reported to be continuing into August. Adult damage very effective in some cases. to raspberry foliage appears as scalloped If monitoring indicates that caterpil- chew marks along leaf edges and between lars are present throughout a field or are leaf veins (Plate 30). Adults also feed on numerous in several patches in a field, developing flower buds and flower parts. consider insecticide treatments. Choose an Small, oval eggs are deposited on develop- insecticide registered for the target pest, ing buds or inside flowers and developing and respect the preharvest interval. If pol- fruit. linators are in the field, choose an insec- The larvae feed inside developing rasp- ticide that is nontoxic to bees, such as a berry fruits on the receptacles (Plate 31). Bacillus thuringiensis-based product. They occasionally feed on developing Before applying chemical insecticides, drupelets, causing deformed and discol- consider that many beneficial insects and ored fruit. Larvae drop to the soil and spiders play important roles in reducing pupate in fall. The larval stage is the com- caterpillar populations. These predators mon contaminant of machine-harvested are killed by many chemical insecticides. raspberries. Using chemical insecticides can lead to Raspberry beetles also infest other outbreaks of twospotted mites. Rubus species with flowering times similar to those of summer-bearing red Noncaterpillar insect pests raspberries. Raspberry beetle Monitoring (Byturus unicoloi) Beginning in April, inspect foliage Raspberry beetle (formerly known and developing buds for adult beetles as Western raspberry fruitworm) is dis- and feeding damage. Beetles are highly tributed throughout raspberry-growing attracted to sticky traps made from non- regions of the United States and Canada. It ultraviolet white cardboard. Such traps are is a key contaminant of machine-harvested very effective for monitoring beetle flight raspberries in northwestern Washington activity and abundance. Place traps along and in British Columbia. Handpicked ber- field perimeters adjacent to neighboring ries are also affected by raspberry beetle raspberry fields or other Rubus hosts. infestations, which reduce fruit shelf life. Tolerances for contamination by this bee- Management tle vary, depending on the harvest grade Preventive insecticides can be applied and product. prior to flowering or when 5 percent of the flowers are open, just prior to setting out

81 Chapter 8. Integrated Pest Management of Insects, Mites, and Slugs

pollinators. Integrated pest management Management strategies are being developed to offer Aphids are occasional pests and rarely alternative management options. need management if no virus is present in the area. Plant certified stock that is free Large raspberry aphid of raspberry mosaic virus, and use aphid- {Amphorophora agathonica) and virus-resistant cultivars. If the virus The large raspberry aphid occasionally is present, consider managing the aphids contaminates machine-harvested raspber- when more than two aphids are observed ries. Large aphid populations support large per cane tip. populations of predators, including lady- Predators and parasitoids can help man- bird beetles and green lacewing larvae, age aphid populations if broad-spectrum which also contaminate fruit at harvest. insecticide applications are reduced prior Aphid feeding causes wilting and defor- to harvest. Adjustments to the belt and mation of new canes and leaves, and large fan of harvesting equipment can reduce populations can defoliate raspberry plants. the degree of aphid and aphid predator Excessive honeydew (aphid excretion) on contamination. foliage and fruit can promote the growth High aphid populations can be con- of molds. Raspberry aphid is the vector of trolled with a preharvest insecticide raspberry mosaic virus, which can cause application. Additional treatments using significant yield loss, but this virus is not insecticides, insecticidal soaps, and ento- common in the Pacific Northwest. mopathic fungi help suppress aphid prob- Large raspberry aphids are Ye inch long lems at harvest. Postharvest management with a pear-shape, yellow-green body of high aphid populations may not be (Plate 32). Two protuberances (cornicles), necessary if the growing season is nearing which emerge from the end of the body, its end. distinguish aphids from other insects. Adult aphids can be winged or wingless. Root weevils • Black vine weevil: Otiorhynchm Life cycle and feeding habits sulcatus Females give live birth to female • Strawberry root weevil: Otiorhynchus nymphs through a process called parthe- ovatus nogenesis. Males are produced only in the fall. Mated females lay eggs in crevices on • Rough strawberry root weevil: raspberry canes. The nymphs emerge in Otiorhynchus rugosostriatus spring and begin to feed on new growth. • Clay-colored weevil: Otiorhynchus singularis Monitoring Black vine weevil (Plate 33), strawberry Begin monitoring for aphids in late root weevil (Plate 34), rough strawberry spring and early summer. Inspect primo- root weevil (Plate 35), and clay-colored cane tips and the undersides of leaves for weevil (Plate 36) are common and impor- aphid colonies. A beating tray is useful for tant contaminants of machine-harvested monitoring aphids and aphid predators. red raspberries in the Pacific Northwest. Root weevils belong to a subfamily of

82 Chapter 8. Integrated Pest Management of Insects, Mites, and Slugs

"broad-nosed" weevils that have chewing burrow into the soil to feed on raspberry mouthparts at the end of a long rostrum rootlets. Root weevils develop and grow (snout). These weevils have a hard, 14- to through six or seven molts. '/^-inch-long body that generally is shiny black, reddish black, or mottled sandy Monitoring to dark brown. Only females have been During bud break and development of found, and all are wingless. The C-shape floricane laterals, use a canvas- or cloth- larvae (Plate 37) are legless and have a covered beating tray to detect early-season pinkish to yellowish body, brownish head clay-colored weevil and rough strawberry capsule, and chewing mouthparts. root weevil. Sample in early morning or late evening. A typical survey might Life cycle and feeding habits include taking 10 samples from each of Root weevil larvae are adapted for 3 to 5 sites within a field. grazing small roots and girdling roots and Clay-colored and rough strawberry root stems. Larvae can live for 9 months in the weevils are adapted to cool temperatures soil, during which their feeding causes and are rarely detected during the prehar- serious injury to plant roots. vest and harvest periods when air tem- The adults generally live and lay eggs peratures exceed their activity threshold. in soil crevices during the day or drop the Notched and flagged fruiting laterals or eggs to the ground at night while feeding. chewed fruit buds indicate the presence of They commonly are active between clay-colored weevil and woods weevil. 10 p.m. and 2 a.m. The characteristic Black vine and strawberry root weevils notches left by adult feeding on leaves are active during preharvest and harvest. (Plate 38) generally do not cause economi- Notching of leaf margins from mid-May to cally important damage, although feeding late June (the preoviposition period) indi- on buds and lateral shoots by the clay- cates weevil infestations. Beetles feed on colored weevil can reduce yields. foliage at night, so search with a flashlight One generation is produced each year, and beating tray to identify species and and the life cycle is similar for all spe- their relative population levels. Or, spread cies of Otiorhynchus. Most root weevils a 3-foot by 10-foot white drop cloth on overwinter as late-stage larvae or prepu- either side of the row and shake the top pae in cells found about 6 inches deep in training wire vigorously about 10 times to the soil. Some weevils also overwinter as dislodge feeding weevils. late-maturing adults and emerge as viable females that begin laying eggs in late April Management or early May during their second year. Root weevil control strategies must be If not controlled, these early-emerging directed at both generations of adults dur- females can lay 600 to 700 eggs during ing their prolonged pre-egg-laying period the growing season. Females that emerge of 4 to 9 weeks. If not controlled with a in mid-May and early June from overwin- preharvest treatment, both generations of tered pupae lay about half as many eggs as weevils can become serious harvest con- the overwintering females. taminants. Eggs laid during harvest pro- The first larval emergence occurs in duce overwintering larvae and adults for early July and peaks in late September. the following season. Upon hatching, the first-stage larvae

83 Chapter 8. Integrated Pest Management of Insects, Mites, and Slugs

For machine-harvested red raspberries, Life cycle and feeding habits weevil control requires insecticides to The life cycle of the raspberry crown maintain the zero tolerance set by the pro- borer takes 2 years to complete. Moths cessing industry. A prebloom insecticide fly during daylight from mid-July through application provides effective control September. After mating, the females of clay-colored and other overwintering deposit small, dark, oval eggs along the adult root weevils. Researchers in the underside margins of raspberry leaves. Pacific Northwest recommend weevilcide The eggs hatch in the fall, and the larvae application when 1 clay-colored weevil migrate to the bases of the canes. These appears for each 10 beating tray samples. larvae overwinter in silken structures on The insecticide normally is applied to the the sides of the canes just above the soil basal portion (lower 4 feet) of the canes. line. Camouflaging debris is attached to If necessary, an over-the-row insecticide the refuges. application can be used during prebloom In spring, the larvae feed by boring to control both adult root weevils and into the soft pith of the canes, girdling raspberry beetle adults. new canes. Larval development contin- Growers typically apply a preharvest ues inside the canes and root crowns for cleanup spray to control insects through the rest of the year. The following spring, the harvest period. This practice has pro- mature larvae a little more than 1V2 inches vided excellent control of preovipositing, long migrate up the centers of the canes summer-generation weevils. and pupate about 4 inches above the soil Research is underway on several new (Plate 40). Adults emerge from the canes soil-applied insecticides that target root in July. weevil larvae. It is hoped that these prod- ucts will provide red raspberry growers Monitoring with options for dealing with overlap- During spring and fall, regularly scout ping generations, egg-laying periods, raspberry fields for areas that seem to be feeding behaviors, and labeling issues weakened. Look for spindly canes and (e.g., preharvest intervals, reentry inter- wilting primocanes. Infested canes can be vals, and insecticide rate and application easily pulled from the crown. Look for regulations). swellings at the cane's base and crown. Examine suspect canes by cutting into the Raspberry crown borer root crown and looking for tunneling and (Pennisetia marginata) frass inside the stem and crown. During Raspberry crown borer is an important the fall, watch for the blisterlike, silken pest of red raspberries in North America. refuges in which the larvae overwinter. Raspberry crown borers are clearwing Pheromone lures are available for moni- moths that closely resemble yellow jacket toring adult male flights, but the lures have wasps (Plate 39). The larvae are cream not yet proven reliable. colored with a dark head capsule. The larvae bore into raspberry canes, causing Management poor cane vigor, spindly canes, and cane Insecticides can be applied as soil death. Raspberry crown borer can limit drenches in infested fields between a region's potential for producing com- November and March to control young, mercial raspberries. Borer populations overwintering larvae. Because raspberry increase rapidly if unmanaged.

84 Chapter 8. Integrated Pest Management of Insects, Mites, and Slugs

crown borer has a 2-year life cycle, apply plant juices. They can inject salivary tox- the drenches for 2 consecutive years. No ins, enzymes, and hormonelike substances treatment should be required the third year. into the feeding puncture. Female spider mites usually lay eggs on Spider mites the undersides of leaves. The larval stage is followed by two nymphal stages. Each • Twospotted spider mite: Tetranychus juvenile feeding stage is followed by a urticae resting stage known as nymphochrysalis, • McDaniel spider mite: Tetranychus deutochrysalis, and teliochrysalis, respec- mcdanieli tively. The time required for the pest to • Yellow spider mite: Eotetranychus develop varies with temperature, humidity, carpini borealis host plant, and leaf age. Hot, dry condi- • European red mite: Panonychus ulmi tions favor spider mite outbreaks. Spider mite populations can increase Four species of spider mites are found during bloom and preharvest. Populations in red raspberries in the Pacific Northwest. vary from field to field, depending on heat The twospotted spider mite (Plate 4]) was unit accumulations and cultural practices. the only economically important spider Field populations of twospotted spider mite species reported on red raspberries mite can increase rapidly after harvest for decades. Yellow spider mite (Plate 42) through early September. was first reported in 1992. The European Yellow spider mites and twospotted red mite (Plate 43) was identified in 1995 spider mites often are found in mixed in Washington's Whatcom and Skagit populations on the same leaves during the counties. A common tree fruit species, harvest period. The yellow spider mite it occurs mostly in northwestern Wash- emerges earlier than the twospotted spider ington. It is becoming more widespread, mite. Yellow spider mites migrate from however, for reasons that are not clear. overwintering sites to foliage along the top The McDaniel spider mite (Plate 44) was trellis wires as early as April to May. They identified in 1997 in Washington's Clark also remain on primocane foliage later in County. the season than twospotted spider mites. Red raspberry responses to spider mite The population dynamics, feeding, and feeding include chlorotic (yellow or white) webbing behavior of the McDaniel spi- stippling on leaf surfaces, reduced flower der mite are very similar to those of the bud formation, reduced yield, premature twospotted spider mite. McDaniel spider leaf fall, and even plant death. High densi- mite is adapted to eastern Washington, but ties of mites can result in defoliation and responds quickly to warm summer weather leave the plants covered in dense webbing. in western Oregon and Washington. If The larvae look like small adults, but uncontrolled, this species can severely have only three pairs of legs. Nymphs also bronze and defoliate foliage during July, look like small adults but have four pairs and fruit exposed to sunlight becomes soft of legs. and misshapen. All developmental stages of spider Life cycle and feeding habits mites may be present on floricane and pri- Adult and juvenile spider mites feed mocane foliage during the harvest period. by inserting their piercing-sucking stylet By mid-August, twospotted, yellow, and mouthparts into plant tissues and removing

85 Chapter 8. Integrated Pest Management of Insects, Mites, and Slugs

McDaniel spider mites undergo natural Slugs and snails seasonal declines. Populations also are reduced at this time by predatory phyto- {Deroceras, Arion, and Helixspp.) seiid mites and predatory bugs. Slugs and snails can contaminate machine-picked raspberries, and their Monitoring feeding on foliage can reduce bud and pri- In May, begin inspecting floricane foli- mocane growth early in the growing sea- age in the middle and upper canopy. Look son. Characteristic, silvery slime trails are for emerging overwintering adults or diagnostic of these pests. newly hatched European red mite larvae. Signs include patches of stippling along Life cycle and feeding habits the upper midrib area of floricane leaves. Slugs and snails reproduce whenever Remove leaflets and examine them with conditions are cool and wet. These pests a 10X hand lens. Collect random leaf can live for several years and lay hun- samples at least every 2 weeks during May dreds of eggs each year. They feed on and June and more frequently during har- foliage on the lower parts of floricanes vest. Keep seasonal records of spider mite and primocanes as well as on developing adults, eggs, and mite predators to identify primocanes. Slugs and snails often can be trends and determine whether treatments seen at night, but they seek shelter during are necessary. daylight.

Management Monitoring If spider mite population levels rise Scout for slug and snail damage during to the threshold of 10 to 25 per leaflet in cool, wet periods. Regularly check berry June, one option is to apply a miticide flats left in the field during harvest. with a short preharvest interval. During this period of low predatory mite activ- Management ity, spider mite populations can rapidly Slugs and snails rarely require pesticide increase to 300 or more immature mites applications. Because they can contami- and adults per leaflet by September. After nate berry flats left in the field, store flats harvest, good canopy penetration and off the ground and clean flats regularly. coverage with a miticide can be difficult Keep grasses and weeds around berry because of lush foliage and primocane fields mown short. Use slug baits and pes- lodging. Well-planned and implemented ticides only if slug populations need to be integrated control strategies for spider reduced. mites can help reduce miticide applica- tions. Newer miticides are more selective for spider mite pests and safer to predatory mites and insects than older pesticides.

86 Chapter 9. Organic Production

Chapter 9

Organic Production

Throughout this guide, we have empha- produced raspberries may offer growers a sized environmentally sound practices, profitable option for processing, IQF, and beginning with site and cultivar selection. fresh markets. Until 2002, organic laws Chapters on plantation preparation and and regulations differed among certify- establishment apply equally to conven- ing agencies across the U.S., and organic tional and organic growers. Conventional farming practices and produce quality and organic fertilizer options are discussed varied greatly among growers. In addi- in Chapter 6, and Chapters 7 and 8 include tion, some farmers marketed produce as recommendations for cultural and bio- "organic" when it was not certified or did logical controls in managing diseases and not follow organic production guidelines. pests. This situation led to confusion in the Topics that are unique for organic marketplace. growers or that merit additional empha- Besides the inconsistency in rules and sis are discussed in more detail in this regulations, organic production practices chapter. Bear in mind that this production were not well understood or documented guide does not replace national certifica- by traditional scientists. Many researchers tion standards, nor does it describe all of did not include organic or nonchemical the practices and materials available to control options in their studies, and gen- organic farmers. For complete information eration of science-based information for on organic certification, contact your state organic production has been slow. department of agriculture or an organic Today, efforts by organic producers, certification agency in your region. researchers, and state and federal legis- The U.S. organic food industry has lators have produced uniform national grown at a rate of 20 to 30 percent each guidelines for growers and marketers. year for more than a decade. Organically Allowable farming practices, pesticides.

87 Chapter 9. Organic Production

and fertilizers are more clearly defined Diseases from previous crops can by law. In order to market produce as interfere with organic production. Sites "organic," farmers must comply with that have been planted to peaches, apples, national certification standards and must grapes, brambles, blueberries, and other be certified by a USDA-accredited agency. woody fruit crops may harbor crown gall Organic production encourages limited pathogens in the soil that could be trans- use of off-farm products and application of mitted to new plantings of raspberries. nonsynthetic and less toxic fertilizers and Planting raspberries following crops of pesticides than those typically used on tra- tomatoes, potatoes, peppers, eggplants, ditional farms. Organic growers typically and strawberries increases the risk of Ver- emphasize long-term sustainable produc- ticillium wilt. To reduce the risk of these tion practices. problems, document as completely as pos- Profitability can be a problem in organic sible the history of your site, particularly systems because reduced pesticide and with regard to crops grown and pesticides synthetic fertilizer inputs often are offset applied. by increased labor and machine costs. Evaluate the prospective planting site Also, some popular organic fertilizers, critically with regard to air circulation and pesticides, and soil amendments can be water drainage. Selecting a site that allows relatively expensive to purchase or trans- cold air to drain quickly away from the port. Opportunities for grower profits lie planting reduces the risk of chronic frost in the fact that some consumers perceive and freezing injury, thereby reducing the organically grown produce to be safer for risk of crown gall. Effective air drainage themselves and the environment, and they and circulation reduce humidity around are willing to pay premium prices for such the canes, thereby reducing the risk of produce. spur blight, anthracnose, powdery mildew, fruit rots, and other diseases. Raspber- Site history ries grown on sites with wet or otherwise Previous land use is an important fac- poorly drained soils are particularly sus- tor to consider when selecting a site for ceptible to root rot. organic raspberry production. Organic certification requires that no prohibited Site preparation materials be applied within 3 years of As a general rule, spend at least 1 year certification. Some farm and orchard pes- preparing a site before planting raspber- ticides used in the 1900s, such as arsenic ries. Whenever possible, remove wild and mercury, can remain in the soil for blackberries, salmonberries, and thimble- long periods of time and make organic berries near raspberry fields to reduce the certification difficult or impossible. Before risk of transmitting pests and diseases. A purchasing land or investing in the transi- minimum of 300 to 400 feet of separa- tion to organic production, conduct soil tion from wild or cultivated berries is tests to identify potential problems with advisable. residual pesticides and other banned sub- Weeds, particularly invasive perennial stances. Likewise, determine whether pes- weeds such as quackgrass, can seriously ticide drift or runoff from adjacent farms interfere with organic raspberry produc- or pesticide-contaminated irrigation water tion. Eradicate serious perennial weeds might interfere with organic certification. before planting. Chapter 9. Organic Production

In conventional raspberry production, tilth, fertility, and moisture as discussed most weeds can be eradicated quite easily earlier in this guide. Adding large amounts before planting by using contact, trans- of bark, compost, sawdust, or other plant locatable herbicides such as glyphosate. residues to the soil seldom compensates The advantage of these types of herbicides for inherently poor soil conditions. Adding is that they have no residual soil activity. organic materials to heavy clay, for exam- When planting on a new site or transition- ple, does not improve soil drainage and ing from conventional to organic produc- can actually aggravate drainage problems. tion, growers who have serious weed On a poorly drained site, grading the site, infestations may choose to use nonorganic installing drainage tiles, and growing the herbicides to eradicate weeds before plant- crop on raised beds are more effective. ing, understanding that the farm cannot be On droughty sites with sandy soils, certified until 3 years after the final herbi- additions of organic matter can increase cide application. the water-holding capacity of the soil. Where site cleanup with herbicides is Depending on the soil, however, the vol- not desirable, combine soil cultivation, ume of organic matter required can be pro- fallowing, green manure crops, cover hibitively expensive to purchase, transport, crops, soil solarization, and hand weeding and apply. to manage weeds. These options are dis- When soil organic matter concentra- cussed in Chapter 5. tions are too low, growing green manure Organic production systems empha- crops before planting raspberries can size building high concentrations of soil be beneficial. As the green manure crop organic matter to enhance soil microbial residue degrades, it contributes organic activity, soil tilth (structure), and plant matter to the soil and can improve soil nutrition. Organic matter refers to the tilth. Generally, crops that produce large humic acids and other compounds that amounts of residue are the most popular as bind soil particles together in aggregates green manures. Such crops include cereal or clumps. Aggregate formation creates grains, sweet clover, Sudangrass, sorghum, pores in the soil that provide for root and buckwheat. Mixtures of crops, such growth, water retention and drainage, and as cereal grains and clover, vetch, or peas, gas exchange between the soil and atmo- often are used. sphere. These aggregates and pores are Some canola or mustard varieties pro- essential for root and microbial growth. duce compounds that resemble commer- Raspberries tolerate a wide range of cial soil fumigants. These fumigant-like soils with concentrations of organic matter compounds are released after the crop is ranging from very high to very low. Typi- tilled into the soil. While research into the cal agricultural soils contain around 3 to use of such crops is in the early stages, 5 percent organic matter. Sandy soils often it may be possible to use certain green contain less. Chunks of bark, straw, and manure crops to add organic matter to other visible plant and animal debris do the soil while reducing pest and disease not contribute directly to aggregate forma- organisms. tion and generally are not measured in soil Regardless of the crop chosen, do not organic matter tests. allow green manure crops to produce seed Rather than focusing solely on organic and become weeds. matter, strive to maintain soil drainage,

89 Chapter 9. Organic Production

Planting stock organisms and a notebook to record Use disease-free, certified planting observations. Pheromone traps are com- stock that is grown in accordance with mercially available for monitoring some regulations governing the production of pest populations. Scouting techniques for nursery stock. Unfortunately, finding certi- specific pests are discussed in Chapter 8. fied organic raspberry nursery stock can Using a mix of cultural practices and be difficult. If the grower can document organically allowable pesticides generally that organic stock is not available, conven- is more effective than relying on a single tional nursery stock may be used and the strategy. Cultural practices for pest man- first-year crop may be certified organic. agement are discussed in Chapters 7 and 8. Because interpretations of regulations change, check with your certifying agent Obtaining organic to confirm what types of planting stock certification can be used by organic growers. For information on organic certifica- tion, contact your state Department of Pest and disease Agriculture or local Extension office. An management application for certification requires site Select varieties that are most resistant information, including acreage, cropping to diseases. Because organic growers history, intended crops, a farm map, and have fewer pesticide options than do con- a farm plan outlining soil and pest man- ventional growers, it is critical that pest agement strategies. A farm inspection, and disease problems be identified early, interview, and submission of chemical while they can be managed effectively. and fertilizer application records and sales Monitoring pests and diseases involves records are also required. Annual renewal inspecting fields at least weekly from early and field inspections are required to main- spring through late fall. Carry a magnify- tain certification, and sampling for pesti- ing hand lens or jeweler's loupe to identify cide residues may be required.

90 Chapter 10. Harvesting and Postharvest Considerations

Chapter 10

Harvesting and Postharvest Considerations

Raspberry harvest in the Pacific North- on smaller acreages, primarily for direct west begins in late June or early July and sale to local fresh markets, and almost all lasts for about 3 to 8 weeks, depending on fruit is hand harvested. the area and cultivars grown. In primo- The shift to mechanical harvesting cane-fruiting cultivars, the second harvest occurred primarily due to labor costs. occurs from July through September, Hand harvesting can account for up to depending on cultivar and weather condi- two-thirds of the total labor cost for fruit tions. Because raspberries are fragile, have production. When migrant labor was inex- a short shelf life, and ripen over several pensive and abundant, hand harvesting weeks, frequent picking is necessary. was feasible. With changes in immigra- While careful harvesting is important for tion policies and regional economies, farm all crops, it is especially important for labor pools have declined. Growers must raspberries. Once picked, the berries must pay far more for wages, housing, educa- be kept as cool as possible and transported tion, and health benefits than ever before. quickly to processors or refrigerated Facing increased labor costs and competi- facilities to prepare them for shipment to tion from other states and countries, many consumers. Oregon and Washington raspberry growers adopted mechanical harvesting systems. A Mechanical harvesting typical mechanical harvester with 1 opera- The 1987 edition of this guide focused tor and 4 field graders can do the work of primarily on hand harvesting. Much has 80 to 85 hand pickers. changed since then. Today, more than Aside from decreased labor costs, 90 percent of the raspberries produced in mechanical harvesting has other advan- Washington and Oregon are mechanically tages. Harvesting machines can operate at harvested. In Idaho, raspberries are grown night when hand picking is not practical.

91 Chapter 10. Harvesting and Postharvest Considerations

The lower nighttime temperatures and or brittle machine harvest poorly (see higher humidity help keep fruit quality Chapter 3). high. Damage to fruit during harvesting was Compared with hand-harvested fruit, more common and severe using early- machine-harvested raspberries may be generation machines and training systems. more uniformly ripe. With hand picking, Today, machine-harvested fruit quality many berries are harvested before they is quite good. Nonetheless, mechanically are completely ripe; thus, they have not harvested raspberries are not suited for reached their full size and quality. Properly fresh market sales. adjusted mechanical harvesters primar- Pest control generally is more important ily remove fully ripe fruit that has formed with machine-harvested crops than hand- an abscission zone between the fruit and harvested crops. Beetles, caterpillars, and receptacle. Increased fruit uniformity other insects can become serious contami- translates into berries that are larger, better nants as they are shaken from the canes colored, and have lower acidity and higher into the harvester. In organic production total soluble solids. systems, insects and predators that might Mechanical harvesters do have dis- otherwise be considered beneficial can end advantages. All require significant capi- up as contaminants in a machine-harvested tal investments and ongoing expenses product. Specific pests and control prac- for maintenance and repair. Alternatives tices are discussed in Chapter 8. to purchasing equipment exist, how- Various mechanical raspberry harvest- ever. Some companies lease machines, ers are commercially available, although and some growers do custom machine- most operate similarly. Before investing in harvesting work. planting stock, trellises, irrigation systems, Machine harvesting reduces a grower's and equipment, consult with harvester flexibility in terms of cultural practices manufacturers to select a harvester and and fruit usage. Row spacing and trel- design an operation compatible with that lises must be designed with the harvesting equipment. equipment in mind. Generally, this means Mechanical harvesters can be tractor using a narrow "I" trellis without cross drawn or self propelled. Larger machines arms. Although machine harvesting is pos- usually are self propelled. The machine sible with hedgerows, most Pacific North- straddles the raspberry row, so that the west growers who harvest by machine use canes are in a narrow opening running the hill systems and arc training. Alleys must length of the machine (photo, page 91). be maintained so as to support the harvest- Rows of flexible horizontal bars or "fin- er's large wheels and prevent excessive gers" (also called "beaters") on each side compaction. Irrigation must avoid creating of the crop row gently shake the fruiting muddy alleys that could interfere with har- laterals, trellis wires, and canes, causing vester movement and operation. Finally, the ripe fruits to drop off. Inclined catch damage to canes by mechanical harvesters plates about 12 to 15 inches above the has greatly increased the incidence of cane ground collect the falling fruits. From the blight. plates, the berries travel on conveyor belts Cultivars must be suited to mechanical across screens, where fans remove some harvesting. Raspberry cultivars with fruit- contaminants. The fruits then are car- ing laterals that are too short, too long, ried across a short inspection belt, where

92 Chapter 10. Harvesting and Postharvest Considerations

graders remove additional contaminants, The number of hand pickers required and then into flats or other containers. per acre depends on the crop load, Harvesters usually travel about 1 mile weather, and workers' skills. Five or six per hour down the rows, with the fingers pickers per acre may be enough for the shaking at 100 to 150 beats per minute. first and last pickings. The main crop Weights are used to increase beater speed likely will require 10 to 12 pickers, and as the season progresses. These adjust- the peak harvest during warm weather ments, coupled with machine harvester may require 15 to 20 skilled pickers per speed, allow a good driver to adjust pick- acre. ing severity such that only ripe fruit is Worker skill is important. A begin- removed and there is little damage to the ning picker may be able to harvest only plant or remaining crop. 40 pounds per 6-hour day. Experienced Hydraulic systems allow harvesters to pickers usually can harvest 60 pounds, and be raised or lowered to accommodate dif- highly skilled pickers may be able to har- ferent training systems. Most machines vest more than 100 pounds of red raspber- also can be tilted from side-to-side to pro- ries per day. vide level operation on sloping fields. The picking interval varies with the Summer-bearing red raspberries are stage of harvest, cultivar, and weather con- machine harvested every 2 or 3 days to ditions. Five or 6 days may pass between minimize loss of ripe fruit. Thus, there the first and second pickings, with 2 or may be 10 to 15 harvests per season 3 days being more common during the depending on cultivar and climate. Waiting peak season or warm weather. too long between harvests increases fruit Particularly for growers whose harvests losses on the ground. Research has shown begin in late June, the Fourth of July holi- that typical losses for machine harvest are day can be challenging when it creates 16 percent of total yield over the length of a long weekend. Advance planning is a the season. Of course, there also are losses must to prevent crop loss. Options include when raspberries are hand picked; these particularly careful picking just before the losses are estimated to be 5 to 10 percent weekend or offering bonuses for workers of total yield. who pick during the holiday. To maintain high fruit quality in har- Hand harvesting vested berries, diseased fruits should be Hand harvesting remains important removed from the canes. At a minimum, for small farms and larger operations that drop them into the centers of the alleys. A focus on high-quality, fresh market fruit better practice is to remove them from the or high-quality IQF fruit. Because of the field to prevent disease from spreading to greater harvest costs, fruits for the fresh healthy fruits still on the canes. Because market bring a substantial premium com- workers who handle both diseased culls pared with processing berries. As shown and harvestable fruits can spread fruit rot in Table 2 (page 3), processing red rasp- inoculum to healthy berries, one strategy berries in Oregon and Washington have is to have workers remove culls prior to averaged about $0.60 per pound in recent each day's harvest. Discard all moldy or years, compared with $1.50 for fresh mar- otherwise diseased or discolored fruits. ket berries. For fresh market sales, harvest only those fruits meeting color, shape, and size

93 Chapter 10. Harvesting and Postharvest Considerations

standards. Follow-up pickers can pick the on specially constructed wire or wooden remaining fruit for processing, if desired. stands. Do not allow them to contact the Raspberries are firm and cool in the ground. Keep all containers and flats as morning and are easiest to pick at that clean as possible before, during, and after time. Begin picking as early as light harvest. Keep filled flats out of the direct allows and the dew is off the berries. sun and transport them to a refrigerated Avoid harvesting during high tempera- room as quickly as possible. tures, if possible. Also avoid harvesting To ensure that consumers receive high- wet fruit, which rots quickly. quality raspberries, shippers and larger Before entering the field, each picker growers bring all flats to a central house should receive cards marked with his or where they are inspected and may be her name. When a flat is filled, the worker weighed. Berries from randomly selected places a card in the flat to identify who baskets or clamshells are poured out and picked it and to receive credit for picking inspected to ensure they meet minimum those berries. Bar-coded cards and com- standards for size, color, shape, and other puter scanners often are used, allowing factors. If too many berries fail to meet rapid and accurate tallies of how much the standards, the flats in that lot may be fruit each picker has harvested. rejected or receive lower prices. Because Take the time to train pickers before every flat can be traced to a specific they begin harvesting. Instruct pickers to picker, quality problems can be quickly remove raspberries by grasping the ber- identified, additional training provided, or ries lightly between the thumb and two unsatisfactory workers replaced. forefingers and using a twisting motion, Pickers are paid by the pound or by rather than a pull or jerk. Pick with hands the flat. In general, payment by the flat together and palms up to catch falling provides better results for growers. Either berries. Avoid squeezing the berries by way, an inspector should examine each flat picking too many before transferring the to ensure it meets weight, cleanliness, and fruit to the picking container. Work from fruit quality standards. Each clamshell or the outsides of the canes inward and avoid basket must be filled to the correct depth. damaging remaining fruits. Inexperienced pickers often have difficulty In the past, raspberries were picked judging ripeness, and dishonest workers into buckets attached to pickers' belts have been known to place rocks in the and later poured into flats for sale. Today, bottoms of flats to increase weight. Being most fresh fruit is harvested directly into able to identify who picked each flat helps half-pint containers for sale to consumers. eliminate quality problems. Wooden or cardboard half-pint baskets have largely been replaced by clear plastic Sanitation concerns clamshell containers. Pickers are respon- In the past, fruit pathogens were the pri- sible for harvesting only market-quality mary concern during harvest. With recent berries and filling the picking containers outbreaks of E. coli and other human to the correct level. Provide check stations diseases associated with fresh and pro- in the fields so that pickers do not have to cessed fruits, sanitation has taken on a new carry filled flats long distances. importance. Standard flats hold 12 half-pint baskets Any worker who shows signs of illness or clamshells. The flats can be supported should be excluded from fruit handling

94 Chapter 10. Harvesting and Postharvest Considerations

areas and from contacting anything that Once picked, transport fresh-market will come into contact with the fruit. berries rapidly to inspection rooms, as Symptoms to watch for include open sores described above. For every 10 flats, for or wounds, vomiting, diarrhea, sore throat, example, a basket or clamshell typically is coughing, sneezing, and jaundice. Animals pulled from a flat and the berries poured and children are also potential sources onto a table for inspection. Leave all other of pathogen transmission and should, as berries in their original baskets and flats, much as possible, be excluded from fruit labeled with the grower's or broker's name handling areas. and advertising information. The most common source of fruit con- Except for the smallest operations, the tamination is unsanitary worker conditions flats are placed inside refrigerated rooms that lead to contamination with human containing rows of large, high-powered wastes. Provide workers with adequate fans along one wall. Carefully stack the rest facilities, including drinking water, flats in rows in front of the fans, and clean toilets, well-stocked hand washing cover the tops of the stacks with a clean units, and lunch shelters. According to tarp. Each flat contains vent holes in the the U.S. Occupational Health and Safety sides and ends that allow cool air drawn Administration (OSHA), 1 portable toilet from the fans to flow through and around must be provided for every 20 workers and the berry-filled containers. The goal is to must be kept within 0.25 mile of the work- lower the fruit temperature to about 32 to ers at all times. The toilets must never be 340F within 2 hours of picking. emptied while in the field. Maintain relative humidity within the One option is to equip a tractor-drawn refrigerated room at 85 to 95 percent, but trailer with portable toilets, sinks, hand keep free moisture on the berries or in the soap, drinking water dispensers, dispos- containers to a minimum. Unlike apples able towels and cups, and waste contain- and some other fruits, fresh market rasp- ers. As the workers move through the berries are not washed or cooled in water fields, the trailer can be moved with them. (hydrocooling) after picking and before Keep picking flats, containers, pallets, shipment to consumers. To reduce fruit and plastic films used to wrap pallets clean rot, the berries must be kept dry. and free of rodents and other animals. Controlled-atmosphere (CA) storage of Keep fruit handling spaces and equipment apples has developed to the point that high clean and sanitize them daily using disin- fruit quality can be maintained for months fectants suitable for a food-handling area. after picking. Refrigeration, combined with careful manipulation of oxygen, Postharvest care carbon dioxide, and ethylene gas concen- Raspberries are among the most per- trations, reduces fruit respiration and pre- ishable fresh fruits. Picking during cool vents the apples from over ripening. temperatures and shielding the harvested In recent years, great advances have fruits from direct sun are the first steps in a been made in controlled-atmosphere stor- closely controlled process to maintain high age of raspberries and other small fruits. fruit quality. Prompt delivery to a process- Instead of controlling the atmosphere in ing plant is critical for machine-harvested large rooms, however, efforts are focused fruit. on individual pallets. Once the fruit is cooled to around 32 to 340F, the flats are

95 Chapter 10. Harvesting and Postharvest Considerations

stacked onto pallets. The flats on the pal- to consumer table, is critically important lets are then wrapped in special, semiper- in keeping fruit quality high and reducing meable, plastic film that allows some gas the spread of human and fruit diseases. exchange between the fruit and outside air. Small growers who market through Oxygen levels drop, and carbon dioxide roadside stands or direct sales to local concentrations increase. This atmosphere markets should follow as many of the slows the fruit respiration rate and dis- procedures described above as possible. courages decay organisms from grow- Keep fruit clean, dry, and cold. Handle the ing, thereby increasing the raspberries' berries as little as possible and get them to shelf life. Maintaining cold temperatures consumers quickly. throughout the process, from packing shed

96 For More Information For More Information

Acidifying Soil for Crop Production West How to Reduce Bee Poisoning from Pes- of the Cascade Mountains (Western ticides, PNW 591. 2006. H. Riedl, Oregon and Washington), EM 8857-E. E. Johansen, L. Brewer, and J. Barbour. 2004. D. Horneck, J. Hart, R. Stevens, Oregon State University, http:// S. Petrie, and J. Altland. Oregon State extension.oregonstate.edu/catalog/ University. Available only online. pdf/pnw/pnw591 .pdf http://extension.oregonstate.edu/ Laboratories Serving Oregon: Soil, catalog/pdf/em/em8857-e.pdf Water, Plant Tissue, and Feed Analysis, Acidifying Soil for Crop Production: EM 8677. Oregon State University. Inland Pacific Northwest, PNW 599-E. http://extension.oregonstate.edu/ 2007. D. Horneck, et al. Oregon State catalog/html/em/em8677/ University. Available only online. Leaf Analysis of Nutrient Disorders in http://extension.oregonstate.edu/ Tree Fruits and Small Fruits, FS 118. catalog/pdf/pnw/pnw599-e.pdf Revised 1987. R. Stebbins and Caneberries Fertilizer Guide, FG 51-E. K. Wilder. Oregon State University. 2000. J. Hart, B. Strik, and A. Sheets. Monitoring Soil Nutrients Using a Man- Oregon State University. Available only agement Unit Approach, PNW 570-E. online, http://extension.oregonstate.edu/ 2003. M. Staben, et al. Oregon State catalog/pdf/fg/fg51-e.pdf University. Available only online. Compendium of Raspberry and Black- http://extension.oregonstate.edu/ berry Diseases and Insects. 1991. catalog/pdf/pnw/pnw570-e.pdf M. Ellis, R. Converse, R. Williams, and Northern Idaho Fertilizer Guide: Blueber- B. Williamson (eds.). APS Press. ries, Raspberries, and Strawberries, Cornell Fruit Resources. http://www.fruit. CIS 815. 2000. R. Mahler and cornel 1 .edu/berry.html D. Barney. University of Idaho. Fertilizer and Lime Materials, FG 52-E. http://info.ag.uidaho.edu/ 1998. J. Hart. Oregon State University. Northwest Berry and Grape Information Available only online. http://extension. Network. http://berrygrape.oregonstate. oregonstate.edu/catalog/pdf/fg/ edu/ fg52-e.pdf Pacific Northwest Insect Management Growing Raspberries and Blackberries in Handbook. Oregon State University. the Inland Northwest and Intermoun- http://insects.ippc.orst.edu/pnw/insects tain West, BUL 812. 1999. D. Barney, M. Colt, J. Robbins, and M. Wiese. University of Idaho.

97 For More Information

Pacific Northwest Plant Disease Ordering information Management Handbook. Oregon Extension publications are available State University. http://plant-disease. from the following: ippc.orst.edu Pacific Northwest Weed Management In Idaho Handbook. Oregon State University. Agricultural Publications http://weeds.ippc.orst.edu/pnw/weeds College of Agricultural and Life Sciences Pest Management Guide for Commer- University of Idaho cial Small Fruits, EB 1491. 2005. Moscow, ID 83844-2240 A. Antonelli, L. Tanigoshi, P. Bristow, Phone: 208-885-7982 T. Miller, and C. Daniels. Washington Fax: 208-885-4648 State University. E-mail: [email protected] Promoting the Safety of Northwest Fresh Web: info.ag.uidaho.edu and Processed Berries, EM 8838. 2003. In Oregon C. Bower, S. Stan, M. Daeschel, and Y. Zho. Oregon State University. Publication Orders http://extension.oregonstate.edu/ Extension & Station Communications catalog/pdf/em/em8 838.pdf Oregon State University 422 Kerr Administration Raspberries and Blackberries: Their Corvallis, OR 97331-2119 Breeding, Diseases and Growth. 1988. Fax: 541-737-0817 D.L. Jennings. Academic Press. E-mail: [email protected] Recent Growth Patterns in the U.S. Web: extension.oregonstate.edu/catalog/ Organic Foods Market. 2002. C. Dimitri and C. Greene. Agriculture Information In Washington Bulletin No. AIB777. http://www.ers. Bulletin Office usda.gov/publications/aib777/ Cooperative Extension Soil Sampling for Home Gardens and Washington State University Small Acreages, EC 628. M. Robotham P.O. Box 645912 and J. Hart. Oregon State University. Pullman, WA 99164-5912 http://extension.oregonstate.edu/ Phone: 509-335-2857 catalog/pdf/ec/ec628.pdf Toll free: 1-800-723-1763 Weeds of the West. 2000. T. Whitson et al. Fax: 509-335-3006 Western Society of Weed Science. E-mail: [email protected] http://www.wsweedscience.org Web: caheinfo.wsu.edu

98 Appendix A. Calendar of Activities

Appendix A Calendar of Activities

This calendar lists some of the more important activities for raspberry growers in western Oregon and Washington. The actual timing varies markedly, according to a farm's location. For growers in eastern portions of the Pacific Northwest, activities may be delayed by 1 to 2 months in late winter and spring and compressed during the late summer and fall. January Service and repair equipment. Examine sprayer nozzles for wear. Prune out weak canes and old fruiting wood, if not already done. Top and tie canes. Apply manure, if practical. Confirm new plant orders and arrange for beehives. Apply dormant-season sprays for pest, disease, and weed control. February Continue January activities. Spray for crown borers if needed and not already done. Prepare and plant new fields, weather permitting. Take soil samples for nematodes from fields to be planted next year. March Apply fertilizers and herbicides. Spray for crown borers, if needed. Plant new fields, weather permitting. Complete all pruning and training. Install pheromone traps for orange tortrix. April Apply delayed dormant sprays when buds show green tips. Begin primocane suppression, if used. Begin scouting for crown gall, spanworms, and raspberry crown borers. Install sticky traps for raspberry beetles. Fertilize newly planted fields. May Continue primocane suppression or mechanically remove excess canes between hills. Begin control programs for fruit rot and spur blight. Continue scouting and management programs for caterpillar pests, aphids, root weevils, crown borers, spider mites, and raspberry beetles. Install pheromone traps for obliquebanded leafrollers. Place beehives in fields. Make second nitrogen fertilizer application. June Arrange for picking crews, machines, flats, and containers. Place new shoots inside holding wires. Irrigate to field capacity before harvest. Continue pest and disease scouting and management programs, including those for fruit and root rot, adult root weevils, aphids, caterpillar pests, spider mites, raspberry beetles, and insect contaminant pests. Harvest begins in some locations.

continues on next page 99 Appendix A. Calendar of Activities

Appendix A Calendar of Activities (continued)

July Begin or continue harvest. Continue fruit and root rot management and other pest and disease scouting programs, including those for root weevils, spider mites, and raspberry beetles. Irrigate only as needed. Collect tissue samples and submit them to a laboratory. Make third nitrogen fertilizer application to primocane-fruiting raspberries. August Continue harvest and irrigation, as needed. Cultivate and plant new cover crops. Fumigate soil to control nematodes for next spring's planting, if needed. Continue mite management program and scouting for spider mites and raspberry beetles. September Continue harvest of primocane-fruiting raspberries. Continue alley management programs. Continued irrigation may be needed in drier locations. Scout for raspberry crown borers. Order plants for spring planting. Begin pruning spent floricanes and pruning and training primocanes. October Begin removing weak shoots and old fruiting wood. In western Oregon and Washington, continue pest management programs, including those for crown borers. Collect soil samples and have them analyzed. Order fertilizers, pesticides, and other supplies and equipment for next season. Clean and winterize all equipment. Drain sprayers and irrigation systems. November Continue pruning. Service trellis systems. Apply lime, if needed. Western Oregon and Washington growers may need to continue herbicide programs. Apply soil drench pesticides for raspberry crown borers, if needed. (These sprays can be made through March.) December Apply manure. Continue pruning and trellis maintenance. Evaluate this year's operation and make plans for next season.

100 Appendix B. Color Plates

Appendix B Color Plates

Plate 1. Hedgerow-grown red raspberries. Plate 2. Hill-grown red raspberries.

Plate 3. Arc cane training. Plate 4. V trellis.

Plate 5. Normal leaves (left) Plate 6. Botrytis. Plate 7. Cane blight. and leaves with nitrogen deficiency symptoms (right).

101 Appendix B. Color Plates

Plate 8. Pseudomonas blight. Plate 9. Raspberry bushy dwarf Plate 10. Spur blight. virus.

Plate 13. Crown gall.

Plate 11. Tomato ringspot virus. Plate 12. Yellow rust.

Plate 14. Phytophthora root rot. Plate 15. Bruce spanworm. Plate 16. Orange tortrix larva.

Plate 17. Obliquebanded leafroller. Plate 18. Obliquebanded leafroller Plate 19. European leafroller. egg mass.

102 Appendix B. Color Plates

Plate 20. Dusky leafroller. Plate 21. Straw-colored tortrix Plate 22. Spotted cutworm, larva.

Plate 23. Variegated cutworm. Plate 24. Bertha armyworm. Plate 25. Zebra caterpillar.

Plate 26. Brown fruitworm. Plate 27. Speckled green Plate 28. Raspberry looper. fruitworm.

Plate 29. Raspberry beetle. Plate 30. Raspberry beetle adult Plate 31. Raspberry beetle on fruit damage. receptacle.

103 Appendix B. Color Plates

Plate 32. Large raspberry aphid. Plate 33. Black vine weevil. Plate 34. Strawberry root weevil.

Plate 35. Rough strawberry root Plate 36. Clay-colored weevil. Plate 37. Root weevil larva. weevils.

Plate 38. Adult weevil damage. Plate 39. Raspberry crown borer Plate 40. Raspberry crown borer adult. larva.

Plate 41. Two- Plate 42. Yellow spider Plate 43. European red Plate 44. McDaniel spider spotted spider mite. mite. mite. mite.

104 © 2007 Oregon State University. Pacific Northwest Extension publications are produced cooperatively by the three Pacific Northwest Land-Grant universities: Oregon State University, Washington State University, and the University of Idaho. Similar crops, climate, and topography create a natural geographic unit that crosses state lines. Since 1949, the PNW program has published more than 575 titles, preventing duplication of effort, broadening the availability of faculty specialists, and substantially reducing costs for the participating states. Published and distributed in furtherance of the Acts of Congress of May 8 and June 30, 1914, by the Oregon State University Extension Service, Washington State University Extension, University of Idaho Cooperative Extension System, and the U.S. Department of Agriculture cooperating. The three participating Extension Services offer educational programs, activities, and materials—without regard to age, color, disability, gender identity or expression, marital status, national origin, race, religion, sex, sexual orientation, or veteran's status— as required by Title VI of the Civil Rights Act of 1964, Title IX of the Education Amendments of 1972, and Section 504 of the Rehabilitation Act of 1973. The Oregon State University Extension Service, Washington State University Extension, and Univer- sity of Idaho Extension are Equal Opportunity Employers. Published October 2007. $13.50