Oilseed Production in the Northeast

OILSEED PRODUCTION IN THE NORTHEAST

A Guide for Growers of Sunflower and Canola

Dr. Heather Darby Philip Halteman Hannah Harwood Extension Agronomist Crops & Soils Crops & Soils and Instructor Technician Technician

This manual has been developed by the University of Vermont Extension Northwest Crops & Soils Program and is intended to provide the best and most broadly applicable agronomic practice information at the time of its printing. Our aim in writing is for the bulk of this manual to be as useful as possible for as long a period of time as possible. Therefore, we have designed it to address practices that are unlikely to change, while avoiding making specific recommendations for varieties or equipment. More specific information is contained in annual trial reports published in the winter and early spring, available on the UVM Extension NWCS program website (www.uvm.edu/extension/cropsoil/oilseeds). This manual will remain available as a PDF on the website as well.

OILSEED PRODUCTION IN THE NORTHEAST A Guide for Growers of Sunflower and Canola

Dr. Heather Darby Extension Agronomist

Philip Halteman Crops & Soils Technician

Hannah Harwood Crops & Soils Technician

UVM Extension helps individuals and communities put research-based knowledge to work.

Issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30, 1914, in cooperation with the United States Department of Agriculture. University of Vermont Extension and U.S. Department of Agriculture, cooperating, offer education and employment to everyone without regard to race, color, national origin, gender, religion, age, disability, political beliefs, sexual orientation, and marital or fa- milial status. Every effort has been made to make this publication as complete and accurate as possible. This text is only a guide, however, and should be used in conjunction with other information sources on crop, soil, and farm management. The editors, authors, and publisher disclaim any liability, loss, or risk, personal or otherwise, which is incurred as a consequence, directly or indirectly, of the use and application of any of the contents of this publication. Any reference to commercial products, trade names, or brand names is for information only, and nei- ther endorsement nor approval is intended.

Published March 2013

Acknowledgements

We would like to acknowledge the following individuals: Roger Rainville at Borderview Re- search Farm in Alburgh, VT; Dr. Hans Kandel with the National Sunflower Association; and all staff members of the Northwest Crops & Soils Program, including Amanda Gervais, for developing illustrations throughout the manual.

This manual was funded with generous help from the following organizations:

Table of Contents

INTRODUCTION TO OILSEED CROPS IN THE NORTHEAST 6

SUNFLOWER

1. Growth and Development 7

2. Crop Establishment and Production 10

3. Pest Management 17

4. Harvesting Practices 28

5. Seed Processing and Storage 29

CANOLA

6. Growth and Development 31

7. Crop Establishment and Production 33

8. Pest Management 38

9. Harvesting Practices 45

10. Seed Processing and Storage 46

ADDITIONAL RESOURCES 48

OILSEED CROPS IN THE NORTHEAST

Over the past decade, farm diversification has gained momentum as more and more farmers in the Northeast have looked for ways to increase farm revenue, combat declines in soil health and fertility, and cut down on operational costs. In more recent years, as the cost of petroleum products such as diesel fuel and synthetic fertilizers has increased, farms have begun to search for ways to reduce fuel, feed, and fertilizer expenses. Oilseed crops have emerged as a wel- come opportunity for many farms. Both the oil and seed meal, the two main products of the crop, have a wide variety of possible uses and markets. Sunflower and canola, two of the most common oilseed crops, can be easily incorporated into the local cropping systems, and produce added benefits such as enhanced soil health and increased biodiversity in the rotation.

Because sunflowers and canola in the United States are grown predominantly in the Great Plains, many of the technical resources are not applicable to agronomic conditions in the North- east. Additionally, there are production constraints that farmers in the Northeast face that are relatively unknown in the more common oilseed-growing regions. The University of Vermont (UVM) Extension’s Northwest Crops and Soils (NWCS) Program developed this manual to act as a collection of the best regional information for oilseed producers in the Northeast. For the past seven years, UVM Extension Agronomist Dr. Heather Darby and the NWCS Program have conducted a wide range of agronomic trials to develop locally-adapted information to aid producers in growing sunflower and canola. These trials represent a significant resource on agronomic issues such as variety selection, seeding rates, planting dates, fertility amendments, weed and pest management, and harvesting techniques.

treatment is not a substitute for waiting for better planting conditions. Organic producers are at particular risk for severely depressed germination from cold and wet soils, particularly when high levels of crop resi- dues keep soils cool and wet in the spring. Under normal conditions, emergence occurs 5-10 days after planting (Figure 1-1).

Growth Stages

The growth stages of sunflower are generally broken broadly into vegetative and reproductive stages, of which has further divisions that relate to specific developmental stages in sunflower. Table 1-1 (page 8) provides descriptions of each stage and also approximate growing degree day (GDD) units to reach each stage. Days to each stage are not given because of SUNFLOWER the extreme variability in growing season conditions in the Northeast. Being able to identify Helianthus annuus sunflower growth stages is important when attempting to identify diseases and pests, many of which affect the plant at 1. GROWTH AND DEVELOPMENT only specific development stages. This system of staging is also Germination and Emergence and 55°F. In the Northeast, important as it allows farms, sci- entists, and related industry to these conditions typically occur talk about sunflower develop- Sunflower is a fast-growing an- mid- to late-May, depending on ment on a common basis. nual plant of the Aster family elevation, soil type, soil mois- (Asteraceae) with a vast number ture and other cropping practic- of relatives native to New Eng- es. land. Like other aster-family plants, each “flower,” or head, is Sunflowers are particularly sen- made up of hundreds of individu- sitive to soil conditions during al florets attached to the recepta- the first several hours after cle, each of which is its own fully planting. Cold and wet soil at functional flower (Figure 1-3, planting can delay and lower page 9). Each disk floret produc- germination, which often in- es one seed, while ray flowers creases susceptibility of the de- are usually sterile and only serve veloping seed and shoot to fun- to attract pollinators. gal pathogens. Fungicide treated seed can improve germina- Sunflowers germinate when the tion levels in these conditions to Figure 1-1. Sunflower emer- soil temperature is between 50°F some degree, though seed gence, early June.

Figure 1-2. Growth stages of sunflower. R9 is physiological maturity.

The vegetative phase is denot- and R9 (physiological maturity) flowers by insect pollinators ed with a V, followed by the (Figure 1-2). have higher yields and higher number of true leaves greater seed oil contents. In our re- than 2” long – for example, V-4 Pollination Requirements gion, there is generally a suffi- describes when the plant has 4 cient population of insect polli- true leaves, and V-10 when the Most varieties of commercially- nators, except when insecti- plant has 10 true leaves. The available sunflowers are self- cides are used. Many of the reproductive phase is denoted compatible, which means that insect pests that present signif- with an R, followed by a num- flowers from one plant are ca- icant economic problems in ber that represents stages of pable of pollinating themselves our area appear at the same flower development and matu- and producing viable seed. time that pollinators become ration. Significant milestones in Interestingly, some studies important; spraying insecti- this phase are R2 (immature have shown that sunflowers cides becomes problematic in bud formed), R5 (flowering), that are outcrossed with other those situations.

Table 1-1. Growth stages of sunflower (Berglund, 2007). Development Description GDD units Stage VE Emergence, where only the cotyledons and/or true leaves less than 2 in. are showing 165

V-2, V-4, etc. These vegetative stages are determined by counting the number of true leaves longer than 2 350-870 in., counting any leaves that have senesced

R-1 The terminal bud produces a floral bud; bracts are visible instead of true leaves 920

R-2 The floral bud begins to elongate, but remains within 1 inch from the topmost leaf; bracts are 1250 clearly distinguishable

R-3 The floral bud continues to elongate, and is now more than 1 in. from the nearest leaf; bud re- 1395 mains tightly closed

R-4 Bud begins to open, showing immature ray flowers 1490 R-5 Flowering; sub-stages are denoted by a decimal that represents the percentage of disk florets 1545 (5.1) that have flowered (e.g. 5.1 is when 10% of florets have matured, 5.5 is when half of the florets 1625 (5.5) have matured)

R-6 Flowering complete, all disk florets mature, ray flowers withering 1780

R-7 Upper stalk and back of head begin to yellow 2050 R-8 Back of head completely yellow, but bracts still green 2210 R-9 Back of head and bracts fully brown; this is physiological maturity 2470

ture very early will most likely reduce yield potential.

When the seed reaches physiological maturity (Figure 1-4), the receptacle tissue in the head is generally still too wet to allow harvest with a combine. Dry down of the receptacle is dependent on weather conditions. Quickening dry- down of the plant with desiccants such as glyphosate is a common practice in the Great Plains, and can help avoid crop losses to birds by getting the seed out of the field before the peak of the migratory bird season. Applying a desiccant can hasten sunflower harvest by 20 days.

Figure 1-3. Anatomy of a sunflower head, showing selected plant parts.

Maturation and Senescence “medium-early,” may be the most likely to reach maturity Sunflower development is par- from year to year. Of course, ticularly dependent on accu- some areas in the Northeast mulation of GDDs, which influ- have growing seasons that will ences the rate of maturation of support the production of full the seed. Full maturity of the season varieties. In these cas- seed requires about 2500 heat es, growing varieties that ma- units, depending on the variety. In much of the Northeast, reaching 2500 heat units can be a challenge. Once the plant has reached physiological maturity it will require additional time to dry the seed and the head to a moisture content that will allow for combining. Therefore, choosing earlier to mid season varieties that dry down quickly is very important for the region. In UVM Exten- sion trials, varieties listed between 88 and 97 days to maturity, have reached harvesta- ble moistures and resulted in acceptable yields. Hence, early to full season varieties can be grown in the Northeast. However, selecting varieties that are considered “early” to Figure 1-4. Sunflower in reproductive stage, full flower. 9

2. CROP ESTABLISHMENT AND PRODUCTION

Like any other crop, establish- extremely long taproots. In- gest. ing a good stand of sunflowers deep soil, sunflowers are able requires careful attention to a to access nutrients from be- UVM Extension N fertilization variety of production practic- tween three and four feet, far rate trials (applied by top- es. This section provides below the profile of corn and dressing at approximately R-1 guidelines for managing soil hay. Many nutrients in the low- stage) have found that seed fertility, selecting varieties, er soil profiles that are lost to and oil yield vary widely with preparing the seedbed and other crops are still accessible N amendment rates between 0- planting. to sunflowers. For the most ac- 120 lbs per acre (Figure 2-1, curate information on what nu- page 11). Adapting N applica- Soils and Fertility trients are available to the tions to specific field manage- plants, we recommend taking ment conditions is crucial to Sunflowers perform well in a soil samples to a depth of two maximize yield and quality. wide variety of soil types. feet. In a UVM Extension trial, Essentially, the amount of N However, they are best-suited 30-45% of the N available to fertilizer or other organic for well-drained soils that have the plant was found in the low- amendment will depend on good water-holding capacity er half of the two-foot soil sam- your yield goal, soil type, and (i.e. high organic matter and ple (Table 2-1). past years fertility practices. good soil structure). They will Taking a nitrate sample (pre tolerate heavy, wet soils, and Nutrient Application sidedress nitrate test, PSNT) to light, excessively drained soils a two foot depth will help better than other crops, but To produce optimal yields of guide actual N needs of the yields will be lower compared sunflowers, 100 to 150 lbs of N crop during the growing sea- to sunflowers grown under per acre are required. In the son. better soil conditions. Great Plains, sunflowers generally require 5 lbs of N for Sunflowers also require rela- Sunflowers in the Northeast every 100 lbs of desired seed tively low levels of P and K. often require far less added yield (i.e. 2000 lbs of seed re- Standard soil tests will estimate soil fertility than sunflowers quires 100 lbs nitrogen). Be- available P and K in the soil. grown in the Plains. Vermont cause Vermont soils and agri- Recommendations will be pro- soils can have high levels of cultural practices differ from vided by the testing laborato- nitrogen (N), phosphorus (P), the U.S. plains region, re- ry. However, as a general rec- and potassium (K) native in the quired nitrogen rates will be ommendation, soils testing soil, as well as high levels of highly variable. For example, high to very high in P and K organic matter (>6-8%). This UVM Extension sunflower trials will require no additional input high fertility is most often asso- have yielded approximately of these nutrients. If soil test ciated with our long history of 2800 lbs per acre on average levels are low to medium, 60 to using manure as a primary with application rates of 120 100 lbs of P or K per acre will source of fertility, Sunflowers lbs N per acre or less, as op- be required to produce a sun- are exceptional scavengers of posed to the 145 lbs N the Mid- flower crop. soil nutrients because of their west rule of thumb would sug-

Table 2-1. Nitrate-N availability in the top and second foot of a soil sample. Nitrate-N Nitrate-N Total Nitrate-N Nitrate-N Sample 1 ft depth 2 ft depth Nitrate-N 1 ft depth 2 ft depth (ppm) (ppm) (ppm) (%) (%)

1 6.7 5.4 12.1 55.4 44.6 2 5.3 3.3 8.6 61.6 38.4 3 5.4 2.3 7.7 70.1 29.7 4 7.1 4.8 11.9 59.7 40.3 10

3600 1600 3300 and 3400 GDDs for the Seed yield entire growing season (May 3550 Oil yield 1550 through October), while the shortest growing seasons finish

) 3500 1500

) 1

- a

1 at just over 2,500 GDDs (Table - 3450 1450 2-2). For most of these regions, full season sunflowers would 3400 ab 1400 ab just reach physiological ma- 3350 1350 turity before the end of the b growing season, and harvest 3300 1300 would be delayed until well

3250 1250 Oilyield (lbs ac after the frost. For areas in our Seed Seed yield ac(lbs region that support sunflower 3200 1200 production, choose varieties 0 60 90 120 that are listed as “Early” or N application rate (lbs ac-1) “Medium,” or that are listed between 88 and 96 days to ma- Figure 2-1. Effects of N application rates on yields, combined 2010-2012 turity. “Full” season varieties UVM Extension data. Treatments that share a letter did not differ signifi- can be grown in areas that cantly from one another (p=0.10) in oil yield. Seed yields did not differ have exceptionally long grow- statistically by N application rate. ing seasons. It is also important to select varieties that are reported to have excellent dry Variety Selection combine. The time that it takes down. for the sunflower to dry down For our region, one of the most to adequate harvest moisture Yield Potential important decisions sunflower will partially depend on the Seed yields in sunflower are growers will make every year variety as well as the climate. determined by a large number is variety selection. There are a Vermont has a wide range of of factors, the majority of which number of varietal characteris- climatic conditions, though the are environmental. However, tics that must be considered to unifying feature is that the plant genetics also can play a make the best choice, and the growing season is much short- major role. Some varieties ex- best variety for the situation er than most other regions of hibit a greater yield potential often strikes a balance be- the continental US, and the fall than others, which is important tween yield potential, oil con- is typically wet. Some of the to know when determining tent, maturity, and resistance to longest growing seasons in which variety to plant. In gen- disease and lodging. The fol- Vermont average between eral, shorter season sunflowers lowing tips are meant to aid have slightly less yield poten- growers in selecting varieties. Table 2-2. GDD accumulation tial than longer season varie- for various locations in the ties, but this is not always the Maturity Northeast, based on historical case. Seed company charts can The most significant limiting averages (NOAA, 1981-2010). be helpful in determining the factor for growing sunflowers Weather GDD yield potential, but are difficult in our region is the shortness of Station Accumulation to accurately compare be- the growing season. On aver- Location May - Oct. tween companies. UVM Exten- age, sunflowers require about Burlington, VT 3346 sion conducts yearly variety 2,500 heat units (i.e. growing trials that provide good insight Montpelier, VT 3342 degree days) to reach physio- into which varieties are appro- logical maturity. Once the crop Rutland, VT 3093 priate for the climate and crop- is at physiological maturity it Concord, NH 3340 ping systems common to the has a moisture content of ap- Waterville, ME 3355 region (Figure 2-2, page 12). proximately 36%. Additional Worcester, MA 3352 time is required for the crop to Growing sunflowers will only reach an adequate moisture Albany, NY 3607 prove to be profitable for that allows for harvest with a Canton, PA 3165 growers if they can regularly 11

Find out more! Annual research reports available at: www.uvm.edu/extension/cropsoil/research

makes them a good multi- purpose seed. These seeds typically enter the birdseed market, but also can be used for biofuel production. High- oleic varieties, such as those with the NuSun® trait, contain a minimum of 55% oleic fatty acids, and are in high demand for the food industry for use as fry- ing oil. These oils are also good for use as cold-pressed raw oil.

Seed Size and Quality Seed quality, is important to assure uniform germination Figure 2-2. UVM Extension’s Northwest Crops and Soils Team con- rates in sunflowers. Most seed ducts variety trials to determine seed and oil yield potentials. companies report 90% as the achieve their fullest yield po- lished values, likely because of maximum germination rate un- tential; therefore, it is critical to the higher water availability in der ideal conditions, though pick a variety that has the high- our soils, which can decrease the actual germination rate de- est yield potential within the oil content of the seed. Even pends on environmental condi- limits of varieties that perform so, UVM Extension trials have tions at planting. Cold and wet well in our climate. regularly achieved oil content soils at planting can severely averages of approximately limit germination, while ideal Oil Content & Quality 33%, and often reaching 40%. conditions can raise the germi- Like yield potential, oil content nation rate by several percent- of the seed is largely based on There are two kinds of oilseed age points. Soils near 50° F are environmental factors, but ge- sunflowers which produce oils required for germination of netic potential is also signifi- with different proportions of sunflower. Most seed is treat- cant. For sunflower producers linoleic and oleic fatty acids, ed with fungicides to protect who grow for biofuel feed- and therefore have different seed from seed and seedling stock, oil content is as im- market potentials. Traditional pathogens. Organic sunflower portant as yield potential. In oilseed sunflowers tend to seed is available and is un- our region, oil yields tend to have high linoleic and low ole- treated. Therefore, it is essen- be slightly lower than pub- ic fatty acid levels, which tial to make sure planting occurs when soil conditions are ideal. Over time, germination rates of stored seed will de- Growers should select sunflower varieties that: cline, so producers should con- duct their own germination  Mature within the producer’s growing season tests for any seed stored from  Dry-down quickly in the field previous seasons before plant-  Have a high potential seed yield ing to establish an accurate es-  Have a high potential oil content timate of viability. This will help in calculating a seeding  Have desirable pest resistance traits rate for the coming year, and ordering additional seed if necessary.

ly problematic fungal disease flower variety and plan seed- for sunflowers in our region is ing dates accordingly for maxi- Sclerotinia, for which there is mum yields. not a resistant variety of sunflowers. Growers should peri- Seedbed Prep & Seeding odically ask seed distributors Sunflower seeds should be about new fungal resistance planted 1.5-2” deep into a traits. moist, even seedbed, once soil temperatures have reached 50° Herbicide Tolerance F. Like most crops, sunflowers Like disease resistance, herbi- benefit greatly from a well- cide tolerances have been prepared, even seedbed. Inat- bred into sunflower hybrids tention to seedbed preparation using traditional techniques, will cause cascading problems and are available as non-GM throughout the season, begin- traits in sunflowers. There are ning with uneven emergence, Figure 2-3. Seed size, shape and plumpness can vary. currently two herbicide toler- and ending with premature ance traits available for sun- sunflower maturation and dry- flower hybrids (Clearfield and down. Good seedbed prepara- Seed size is very important for ExpressSun). Clearfield gives tion can reduce workload producers to consider when resistance to the herbicide Be- through the rest of the season ordering seed (Figure 2-3). yond (imazamox), which can and help ensure a good crop. Sunflower seeds are assigned control several problem weeds sizes between 1 and 5, where 1 in our area, including redroot In the Plains, no-tillage sun- is the largest and 5 the small- pigweed, lambsquarters and flower production systems are est; for oilseed sunflowers, siz- velvetleaf. The ExpressSun common. In Vermont, some es 2, 3 and 4 are most common. trait provides tolerance to Ex- producers grow sunflowers in It is extremely important for press herbicide (tribenuron no-till fields with good success producers to note the seed size methyl), which provides con- as well, but it is not suitable for and calibrate planters to meet trol of many broadleaf weeds, all fields. Because sunflowers the seed size. including lambsquarters and need fairly warm soils to en- redroot pigweed. These hy- sure good germination, they Disease Resistance brids tend to be much more are generally not a good candi- Many sunflower hybrids are expensive than conventional date for no-till systems on soils bred for resistance to fungal sunflower hybrids, and so pro- that are poorly drained or have diseases. The resistance in ducers should consider other a propensity to remain cold sunflowers was developed methods of broadleaf weed late into the spring. However, through traditional breeding control, such as well-planned there are plenty of good op- techniques, and the traits have rotations, secondary tillage portunities on more moderate been obtained either from wild and cover cropping. and light soils for reduced till- sunflower or natural mutations age. Reduced tillage systems in hybrid sunflowers. There- Planting Practices can improve soil quality and fore, they are not genetically reduce crop production costs. modified (GM) crops. Of the One of the most common pro- available disease resistance duction problems in sunflower traits, the most significant for fields across the country is our area is resistance to downy planter error that leads to long mildew. Because of our high- skips or clusters in fields and humidity climate, sunflowers subsequent increased weed are more prone to fungal dis- pressure and yield losses eases here than in other re- (Figure 2-4). Many of these er- gions. Sunflower varieties re- rors can be avoided with seed- sistant to rust and Verticillium bed preparation and planter wilt are also available. The calibration. It is also crucial to Figure 2-4. Dense sunflower popu- most common and economical- consider the maturity of a sun- lation due to planting error. 13

In conventional tillage situa- oil quality. outperform a shorter season tions, field preparation is very variety at earlier planting similar to preparation for corn, It is very important to note the dates. which generally includes maturity of a sunflower variety, moldboard and/or chisel plow- as provided by the seed com- Equipment Recommendations ing, followed by secondary till- pany. Generally, early season Sunflowers should be planted age to break up large clods planting allows the farmer to with corn planters or air seed- and even out the seedbed. In- plant a longer season variety. ers. Though producers some- corporation of pre-plant herbi- Longer season varieties often times use traditional grain cides can occur at this point as yield higher due to their ex- drills, the irregular shape and well. tended growth period. If the size of sunflower seeds gener- planting date is delayed, often ally causes problems with seed UVM Extension trials have farmers must change to a short- spacing, as they get stuck in evaluated the performance of er season variety that will be the seed openings or in the sunflowers in reduced tillage able to mature during the allot- seed tubes. This poor move- and no tillage systems and ted growing season. If a longer ment of the seed results in a shown that they can yield as season variety is grown at later high percentage of skips and well as conventional tillage planting dates, it may not have doubles, resulting in competi- systems. One recurring issue enough time to properly ma- tion between plants in some in the Northeast in reduced till- ture and yield potential and spots, as well as long skips age systems is that sunflowers quality will be compromised. where weeds can become es- are not particularly competi- For example, a longer-season tablished. This can also lead to tive against weeds early in variety like Syngenta’s extremely dense clusters of their development. In reduced ‘7120’ (95 days) will have high- plants, which cannot compete and no-till systems, care must er oil yields when planted on for resources and will not grow be taken to reduce weed pres- the earliest planting date. well. sure early in the season, and in Shorter season varieties like particular, to reduce pressure Croplan’s ‘306’ (88 days) will Seed meters that use a finger from any pre-existing cover have higher oil yields at the pickup system often have inter- crop with herbicides or other latest planting date (Figure 2- changeable finger pickup means. 5). We would expect that the wheels, and sunflower-specific shorter season variety may out- fingers can be purchased rela- Planting Dates perform a later season variety tively inexpensively (Figure 2- Because sunflowers are a fairly as the planting date becomes 6, page 15). Metering systems long-season crop, it is im- delayed. Likewise, we would that employ a vacuum seed portant to plant them as soon expect a later season variety to plate also have sunflower- as the soil conditions permit. In Vermont, soil temperatures of 50°F typically occur in the second or third week of May; it is a good rule of thumb to have sunflowers planted before June 1. If a short-season hybrid is planted at this time, it will generally be ready for harvest by the first or second week of Oc- tober. Planting can extend to the first week in June, but planting later than that point introduces a significant risk that sunflowers will not reach maturity before first frost. Im- mature plants that are killed by a frost will have reduced seed- Figure 2-5. Effects of planting date on long and short season variety set, test weight, oil content and oil yields, 2011 data, UVM Extension. 14

specific plates (both flat plates and cell plates) that accommodate the unique shape of sunflower seeds. These basic adjustments provide huge improvements in seed spacing, which corresponds directly to increased yield.

Other small adjustments can be made to seeding systems within the meter that can greatly improve seed spacing. Dou- bles eliminators, or seed sin- gulators, are common in vacuum planters, and can be adjusted to be more or less aggressive to accommodate seeds of different sizes. Doubles elimi- Figure 2-6. Finger pickups designed for sunflower (left) and corn nators also exist in some finger (right). pickup meters. from those trials is that a com- oil contents. With higher plant Replacing the seed tubes that bination of talc and graphite populations, head size, seed deliver the seed from the me- greatly improved seed flow size and the number of seeds ter to the ground can also pro- through the planter, resulting per head generally decrease. vide improvements in seed in better seed placement. However, increased plant pop- spacing. The University of Ne- ulations cause oil content to braska has done numerous tri- Seeding Rates & Populations increase and plants to grow als with various seed metering Sunflower head size, height, taller to compete for sunlight systems and seed delivery sys- and seed size are influenced (Figure 2-7). tem adjustments to achieve by population density, which in ideal seed spacing (Smith, turn causes a number of other Because of the plasticity of 2011). One additional finding responses in lodging rates and many of these plant stand char- acteristics, seed and oil yields 62 8 are roughly equivalent over a A a Plant height wide range of seeding rates. AB 7 61 ABab ab However, changes in head size Lodging and seed size could have an 6 B effect on bird damage, insect 60 b 5 predation, oil content, and per- haps most notably, drying rate, 59 4 which in turn influences har- c C 3 vest date and seed drying 58 Lodging (%) time. As population increases, Plantheight (in.) 2 head width decreases, and 57 drying time is shortened. At 1 harvest time, moisture remains 56 0 higher in sunflower stands with 20000 24000 28000 30000 32000 wider heads, or lower popula- Population (plants ac-1) tions (Figure 2-8, page 16).

Figure 2-7. Effects of population on plant height and lodging, combined Harvest populations between 2010-2012 UVM Extension data. Treatments that share a letter did not dif- 28,000 and 30,000 plants per fer significantly from one another (p=0.10, compare capital letters for acre have been shown to pro- plant height and lower-case letters for lodging). vide the greatest yields in re- 15

13.8 6.2 ducing competition between a A Harvest moisture individuals and reducing weed 13.6 6.0 AB Head width pressure by achieving more 13.4 5.8 canopy closure, narrower rows 13.2 b AB can also lead to higher inci- 5.6 13.0 BC dence of fungal pathogens due c 12.8 c 5.4 to higher humidity beneath the canopy. Thirty-inch rows re- 12.6 5.2 d lieve some of the pressure of 12.4 C 5.0 fungal diseases by allowing 12.2 more air circulation while still 4.8 Head width(in.)

Harvest moisture (%) 12.0 achieving adequate yields. 11.8 4.6 Where some flexibility exists 11.6 4.4 20000 24000 28000 30000 32000 and fungal diseases are less Population (plants ac-1) threatening, narrowing the rows while maintaining the to- Figure 2-8. Effects of population on harvest moisture and head width, tal population would achieve a combined 2010-2012 UVM Extension data. Treatments that share a letter more even distribution of did not differ significantly from one another (p=0.10, compare capital let- plants across the field and can ters for harvest moisture and lower-case letters for head width). result in higher yields.

cent UVM Extension trials. Ad- Row Spacing ditionally, populations be- The standard row spacing for tween 28,000 and 30,000 plants sunflowers in our region is dic- per acre produce sunflower tated by the available planting, head sizes that are small cultivation and harvest equip- enough to dry well, but large ment, most of which operates enough to encourage bending on 30-inch rows. Though plant- over to protect seeds from ing in narrower rows confers birds. some advantages such as re-

RULE OF THUMB

In order to achieve a harvest population of 28,000 plants per acre, seeding rates must take into account the germination rate and any other expected reductions in plant population before harvest (loss from cultivation, disease, pests, etc). Gathering information like germination rate and taking note of the particular pest pressures and yield limiting factors in your fields will help you calculate an appropriate seeding rate. Producers can use the following equation to calculate the seeding rate (SR) needed to reach a desired harvest population (HP):

SR (seeds/acre) = HP (plants/acre) / [GR x (1-ASL)], where GR is the germination rate (usually 90%) and ASL is the total Anticipated Stand Loss to cultivation, pests, and disease, both expressed as decimals (90% = 0.90, 15% = 0.15).

To achieve a stand of 28,000 plants given a germination rate of 90% and an anticipated loss of 5% from cultivation and 5% from Sclerotinia head rot...

Seeding Rate = 28,000/[0.90 x (1- 0.10)] = 34,567 seeds per acre.

the best compromise for reducing fungal pressure but also keeping weeds at bay.

Planting and harvesting sunflowers earlier than normal can help avoid damage from certain pests such as banded sunflower moth and migratory birds, which only cause dam- 3. PEST MANAGEMENT age to the plant at certain times in the sunflower’s develop- Though sunflowers are a fairly field once every three to five ment. By altering the time dur- new field crop to the Northeast, years, and this is appropriate ing the season when the sun- a variety of pests already exist for the Northeast as well. flower reaches each stage, and show signs of economic Where levels of serious and these sorts of pests can be significance. Sunflower crops destructive pests are high, pe- avoided. However, because grown in research trials have riods of five to seven years are sunflowers require fairly warm shown susceptibility to weeds, recommended between suc- soils to germinate, planting insects, and diseases. Many of cessive sunflower crops until them earlier may not always be the significant pests that pressure subsides. In the feasible. Harvesting earlier, plague sunflower crops in the Plains, where sunflowers are when the combine can process Plains do not occur in our re- grown on a much larger scale, the wet head, can lessen the gion. However, those that do pests are not generally mobile damage from migratory birds, exist here can cause significant enough to move between though the added cost of dry- crop loss, and careful attention fields. In Vermont, fields tend ing seed after harvesting must to management of sunflower to be small, close together, and be considered. crops is critical to keep these surrounded by hedgerows that pests under control. This sec- can act as refuges for many Major Insect Pests tion provides identification pests. Therefore, insect and guides for major pests and fungal pests are generally able Currently, only a few insects tools for their management. to spread between fields, and are known to cause economic it is important to provide injury to sunflower crops in the The various strategies for pest enough space and time be- Northeast. However, as sun- management can be grouped tween successive sunflower flowers become more wide- into four categories: cultural, crops that movement of those spread additional insect pests mechanical, chemical and bio- pests is limited. are likely to cause damage to logical. Several tools exist this crop. Several insects that within each category, but not In addition to good rotations, have become significant pests all options make economic or other agronomic practices can in other regions are able to agronomic sense in every help reduce pest pressure. survive here, but have not yet case. As a general rule of Row spacing and stand density been seen in our sunflower thumb, preventative pest man- have a strong influence over crops. Only banded sunflower agement is far more effective the microclimate conditions moth has shown itself to cause and costs less than reactive under the sunflower canopy. serious crop injury thus far. pest management. Where plants are dense and However, sunflower midge is rows narrow, humidity near the also present, and can cause The most effective tool against soil surface can become very yield problems on a field-by- pests of all kinds is a carefully high, which provides better field basis. There are several planned rotation of sunflowers conditions for fungal infections. other common pests that do not with grass and other broadleaf As rows widen and plant spac- cause crop injury, but should crops. Virtually every producing increases, however, condi- be identified and monitored. tion guide in the U.S. recom- tions become better for weeds mends rotations that call for that can compete with sunflow- sunflowers to be planted in a er. Thirty-inch rows seem to be 17

Minor Insect Pests no real harm.

Sunflower Maggot Lygus bug Strauzia longipennis Lygus spp.

Sunflower maggot fly is small Lygus bugs, also called tar- (1/4–1/2”) and yellow with nished plant bugs, are very brown striping on the wings Figure 3-4. Sunflower maggot in common in Vermont in virtual- that forms a distinct F-shape stem pith. ly all vegetable and fruit crops near the edge. The adults (Figure 3-5, page 19). In sun- emerge from the soil in mid- to flower they feed on developing late-June and are highly active any given field, 60%-90% of flowers, which results in brown throughout the day. These plants will have 1-10 sunflower spots on the seed inside the small flies lay eggs on the stem maggots in the stalk. However, husk. While this presents a sig- of the flowers and the maggots because the pith is not respon- nificant problem for confection hatch and then burrow their sible for any movement of nu- sunflower seeds, no yield loss way into the stems, feeding on trients up and down the stalk in seed weight or oil has been the pith at the center of the or for contributing to the observed even with heavy in- stem (Figure 3-4). Infestation strength of the stalk, the sun- festations of tarnished plant rates are typically very high; in flower maggots cause the plant bug, and therefore there are

Banded Sunflower Moth Cochylis hospes

Identification & Signs of Damage The adult stage of this small moth can be identified by the dark brown stripe through the middle of the light beige-brown wings (Figure 3-1). The moths are typically 1/4” - 3/8” long as adults. Larvae are a creamy off-white, turning red and then green as they grow toward their pupal stage, and are around 0.5” by the time they emerge from the head. Banded sunflower moth damage results in empty seed hulls, where the larvae have eaten the contents and then exited through the hole at the top of the seed. Pres- ence of the larvae is revealed by loose webbing over the top of the florets in the area where the larvae are eating seeds. The lar- Figure 3-1. Adult banded sunflower vae leave the hulls intact and attached to the head, which may moth stuck on a trap. lead scouting efforts astray without careful attention to the condition of the seeds.

Life cycle Banded sunflower moths overwinter in the soil as pupae, emerging from the ground in early to mid-July over the course of 3 to 4 weeks, laying eggs within a week of emergence. They favor field edges, especially where there are grassy and shrubby field margins. Adults are most active in the early morning and late afternoon, though they can occasionally be found on the plants’ upper leaves during the middle of the day. Adults will typically lay eggs on the upper leaves and developing flower bud. As larvae hatch, they move to the interior of the bud, and begin feeding on developing florets, and eventually on seeds themselves as they grow (Figure 3-2). Their presence is difficult to detect until well into the reproductive phase (R 5.9-6.0), when larvae create loose white webbing over seeds that they have consumed. As the seeds begin to mature, larvae can be seen moving between seeds, and their exit holes can Figure 3-2. Larvae will be seen in the top of the seed husk. Larvae emerge and drop to the soil to pu- burrow into seed to pate sometime before the seeds reach physiological maturity. feed.

Sunflower Midge Contarinia schulzi

Identification & Signs of Damage Sunflower midge is a small gnat-like insect (just over 1/16”) that is difficult to spot in the field, with trans- parent wings and a tan, striped body. Maggots are very small as well (just under 1/8”), and are initially found along the edge of the sunflower head, between the bracts and the florets.

Sunflower midge maggots feed on tissue between the bracts and the head, slowly migrating into the center of the head as the florets mature. The initial result is dead tissue along the edges. As the maggots migrate into the head, their feeding causes the head to cup toward the center, and seeds will not develop properly (Figure 3-3). In severe infestations, the head will be almost completely closed, the receptacle enlarged, and there will be no seeds in the head. Damage from sunflower midge in Vermont is not widespread; most fields have only low levels of midge infestation. However, where sunflower midge does exist in high populations, significant percentages of the flowers (10-15%) can be cupped strongly enough to reduce seed development and complicate harvesting. Figure 3-3. Sunflower midge damage. Life Cycle Sunflower midge, like banded sunflower moth, overwinters in the soil as pupae, and then emerge in June and July. The adults lay eggs along the bracts, and maggots migrate toward the center as the florets mature. The larval feeding results in necrotic tissue, which, in high midge populations, can lead to strong cupping of the head and poor seed development. As the maggots grow, they drop to the ground to pupate. Some of these will undergo a second generation in the fall, but there is no damage from these maggots, since there are no longer sunflowers in the ground to serve as hosts. no established control not practical for every field. for sunflower midge. Manage- measures in oilseed sunflower. Recent research suggests that ment options are limited, delaying planting dates to ear- though rotation will help keep Management of ly June may also reduce band- midge populations fairly low, Insect Pests ed sunflower moth incidence since the adults are small and severity. enough to be limited in their Cultural Controls mobility. Banded sunflower moth is cur- No regional methods have yet rently the most problematic been developed for scouting Chemical Controls insect pest in sunflower fields Applying insecticides is not a in Vermont. It is extremely common practice in sunflow- widespread, and overwinters ers in the Northeast. One of the in our soils and field margins. main reasons for this is the lack The best management option is of equipment in the area capa- a good rotation where succes- ble of spraying plants at the sive crops are located far correct stage without damag- enough from each other that ing the crop. Most insect pests the number of moths that can that cause serious damage move between the fields is lim- reach critical life stages when ited. Deep fall plowing after the flower bud forms, or when sunflower harvest has also the plant is just starting to flow- been shown to reduce emer- er, which generally means the gence of the adults by up to plant is too tall and too delicate 80%, but that strategy can be for commonly owned equip- costly in fuel and time, and is Figure 3-5. Lygus bug. ment in our area. The sunflow- 19 ers themselves are particularly beneficial insect populations, Unlike most other sunflower sensitive at the growth stage in pest management measures growing regions, our climate is which the adult moths emerge, should take into consideration characterized by fairly wet because the buds have begun the resident insect populations growing seasons, especially in to elongate, but still have not in a field. There are many in- the spring and fall. This leads opened; they are therefore ex- secticides currently registered to high soil moistures through- posed and susceptible to dam- in Vermont for use in sunflow- out the summer, and conse- age that can reduce seed ers, not all of which control im- quently a large number of fun- yield. Nevertheless, there is portant pests. gal diseases that can present currently at least one insect problems for sunflower grow- pest that causes economic inju- Biological Controls ers. The Sclerotinia group of ry, and could warrant spraying Biological control of insect fungal diseases is particularly insecticides (Table 3-1). pests is not particularly com- devastating in all crops it in- Chemical management is lim- mon in sunflowers, and essen- fects, and sunflowers are no ited to the adult stage, because tially non-existent as an active exception. Because of our hu- the larvae are inside the head practice in Vermont and the mid climate, special attention and seeds, and thus protected Northeast. Keeping beneficial needs to be paid to managing from insecticides. insects in sunflower fields can fungal diseases of all kinds, be extremely effective against because they can also have Extreme care must be taken to insect pests; ladybeetles, lace- serious effects on other crops avoid spraying insecticides wings, and hoverflies (syrphid in the cropping system. during periods when pollina- flies) all have predatory stag- tors are present, as many of es, and feed on problematic Minor Sunflower Diseases these insecticides also kill pol- insects. linators such as honeybees. Verticillium Because sunflowers are attrac- Major Sunflower Diseases Verticillium is a common fun- tive to pollinators and many gal disease in vegetables, and

Table 3-1. Insecticides currently registered for use in Vermont sunflowers, 2013. Check with your local Ex- tension agent or State Agency of Agricutlure for up-to-date information on pesticide use. Controls: Trade name Active ingredient EPA registration numbers Banded Sun- Sunflower flower Moth Midge Baythroid XL beta-Cyfluthrin 264-840 Yes Yes Sevin 80S Carbaryl 264-316 No No Chlorpyrifos 4E AG, 66222-19, 62719-220, 34704-857, Chlorpyrifos Yes No Lorsban 4E, War- 62719-220-1381

Chlorpyrifos + lambda- Cobalt Advanced 62719-615 Yes No Cyhalothrin Chlorpyrifos + zeta- Stallion 279-9545 Yes No Cypermethrin

Tombstone, Tomb- Cyfluthrin 34704-912, 34704-978 Yes Yes Asana XL Esfenvalerate 352-515 Yes No Declare gamma-Cyhalothrin 67760-96 Yes No

Lambda-Cy EC, Si- lencer, Grizzly Z, Nufarm Lambda- 70506-121, 66222-104, 1381-211, Cyhalothrin 1EC, lambda-Cyhalothrin Yes No 228-708, 100-1112, 100-1295 Warrior with Zeon Technology, Warrior II with Zeon Technol- Cruiser 5FS Thiamethoxam 100-941 No No 20

a consistent problem in the Sclerotinia Head Rot Midwest, though it has not been positively identified in Identification & Signs of Damage Vermont sunflowers to date. It In sunflower, Sclerotinia head rot is is likely, however, that at some one of three forms of infection by the point Verticillium will become Sclerotinia fungus. This form develops an issue in our region. Many of late in the season, usually after physio- the same management con- logical maturity is reached. Early signs cepts apply to controlling Ver- of infection are given by sections of ticillium. Rotation with non- the back of the head that turn pink and susceptible crops is the best soft while the face will have a fungal tool for managing disease mass and swollen receptacle tissue problems. pushing out between and engulfing the seeds. Eventually the sunflower Downy Mildew receptacle tissue and seeds give way While downy mildew can be a to the fungus, and the head is left a serious problem in sunflowers, skeleton that contains only the sclero- especially in our wet climate, tia, the dormant fungal bodies of the the advent and use of resistant Sclerotinia fungus (Figure 3-6). Figure 3-6. Sclerotinia head rot. Note black sclerotia in- hybrids has greatly diminished side head. the potential that downy mil- Lifecycle dew can cause serious eco- Sclerotinia overwinters as small black fruiting bodies called sclerotia nomic crop loss. Hybrids that that can lie dormant in the soil for as many as six years. They resem- contain this trait are labeled ble small rocks or clods of soil. Each spring, some of the sclerotia in “Downy Mildew Resistant” or the soil germinate and release spores due to moisture or temperature “DMR”. New races of downy cues, some release spores when the roots of host plants come in con- mildew are occurring regularly tact with them, and others continue to lie dormant. These spores float and often require fungicide up to the sunflower canopy where they land on dead or decaying treatment because resistant plant tissue (usually dead florets), and grow to infect the head. Rainy varieties have yet to be devel- and humid conditions in the fall seem to be prime conditions for Scle- oped. rotinia; infection rates are higher in wet falls than in dry seasons. Once the head is fully infected, the resulting skeleton drops the fruit- Management of Disease ing bodies into the soil or they are scattered during harvest.

Cultural Controls Eliminating Sclerotinia from a heavily infested field can be new plants. As a result, yearly very difficult, but a few basic If fields are heavily infested rotations should also ensure principles will help keep new with Sclerotinia, more grass that successive sunflower fields disease-free and fungal crops should be used in place crops are not located in adja- populations in old fields under of broadleaf crops to allow cent fields. control. The best tool for man- more time for the sclerotia to aging Sclerotinia is a well- be consumed in the soil, and Chemical Controls planned rotation that employs time between sunflower crops Fungicides are common as crops that are not susceptible should be increased to six seed treatments, but are usual- (i.e. grasses) and long periods years. Sclerotia can linger in ly not sprayed after the crop between successive sunflower soils and also be difficult to re- has emerged, though several crops. For disease-free fields, move from harvested seeds fungicides are registered. The sunflower should be planted no (Figure 3-8, page 22). most common seed treatment more than every 4 years in the is a combination of the follow- same field, with other Sclero- Some preliminary research ing three fungicides: mefenox- tinia-susceptible crops and anecdotal evidence sug- am, azoxystrobin, and fludiox- (essentially all broadleaf gests that spores can spread onil. Table 3-2 (page crops) making only rare ap- several hundred feet with provides a list of registered pearances. enough concentration to infect fungicides for use in sunflow- 21

Sclerotinia Stalk and Base Rot Biological Controls The only actively applied bio- Identification & Signs of Damage logical agent for pest manage- Sclerotinia stalk rot is fairly uncommon in our area, while base rot is ment is Contans®, a fungus that nearly as common as head rot. The fungus is the same, and therefore parasitizes the dormant fungal the diseases are interchangeable and likely to change forms season- bodies of Sclerotinia. Though it to-season and plant-to-plant. Stalk and base rots generally strike as is not as effective as well- the flowering stage is coming to a close, considerably earlier in the planned rotations, Contans® is season than head rot. Both are characterized by tan lesions on the organic-certified and does re- stem, dotted with small white fun- duce the number of sclerotia in gal masses and, eventually, the soil. Contans® does not ful- black sclerotia on the outside ly eliminate them or prevent and inside of the stalk (Figure 3- Sclerotinia infestations in the 7). Without walking through the field, however, so it should not field, stalk and base rots are hard be used as a substitute for oth- to detect until they are advanced, er management tools, but can because they generally can only be helpful where Sclerotinia is be seen once the plant has died well-established. and the heads have browned.

Major Weed Pests Lifecycle

The lifecycle of stalk and base rot Broadleaves is the same as head rot, with the Broadleaf weeds can be very exception that sunflowers can contract Sclerotinia base rot difficult to control once the sun- through the roots. Additionally, flower crop has emerged, because standard broadleaf base rot can travel from plant to plant through roots that are in herbicide options will target Figure 3-7. Sclerotinia stalk rot, contact with one another, infect- sunflowers as well as weeds. with telltale black sclerotia, white Fortunately, sunflowers are ing plants along the row. fungal bodies, and tan lesions. fairly hardy and respond favor- ably to mechanical cultivation, and once sunflowers begin to ers in Vermont. All of the fungi- approach canopy closure cides listed control downy mil- (around V-8), they grow rapid- dew, which is helpful if plant- ly and easily outcompete ing non-resistant varieties, but weeds. The best conventional do not combat Sclerotinia dis- weed control strategies involve eases. pre-plant herbicides followed

Table 3-2. Fungicides registered for use in Vermont sunflowers, 2013. Check with your local Extension agent or State Agency of Agriculture for up-to-date information on pesticide use. Controls: Active EPA registration Trade name ingredient numbers Downy Sclerotinia Dynasty, Quadris Azoxystrobin 100-1159, 100-1098 Yes No Flowable Maxim 4FS Fludioxonil 100-758 Yes No Figure 3-8. Sclerotia bodies, Apron XL Mefenoxam 100-799 Yes No seen above, are often similar in size and shape to sunflower, Fosphite Phosphorus Salts 68573-2 Yes No and can be difficult to remove during cleaning. Headline Pyraclostrobin 7969-186 Yes No 22

by several cultivations to elimi- CROP ROTATION IS KEY! nate weeds. There are several particularly problematic weeds Reducing disease depends on that share many physiological careful field management. Possi- qualities with sunflower and ble four- and five-year rotations therefore thrive in fields (Figure 3-9). Management of could look something like this: these weeds is treated collec- Year Crop Susceptibility tively because of their similari- 1 Sunflower High ty in growth habit. 2 Small Grain None

3 Hay/Alfalfa Moderate Figure 3-10. Common Lambsquarters 4 Corn None lambsquarters, Chenopodium This familiar weed is character- album. ized by its alternate, triangular- Year Crop Susceptibility shaped leaves, its pale green 1 Sunflower High flowers that grow from junc- 2 Small Grain None tions between the main stem 3 Alfalfa Moderate 4 Corn None Grasses and branches, the striped ap- 5 Small Grain None In conventional sunflower sys- pearance of the main stem it- tems, grasses are not particu- self, and its tall, coarse growth larly problematic because habit (Figure 3-10). It is an an- family, and like most of its rela- there are many useful herbi- nual weed that is quick to tives, it produces huge num- cide options. However, in or- sprout on bare soil, and is bers of small seeds that sprout ganic systems perennial rhi- therefore common in almost easily. It is a deep-rooted an- zomatous grasses such as every broadleaf crop. It grows nual with a robust stem that quackgrass can cause real very quickly, and can reach survives cultivation well, espe- yield issues because they are heights of four feet or more by cially if conditions are slightly not controlled well by cultiva- the end of the growing season. wet (Figure 3-11). tion. Tineweeding can be ef- It produces thousands of seeds fective in sunflower fields to per year that are viable for reduce grass weed pressure. long periods of time in the soil. Mustards Unlike lambsquarters and red- Redroot Pigweed root pigweed, mustards are not This weed is also common- particularly coarse-stemmed, place in both broadleaf and but they have an uncommon grass crops, and is similar in ability to redirect their growth appearance to lambsquarter. It and stand up after cultivation, is a member of the amaranth unless conditions are perfect.

Figure 3-11. Redroot pigweed, Amaranthus retroflexus.

Management of Weeds

Mechanical Controls Sunflowers can stand up well to a variety of types of mechanical cultivation. Producers in Vermont will often cultivate two or three times with rela- Figure 3-9. Serious weed pressure can decrease yields and make har- tively low crop loss. Cultivation vesting sunflowers very difficult. 23 with a tineweeder can be a successful method for weed control in sunflowers, both pre- and post-emergence (Figure 3- 12). Trials conducted in VT in- dicate that cultivation with a rear-mounted tineweeder at both 6 (pre emergence) and 12 (post emergence) days after planting can provide weed control similar in effectiveness to herbicide (Figure 3-13; Ta- ble 3-3, page 25). Timing of tineweeding is very important to achieve maximum weed control. The best time to tin- Figure 3-12. Rear-mounted tineweeder. eweed is when the weeds are in the white thread stage and ing, and row crop cultivators limited, and are essentially re- have yet to emerge. Once the remove weeds between rows stricted to pre-plant incorpo- weeds have emerged and be- very efficiently. Because herbi- rated herbicides that have rel- come established removal with cide options to control broad- atively short periods of activity a tineweeder becomes more leaf weeds after sunflower has in the soil. As mentioned earli- difficult. At this stage the tin- been planted are limited, most er there are also herbicide tol- eweeding must become more producers rely heavily on culti- erant varieties (Clearfield; Ex- aggressive and as a result can vation after sunflower emer- pressSun) that can also be used also lead to crop loss. Higher gence. In organic systems, to assist with postemergence seeding rates should be used if strong rotations and cover broadleaf weed control. Herbi- mechanical cultivation is used crops become equally im- cide options for annual and for weed control in sunflowers. portant elements of the weed perennial grass weeds are fair- (Table 3-3, page 25). control strategy. ly extensive (Table 3-4, page 25). However, care must be Standard cultivation equipment Chemical Controls taken to ensure that these are such as row crop cultivators or Because sunflower is a broad- registered for use in sunflow- spring-toothed harrows are leaf crop, herbicide options for ers and will not cause damage highly successful at eliminating broadleaf weed control are to the crop. Most of the herbi- weeds between rows, but in- row weeds can remain problematic after using these imple- ments. Generally, two cultivations before the sunflowers reach V-6 or V-8 is sufficient to eliminate weeds for the rest of the season. Often cover crops are seeded at the time of final cultivation. Seeding a cover crop at this stage will not inter- rupt sunflower growth. Canopy closure occurs around V-10, after which pressure from newly establishing weeds is nearly non-existent.

Tineweeding is extremely effective at eliminating weeds when they are just germinat- Figure 3-13. Effects of tineweeding and chemical controls on weed populations, 2010 data, UVM Extension. 24

Table 3-3. Effectiveness of tineweeding and its timing on population and found in the label and contact yield (DAP = days after planting), 2011. your local Extension agency or Harvest Weed herbicide dealer for more in- Weed Treatment Population Sunflower Yield Biomass formation. (lbs/ (bu/ (plants/acre) ac) ac) (lbs/ac) Sunflower Bird Pests Tineweeded 6 DAP 20,700 2,176 77.7 1,133 Tineweeded 12 DAP 20,400 2,108 75.3 1,218 Birds are a highly problematic Tineweeded 6 & 12 DAP 18,800 2,075 74.1 505 pest in all sunflower systems. Control 21,900 2,170 77.5 1,821 They are mobile, they can eat Herbicide 22,900 2,482 88.6 594 huge amounts of seed, and Mean 20,990 2,200 78.6 1,050 they typically travel in large flocks that can collectively cides that are registered for many have strict guidelines cause serious devastation use in sunflowers should be about incorporation. Always (Figure 3-14, page 26). In Ver- applied pre-planting, and closely follow the directions mont, birds are especially de-

Table 3-4. Herbicides registered for use in sunflowers in Vermont, 2013. Check with your local Extension agent or State Agency of Ag for up-to-date information on pesticide use. Sunflower Growth Tradename Active Ingredient EPA registration numbers Weed group control stage applied Pre-plant, pre- Germinating annual grasses Micro-Tech Alachlor 524-344 emerge and broadleafs Newly established grass & Aim EC Carfentrazone-ethyl 279-3241 Pre-plant broadleaf; non-selective Clethodim Clethodim 42750-72-72693 Any Growing annual & perennial Pre-plant (spring or Germinating annual grasses & Sonalan HFP Ethalfluralin 62719-188 fall) some broadleaves Roundup Original Pre-plant, pre- MAX, Roundup Glyphosate (Potassium 524-445, 524-549, 524-537, 100 Established grass & broad- emerge, pre-harvest PowerMAX, Round- Salt) -1121 leaf; non-selective desiccant up WeatherMAX, Pre-plant, pre- Duramax/Durango Glyphosate Diethyla- Established grass & broad- 62719-556 emerge, pre-harvest DMA mine Salt leaf; non-selective desiccant Durango, Glypho- Pre-plant, pre- max Plus, Honcho Glyphosate Isopropyla- 62719-517, 62719-322, 524-454, Established grass & broad- emerge, pre-harvest Plus, Glyphosate 41 mine Salt 42750-61-72693 leaf; non-selective desiccant Plus Imazamox Ammonium Beyond* 241-379 Post-emergence Broadleaf weeds* Salt* Pre-plant, pre- Gramoxone, Established grass & broad- Paraquat Dichloride 100-1217, 74530-32 emerge, pre-harvest Helmquat 3SL leaf; non-selective desiccant Prowl H20, Prowl Germinating annual grasses & Pendimethalin 241-418, 241-337 Pre-plant (fall) 3.3 EC some broadleafs Established annual & perenni- Assure II Quizalofop p-Ethyl 352-541 Any al grasses Pre-harvest desic- Sharpen Saflufenacil 7969-278 Established broadleafs cant Poast Sethoxydim 7969-58 Any Annual grasses Dual Magnum/ Pre-plant, pre- Germinating annual grasses & S-Metolachlor 100-816 Medal EC emerge some broadleaf Pre-plant (fall or Small seeded broadleaf and Spartan 4F Sulfentrazone 279-3220 spring) sedges Trust, Treflan TR- Germinating annual grasses & 10, Dintec Treflan Trifluralin 1381-146, 62719-131, 68156-4 Pre-plant some broadleafs 4D * Only for use in Clearfield sunflowers 25

American goldfinches are late Red-winged blackbirds gener- breeders, generally nesting in ally begin their fall migration late June and early July. During in late October and November this time, they feed on seeds – in northern Vermont, migra- almost exclusively, usually of tions begin at the earlier end of plants in the sunflower family that range, while in southern (e.g. thistles) and of alder, Vermont, flocks form around birch and elm trees. Though the first of November. Occa- they are mostly year-round sionally, large flocks (mostly of residents and do not migrate, males) will form during the fi- concentrated flocks of imma- nal two weeks of August, and ture and adult goldfinches move short distances south be- form in late September and fore beginning the bulk of their early October (once the migration with the rest of the breeding season is over) in population. Males double fat search of food for winter fat reserves shortly before begin- reserves. ning migration. Figure 3-14. Bird damage reduces yield drastically in Ver- mont sunflower crops. Red-winged Blackbirds Management of Birds The glossy black color and structive because our small bright red and yellow shoulder Because flocks of goldfinches fields, typically bordered by patches of male red-winged and red-winged blackbirds are hedgerows, provide the per- blackbirds are hard to mistake. typically at their peak activity fect food with nearby shelter They are arguably the most just as sunflower seeds reach from predators (Figure 3-15). common bird in North Ameri- maturity, but while the plants On a field scale, physical pro- ca, and are also one of the most are still too wet for harvest, the tection such as netting is not visible. They commonly sit on birds can do significant dam- generally feasible, and there- high perches in fields, on tele- age. Taking the sunflowers out fore deterrents are the best phone wires, and anywhere of the field before the birds option. Cannons, squawk box- else that they can be noticed become problematic is not es, scarecrows, eye-spot bal- easily. practical, since combines gen- loons and shiny ribbons can be erally cannot remove seed effective for short periods of time. However, birds will become accustomed to each of these tactics fairly quickly; they need to be moved regularly and used in combinations in order to stay unpredictable to the birds.

American Goldfinches American goldfinches are common birds in our area in fields, hedgerows and at bird feeders. During the spring and summer, male goldfinches are bright yellow, except for their black foreheads and black wings with white markings. Fe- males are slightly drabber in coloration, with an olive hue on Figure 3-15. Average bird damage in Vermont, as compared to other their upper body. sunflower-producing regions, 2009-2012 (Kandel, 2012).

26 from the sunflower head until it has dried down significantly. There are a few strategies to protect the crop from birds while the sunflowers dry down.

Cultural Controls Scare tactics can be effective, but only with heavy management (Figure 3-16). Goldfinch- es and blackbirds are both highly intelligent, and become accustomed to scare tactics quickly. Scarecrows, eye-spot balloons and shiny ribbons need to be moved around the Figure 3-16. Some farmers deter birds with “scary eye” balloons sus- field on a daily or every other pended above fields; nets are only feasible on small plots. day basis. Cannons and squawk boxes need to go off at random intervals, and should size of the flock. An extra few of June tend to have less bird also be moved around the field acres, therefore, can accom- damage than sunflowers plant- to different spots on a regular modate that loss. ed in mid-May. More research basis. While these tactics will Lastly, preliminary evidence needs to be conducted to bet- not eliminate crop losses to suggests that planting dates ter understand the relationship birds, they can reduce losses can be manipulated to avoid between planting date and by shortening the time birds bird populations. Planting bird damage in sunflowers. feed in the field. Unfortunately, dates pushed into the first part quantifying the gain from such devices is difficult.

A second strategy is to select varieties that have large and flat enough heads to fully bend over as the plant dries. It is much easier for birds to feed on sunflower heads that are still standing vertical, because they are able to perch easily and access the entire head. As the head becomes horizontal and parallel to the ground (face down) the birds only have access to the very edge of the head (Figure 3-17). This trait, though controlled genetically, is not currently selected for in varieties.

Some producers have also opt- ed to deal with the amount of crop that a bird flock eats by planting additional acres of sunflowers. A bird flock of a certain size can only eat an Figure 3-17. Head morphology can minimize bird damage. Large, droop- amount proportionate to the ing sunflower heads are more difficult for most birds to access. 27

4. HARVESTING PRACTICES

Timing the harvest correctly is sue is not sticking to the seed essential not only to getting the anymore. To test this, flex the most seed possible, but also to seed head; the seeds should getting the highest quality appear somewhat loose, but seed and oil from the crop. not so loose that they fall out Seed harvested before the immediately. Waiting too long head is dry will cause the wet will lead to shattering during tissue to clog up the combine, harvest and hence yield losses. the seed will not thresh out of Additionally, overly dry seed the head easily, and the trash will often break and be de- will not separate well from the hulled in the combine, increas- Figure 4-2. Modified combine in seed. Harvested too late, the ing the likelihood that it will action, Alburgh, VT, 2012. seed will break in the com- blow out the back with the bine, have poor oil content, lighter trash (stems, chaff, and not yield as well. Adjusting weeds and other unwanted signed to catch sunflower and checking the performance plant material). heads as they break from the of the combine is as critical as stalk and fall between rows or calibrating the planter – with- Harvesting Equipment to the sides. While this attach- out carefully adjusted equipment can be quite expensive, ment, the losses from shatter- Combines with row crop heads the designs can be replicated ing and seed blowing out the are often used to harvest sun- fairly easily and inexpensively back of the combine quickly flowers. Row crop headers on the farm (Figure 4-1). eat into yields. work well, however, because the chains that hold onto the Because sunflower seeds are Plant Maturity & Seed sunflower stalks can keep the large, light, and fairly delicate Moisture Content plant moving toward the cutter compared to many other crops, bar and thresher. Grain heads cylinder and fan settings In general, sunflower seeds do not work well because sun- should be much lower than need to be somewhere below flowers plants stand much with most other crops, and con- 20% moisture in order to har- higher than grains and can fall cave settings should be more vest with a combine. The limit- over and be lost on the ground. open. As seed moisture in- ing factor is not the seed itself However, modifications can be creases, concave settings as much as it is the sunflower made to a grain heads to har- should be closed slightly, and head. In order for the combine vest sunflower. One major cylinder speeds increased. Re- to be able to break apart the adaption are catch pans. Sun- view the equipment manual’s head and thresh the seed easi- flower pans are produced by recommended settings and ly, the head needs to be dry many combine manufacturers. make the adjustments at har- enough that the receptacle tis- Sunflower-catch pans, are de- vest, and continue to tweak and adjust as needed depending on the particular conditions of the crop (Figure 4-2).

Figure 4-1. Left: homemade sunflower pans for a Case 660 combine (design by Roger Rainville, Borderview Research Farm); right: corn silage harvest head modified for harvesting sunflowers. 28

5. SEED PROCESSING AND STORAGE

Seed Cleaning

Cleaning seed before storage is critical to maintaining the quality of the seed and oil over the long term. Trash in the combined seed is mostly made up of the wet, dead florets still attached to the seed and green weed seed and residue. This wet trash can cause the seed to heat as it begins to rot or fer- ment in storage. Heated seed decreases oil yield and oil quality. Trash is also a source of moisture that can contribute to condensation in the storage bin and lead again to rot and mold. In addition, trash in the seed at the time of pressing can cause unnecessary wear on the oilseed press. The sunflower harvest can also contain the small black fungal bodies of sclerotia, which are difficult Figure 5-1. A stationary Clipper fanning mill can be used to clean the to separate from seed due to sunflower harvest. similar shape and weight.

Post-harvest seed cleaning is any other small grain will It is best to dry sunflowers with often necessary, and usually work. The target moisture for natural air powered by a blow- requires running the collected seed storage is between 9% er, in a bin designed specifi- seed through a rotary cleaner and 12% – the drier end of the cally for storage and drying. or fanning mill (Figure 5-1). range is better for seed stored Sunflowers should never be into the winter, while the wet- dried with air heated by open Seed Drying ter end of the spectrum is ade- flame or exposed heat coils, for quate for shorter-term storage risk of fire. Small fibrous hairs If the sunflower crop is harvest- (on the order of weeks). on the sunflower husk often rub ed above 12% moisture, the off and can ignite in the heat seed must be dried to bring the moisture down to a point Table 5-1. Drying times for several seed moistures and airflow rates where it can be stored without with 47°F air at 65% relative humidity, typical for the Northeast. unnecessary risk of spoilage Initial Seed Moisture Airflow Rate (cfm/bu) Drying Time and reduced oil content. Meas- ure the percentage of moisture 17% 1.0 648 hours (27 days) in the crop with a moisture me- 15% 1.0 480 hours (20 days) ter. Grain bins with perforated 0.75 720 hours (30 days) drying floors intended for oth- 0.5 960 hours (40 days) er small grain crops are suitable for sunflower – its large, 13% 1.0 336 hours (14 days) oddly-shaped seed means that 0.75 504 hours (21 days) a floor designed for essentially 0.5 672 hours (28 days)

Don’t risk a fire! Avoid open flame and exposed heating coils when drying sunflower seed!

Figure 5-2. A screw-in auger is perfect for drying one-ton batches. source, and then travel back to below 6% moisture loses oil the highly flammable seed. content very quickly and can The required drying time var- plug up the press, requiring ies with initial seed moisture, constant maintenance. air temperature and relative humidity, and the volume of air Seed Storage moving through the seed (Table 5-1, page 29). Once the sunflower seed has gone into the grain bin for stor- Small dryers that can be age, producers should perform placed in bulk bags with the weekly checks for seed heat- seed can dry relatively small ing and for condensation on batches of seed (a ton or less). the bin walls and ceiling until These auger-like aerators are the crop has cooled to below often physically screwed into a freezing (Figure 5-3). If any one-ton tote bags of seed to changes in humidity or temper- aerate the batch (Figure 5-2). ature occur within the bin, the With these dryers (and with seed should be cooled with an larger dryers), special care aerator immediately until the must be taken to not over-dry bin has regained its normal the seed before pressing. Seed condition. Once the bin and the seed have reached mid-winter temperatures, reducing checks to once per month is adequate.

Figure 5-3. Grain bin interior. Check on seed regularly during long-term storage. 30

Though only the major stages will be discussed in detail, Table 6-1 (page 32) details all of the subdivisions of the growing stages.

Growth stage 0 occurs between germination and emergence. In our area, emergence generally occurs within 7 days in warm conditions, but can take as long as 14 days in cooler conditions. As the cotyledons unfold (stage 1), and true leaves unfold (stage 2), the plant begins to form a rosette of true leaves. The taproot begins to elongate at this point as well. For winter canola, the development of a strong rosette in the fall is important, since the plant will go dormant once the CANOLA soil freezes. The next spring, plants will resume growth and develop new leaves from the Brassica napus , brassica rapa, brassica juncea crown of the plant. Energy stored in the overwintering root will be used to jump start early spring growth. Once the rosette is well- established, a flower cluster de- 6. GROWTH AND DEVELOPMENT velops at the top of the main stem, which then begins to elongate. Germination Requirements both winter and summer annu- als, both of which have shown The plant bolts as the flower de- Canola, or oilseed rape some success here in Vermont. velops, and by the time the plant (Brassica napus), is a tap-rooted All canola varieties are very nears its maximum height, the member of the mustard family cold tolerant, and germinate flower buds at the bottom of the and like its relatives, is fast well in soil temperatures as low flower cluster begin to open growing and competes favora- as 38°F. This allows spring crops (Figure 6-1, page 32). As flower- bly with other plants. In addition to be planted in mid- to late- ing progresses to the top of the to the Argentine variety that is April. Winter canola crops cluster, flowers at the bottom the most common (Brassica na- should be planted early enough drop away and the seed pods pus), some agricultural varieties to allow significant vegetative elongate. Once flowering has of Polish canola (Brassica rapa and root growth to reduce win- completed for the whole plant, syn. campestris) exist, as well as terkill; for Northwestern Ver- the pods at the bottom have usu- an Argentine canola-quality mont, mid-August is usually suf- ally begun to visibly fill with mustard (Brassica juncea), ficient. seed (stage 5), which change though both are rarely commer- from green to yellow to brown as cially available in the US. How- Growth Stages they mature. Oftentimes, stages 4 ever, research is underway in and 5 occur simultaneously, so Canada to develop Polish cano- Growth stages of canola are di- that some seeds may be mature la varieties that yield as well as vided into six major stages (0- while others are still green. Argentine canola and provide 5), all of which can be divided other agronomic benefits. Ar- further for more specificity gentine canola has been bred as (denoted with a second digit). 31

Table 6-1. Canola growth stages in detail (Canola Council of Canada, 2011). Growth Stage Description 0 Pre-emergence / Germination The seed absorbs water and germinates, breaking the soil surface 4-10 days after planting 1 Seedling The cotyledons unfold, but no true leaves develop 2.1 Rosette The first true leaf expands 2.2 Rosette The second true leaf expands 2.3, etc. Rosette More true leaves expand, without the stem elongating significantly. The rosette stage typically lasts through 8-10 leaves forming before stem elongation begins 3.1 Bolting A flower cluster is visible in the center of the rosette 3.2 Bolting The stem begins to elongate (bolt), as more of the flower cluster becomes visible 3.3 Bolting The lower buds of the flower cluster become yellow 4.1 Flowering Flowers at the bottom of the cluster open 4.2 Flowering Most flowers open; bottom pods begin to elongate, with no indication of seed fill 4.3 Flowering All flowers are open; the bottom pods begin to fill with seed 4.4 Flowering All flowering completes; seeds in the bottom pods begin to enlarge 5.1 Ripening Seeds in lower pods full size, translucent 5.2 Ripening Seeds in lower pods mostly green 5.3 Ripening Seeds in lower pods green-brown or green-yellow 5.4 Ripening Seeds in lower pods yellow and brown 5.5 Ripening Seeds in lower pods fully brown, plant mostly dead

Pollination honeybees are strongly attract- pollen from plant to plant. If ed to canola, and will contrib- Polish varieties become more All Argentine canola varieties ute to pollination (Figure 6-2), common in the US, it will be are highly self-compatible and page 33). Polish varieties (B. important to understand the require no pollinator activity to rapa) are not self-compatible, different pollination require- achieve high yields. However, and require pollinators to carry ments and effects on the crop.

Figure 6-1. Canola growth stages. 32

7. CROP ESTABLISHMENT & PRODUCTION

The process of establishing a field, while the remaining nu- good stand of canola requires trients are generally returned careful attention to seed bed to the field. preparation, planting date, and fertility and pest management. Nitrogen should be applied This section describes best pre-planting due to the high production practices for canola sensitivity of canola seed to salt in the Northeast. and ammonia injury. N availa- Figure 6-2. Pollinators are at- tracted to canola’s bright yellow bility of 90-125 pounds per flowers. Soils and Fertility acre will allow a yield potential in the range of 2000-3000 lbs Canola does well in a wide va- per acre, assuming other field Maturation and Senescence riety of soil conditions, though conditions are favorable and it excels in loamy soils with production practices are done After all of the seeds in the good internal drainage and a properly. pods have turned brown, the pH in the 6.0-7.0 range. Yield plant begins to die and dry losses begin to occur in soils For spring canola, field specif- down (Figure 6-3). As the plant with pH 5.5 and lower; symp- ic N recommendations are giv- tissue dries, the pods become toms of low pH include cupped en by multiplying the yield highly susceptible to shatter- leaves early in the develop- goal (lbs/ac) by 0.05, then sub- ing, which can cause the pods ment of true leaves. Canola tracting the available nitrate N to split and result in seed loss. does not perform well in soils and the previous crop credit. Timing harvest to capture the that are saturated, especially An example follows: maximum number of mature when they do not drain quick- seeds while avoiding losses to ly. Hardpan soil layers that re- For a yield goal of 2000 shattering requires regular duce subsurface drainage or lbs per acre on a field scouting in the field to deter- surface compaction that holds following hay, with 15 mine when the crop is ready. water on top of the soil can easily drown canola plants. Emer- lbs per acre of available gence can be significantly re- N from the soil: duced if heavy rains cause soil crusting after planting; canola 2000 x 0.05 - 15 (soil N) - seedlings are particularly inef- 40 (hay credit) = 45 lbs N fective at breaking through per acre to be applied hard soil crusts. In excessively drained, dry soils, drought stress can be problematic, as Care should be taken to not canola is also intolerant of wa- over-apply nitrogen, as canola ter stress. is very prone to lodging as a result of over-fertilization. Ap- Nutrient Application plying the correct amount (i.e. Canola has nutrient require- addressing only the crop ments that are similar to most need) of nitrogen is more criti- small grains, with the excep- cal in winter canola than in tion that canola requires much spring canola because both too more sulfur (Table 7-1, page much and too little N will inhib- 34). These data provide esti- it winter survival; too little N mates of whole plant and seed does not allow enough vegeta- crop nutrient uptake require- tive growth before winter, and Figure 6-3. Seed pods fill and begin ments. Nutrients contained in too much encourages leggy to ripen in spring canola. the seed are removed from the plants that are more sensitive 33

Table 7-1. Nutrient uptake values cant yield boosts can occur that can perform within the for whole plant and for seed crop from sulfur additions. Soils with length of the growing season. (Canola Council of Canada, 2011). test values lower than 10 ppm Canola’s rapid maturation Whole Removal sulfur should receive addition- makes it an ideal oilseed can- plant in seed al sulfur in the form of either didate for colder regions of uptake ammonium sulfate or degrada- Vermont where fall-seeded (lbs/ac) (lbs/ac) ble elemental sulfur at rates of small grains or cover crops fol- Nitrogen 93.0 55.0 20 – 40 lbs per acre. low the canola crop. (N) Phosphorus 14.0 10.0 Though winter canola varieties (P) are not generally rated for ma- Potassium 76.0 14.0 Variety Selection turity, it is important to choose (K) varieties that perform well in Sulfur 23.0 7.0 Similar to other oilseeds, most (S) canola is grown in the Great the fall and that have good win- Boron 0.16 0.04 Plains and central Canada. Va- ter hardiness. Most seed com- (B) rieties that perform well there panies rate winter hardiness as do not necessarily perform part of the evaluation of the va- to frost damage. Fall nitrate well in the Northeast. Even riety. For the most current tests are important for correct- within Vermont, different evaluations of variety perfor- ly addressing winter canola N amounts of snowfall and dates mance in Vermont, contact demand. A general rule of of spring thaw from year to UVM Extension. thumb calls for one-third of the year will produce significant total N needed for the crop to differences in how varieties In spring canola variety trials be applied in the fall before perform (Figure 7-1). The in Vermont, most varieties planting winter canola, with the guidelines below are meant to were fairly consistent in their remainder to follow in the aid growers in selecting varie- time requirement for develop- spring. ties, but growers’ own experi- ment. Generally, 1100-1500 ence should be followed over GDD units are required to Phosphorus and K recommen- these guidelines. reach maturity, but because dations should be determined the plant dries down quickly, through a standard soil test. harvest can occur very soon Canola is an excellent scaven- Maturity afterward. ger of P and generally 20 to 30 The first major element of se- lbs per acre applied as starter lecting canola varieties for pro- Yield Potential fertilizer can meet the needs of duction is to choose varieties Most canola varieties (both the crop. If soil test P levels are low additional P fertilizer may be required. Potassium fertiliz- 2500 2011 ers can also be added to the 2000 starter but special care must ) 1 2012 be taken to make sure N + K - 1500 rates do not exceed an approximate 10 lbs per acre. Canola 1000 seed is especially susceptible to fertilizer salts and hence, 500 high levels of N and K fertilizers can cause detriment to the 0 emerging seeding. moisture (lbs ac

Seed yield 8% atharvest The major difference between small grains and canola nutrient demand is in sulfur re- Variety quirements. Canola has a much higher sulfur demand than Figure 7-1. Seed yields from selected winter canola varieties, 2011-2012 most other crops, and signifi- data, UVM Extension. 34

devastating to a canola crop. 700 2011 Choosing varieties that have 600 2012 some resistance to common fungal diseases can improve

500

) 1

- yields, especially here in the 400 Northeast where fungal diseas- 300 es are common. Canola varieties are often rated on their re- 200 sistance to Blackleg as com- 100 pared to a “check variety” that

is highly susceptible to the dis- moisture (lbs ac 0 ease (Table 7-2).

Oilyield at7.5% pressing Herbicide Tolerance Like disease resistance, herbi- Variety cide tolerant varieties can be useful tools for farmers. Varie- Figure 7-2. Oil yields from selected winter canola varieties, 2011- ties that are resistant to Round- 2012 data, UVM Extension. up (glyphosate) and Liberty (glufosinate) herbicides have winter and spring) have slight- High rates of N application re- been developed through ge- ly higher yield potential as duce oil content in the seed, netic engineering technology. compared with other oilseeds though the likely increases in Clearfield canola varieties such as sunflowers. Yields in seed yield may outweigh the were developed through tradi- Vermont have been variable in reduction of oil content. Seed tional breeding (i.e. non-GMO) the past, but range between moisture below 6% can reduce and offers resistance to the 1300 and 3000 lbs per acre, oil content as well; pressing herbicide Beyond (imazamox). with a mean of about 1900 lbs over-dried seed has resulted in Some Clearfield canola grow- per acre depending on nitro- oil contents as low as 20% in ers have reported that seed gen fertilization, seeding rates UVM Extension pressing trials. losses at harvest can introduce and pest damage. Some varie- There is a great deal of varia- a heavy weed population that ties have occasionally yielded bility in oil yield from varietal is difficult to control later in the as much as 4000 lbs per acre, differences in oil content, as rotation with other Clearfield and while such high yields are well as year-to-year differ- crops (e.g. Clearfield canola rare and difficult to achieve, ences (Figure 7-2). volunteers are difficult to con- they reflect what yields are trol in Clearfield sunflowers). possible under ideal condi- Disease Resistance tions. Winter canola has yield- Disease resistances bred into Hybrid vs. Open-Pollinated ed slightly better in our region, canola have been helpful to Many varieties of canola are primarily due to lack of disease growers in lowering the pres- hybrids, but there are also a and pest pressure. sure from significant diseases large number of open- such as Blackleg, which can be pollinated (OP) varieties, and Oil Content & Quality In general, oil contents of 40%- 42% are expected and often Table 7-2. Blackleg resistance ratings, with incidence ranges. reported for most canola varie- Rating Code Incidence of Infection* ties across the country, though canola oil contents in UVM Ex- Highly Susceptible HS 90%-100% tension trials typically average Susceptible S 70%-89% 30-35%. However, several factors control oil content during Moderately Susceptible MS 50%-69% and after the growing season, Moderately Resistant MR 30%-49% including variety, soil moisture, soil N availability, and Resistant R 0%-29% seed moisture at pressing. * As compared to Westar, a highly susceptible variety 35

Find out more! Annual research reports available at: www.uvm.edu/extension/cropsoil/research growers should take into ac- balanced with the need to count this difference when or- leave the soil structure coarse dering seed. Hybrid seeds are enough to prevent surface the product of two distantly- crusting. related parent lines which create offspring that are typically To plant canola, grain drills very robust and produce high should be set to plant at a yields. When these hybrids depth of 0.5—1.0”, which helps reproduce, however, they do to provide even emergence. not produce similar offspring – Planting as deep as 1.5” is only instead the next generation of- suitable for large-seeded vari- ten has many stems or branch- eties, which usually include es, produces few flowers, and hybrid varieties; otherwise, is generally not as vigorous. emergence will be poor and Therefore, growers cannot weed pressure high. Trials save seed from hybrid crops conducted in northwestern (e.g. corn, soy, sunflower) for Vermont showed that the high- the next year’s planting. Figure 7-3. Canola row with est yields result from seeding emerging seedlings. rates between 6 and 9 pounds In open-pollinated varieties, per acre, though no significant closely related parental lines yield increase occurs from are crossed to produce off- Planting Practices seeding rates higher than 6 spring similar to the parental pounds per acre. Therefore, to lines. Though open-pollinated Canola can produce similar save seed costs, lower rates varieties often yield slightly yields across a variety of plant should be used. In addition to lower than hybrid varieties, populations by adapting the higher cost of planting at high- this has not been consistently number of flowers, pods and er rates, lodging and disease true for UVM Extension trials. seeds per pod. However, en- transmission are more likely In less than ideal conditions, suring a good, even stand of and can be more rapid, lead- open-pollinated varieties can canola is also important for re- ing eventually to reduced yield sometimes yield better than ducing lodging and for control- (Figure 7-4, page 37). hybrids because of their ability ling weed pressure and dis- to tolerate a wider variety of ease (Figure 7-3). Data from field trials in north- conditions. The fact that open- western Vermont have also pollinated varieties produce Seedbed Preparation & Seeding shown that row spacing from 6 plants similar to the adults al- Methods to 18” produce similar yields. lows farmers to save seed from Because of canola’s small seed Individual canola plants re- year to year, which can virtual- size, it requires a fairly shallow spond to differences in plant ly eliminate seed costs. Over planting depth with good soil density by adjusting the the long term, open-pollinated to seed contact, which in turn amount of branching and the crops have the ability to adapt requires a smooth and level number of flowers per branch. to the microclimate of the farm seedbed. Because of this need, Depending on the planting and as natural outcrossing between canola has not traditionally harvesting equipment availa- individual canola plants in the worked well in reduced-tillage ble, UVM Extension recom- field occurs. situations, especially no-till, mends planting in 6-inch rows where residue and an uneven to help control weed pressure It is important to remember soil surface generally leads to and promote even plant spac- that varieties with specialty uneven emergence. Canola ing across the field. Wider traits often require the grower benefits most from an even rows may be used especially if to sign a trait agreement. seedbed that has been lightly white mold issues are preva- packed, though this must be lent. Wider rows may help with 36 more airflow in the field.

Seeding Dates Spring canola should be planted as early as the fields can support tillage and planting equipment. Because germination occurs once soils have reached 38° F, canola could be planted as early as mid-April, but often early May is more feasible. Planting spring canola early also allows an earlier harvest, which is helpful to producers because it spreads out workload and equipment availability in the fall, and allows for the establishment of a cover crop or a winter cereal grain. Because heat and humidity during the flowering period can be detrimental for pollination and seed set, spring cano- Figure 7-5. Winter canola planted on varying dates (left to right: 15- la should be planted no later Aug, 23-Aug, 29-Aug, and 6-Sep). Photographed 24-Sep 2012. than mid-May.

Winter canola should be plant- date trials, only plots planted ed early enough in the fall that before September 1 were har- it can establish a strong rosette vestable. before the first killing frost, when it will become dormant. Usually, this requires that it be planted before September (Figure 7-5). In UVM Exten- sion’s winter canola planting

Figure 7-4. Effect of seeding rate on spring canola seed yields, 2008 data, UVM Extension. 37

8. PEST MANAGEMENT

Though oilseed canola crops Flea Beetles are fairly new to the region, Phyllotreta cruciferae, Phyllotreta striolata other Brassica crops are very well established and the pests Identification & Signs of Damage that are problematic for those Flea beetles are small beetles that get their name from the fast hops are also problematic for cano- that they take when disturbed, similar to fleas. They are common pests la. In particular, several weeds in spring and winter canola, feeding heavily on early leaf tissue, which and fungal diseases warrant is when they cause careful management, and there the most damage are a large number of insects (Figure 8-1). Dam- that could be challenging to aged seedlings can control depending on the other be set back signifi- crops in the rotation. Birds cantly in their devel- have become the most severe opment and are often pest for our trials, consistently noticeably lacey or causing the greatest harvest holey in appearance. loss. Winter canola is less susceptible than There are benefits and costs spring canola to flea associated with each pest man- beetle damage be- agement strategy, and growers cause the plants Figure 8-1. Flea beetle on canola seedlings. must decide for each situation grow out of their which tool presents the best most susceptible stage prior to beetle emergence. chance of eliminating or reducing a particular pest problem Lifecycle at the lowest cost. In most cas- Flea beetles overwinter as adults in the leaf litter and dead grasses of es, preventative control hedgerows between fields. They emerge in early May when tempera- measures are cheaper and tures average about 50°F, feeding on young emerging plant tissue, in- more effective, but require cluding crops. Females lay eggs in the soil, which hatch in a week or more planning, typically in the two. The larvae continue to feed on plant tissue until fully grown. They form of rotation cycles and tim- then pupate in the soil for 11 to 13 days before emerging as the new ing field practices correctly. generation of adults.

Table 8-1. Insecticides registered for use on canola crops in Vermont, 2013. Check with your local Extension agent or State Agency of Agriculture for up-to-date information on pesticide use. Labeled for use against: Common trade Active ingredient EPA registration numbers name Flea beetles Lepidopteran larvae*

Brigade 2EC, Bri- Bifenthrin Ammonium 279-3313, 279-3108 Yes AM, CW, WW, L, OL gade WSB Sulfate

Bifenthrin zeta- Hero, Hero EW 279-3315, 279-3329 Yes AW, CW, OL Cypermethrin Warrior with Zeon Technology, Warri- lambda-Cyhalothrin 100-1112, 100-1295 Yes AW, CW, L, OL or II with Zeon Technology Cruiser 5FS Thiamethoxam 100-941 Yes WW Mustang MAX EC, zeta-Cypermethrin 279-3327, 279-3380 Yes AW, CW, L, OL Steed * Lepidopteran larvae includes: armyworms (AW), cutworms (CW), wireworms (WW) loopers (L), & other caterpillars (OL) 38

canola, fungal diseases in canola crops do not appear to be as extensive and well- established as they are in sunflower. However, rather than viewing this lack of disease as breathing room, it should be viewed as an opportunity to maintain good cropping practices that will keep disease away.

Blackleg

Identification & Signs of Dam- age Blackleg is characterized by tan or brown lesions that develop first on the leaves and then develop on the stems as Figure 8-2. Blackleg infection on spring canola leaf. similar lesions ringed in black tissue (Figure 8-2). Small black birds. Planting a “trap crop” Major Insect Pests fruiting bodies eventually ap- around the field edge has been pear on the exterior of the There is only one main insect effective for smaller areas, or dead tissue. Stem infections pest in canola production in the where the trap is more desira- are most common during the northeast, and has contributed ble than the protected crop. rosette stage and early bolting to complete crop failure in stages of canola’s develop- some seasons. Flea beetles Chemical Controls ment, and occur typically just have been detrimental to cano- In Vermont, applying insecti- below a leaf attachment. Stem la growers, and fields should cides is not common after the lesions eventually girdle the be scouted regularly for the plants are established, if at all. stem and then can cause col- insect. However, several insects, in- lapse and often lodging. cluding flea beetles, can cause

serious damage to young Management of Insects Lifecycle plants. There are several con- The Blackleg fungus overwin- ventional insecticides that are Cultural Controls ters on plant residue infected registered for flea beetle con- Early planting of canola may the previous growing season. trol in canola (Table 8-1). Or- help reduce flea beetle dam- During the following spring, ganic insecticides are also age in spring canola. Early the fungus produces fruiting available. Each state has differ- planting will allow canola bodies that discharge spores, ent regulations and require- plants to develop past the infecting the next season’s ments regarding pesticides, so seedling stage prior to flea crop. However, these fruiting it is best to contact your Uni- beetle emergence in mid to bodies release their maximum versity Extension service or late May. Larger plants may number of spores in the sec- pesticide dealer to find out withstand flea beetle damage ond year, and will continue to more. and allow the plant to continue release spores until the plant developing without insecticidal residue has been fully degrad- sprays. Delaying the planting Canola Disease Pests ed by the fungus. date of canola crops until after the overwintering beetles have Though the climate in Vermont Once environmental conditions emerged is also a strategy, is ideal for fungal pathogens, reach an optimum for Blackleg though such a delay could push especially in crops that are infection (wet plant tissue, be- harvest back into September, seeded in narrow rows and tween 60° and 75°F), the causing more of an issue with have dense vegetation like spores begin to infect the plant 39 tissue. Any previous damage to the plant tissue aids in the infection, as these breaks in the plant tissue act as entry sites for the fungus. The infected plant tissue becomes residue that remains in the field, and supplies new spores for the next generation cycle.

Sclerotinia (White) Molds

Identification & Signs of Dam- age In canola, Sclerotinia infects the stems as a stem rot. The disease develops late in the season, usually after flowering has ended. Early signs of infection Figure 8-3. Sclerotinia causes deformed growth. are brown lesions on the stem that eventually give way to than in dry seasons. Once the soil health and crop yield is a white mold with black sclerotia plant is fully infected, the scle- well-planned rotation that uti- (small fruiting bodies) as the rotia cause the stem to col- lizes alternating broadleaves plant dries down. Stem infec- lapse, dropping the fruiting and grasses and longer peri- tions often cause the plant to bodies into the soil; otherwise ods of fallow or mixed-species die, sometimes prematurely, they are scattered during har- hay. Rotations are especially and to eventually lodge. In vest. important for canola because heavily infested fields, lodging of its susceptibility to both can occur in large patches as Sclerotinia and Blackleg, two falling plants put more pres- Management of Disease fungal diseases that are capa- sure on already weak stems. ble of high levels of crop dam- Cultural Controls age. Sclerotinia, also discussed Lifecycle Choosing disease-resistant hy- in the sunflower section of this Sclerotinia overwinters as scle- brids is one way to mitigate the manual, is a wide-ranging fun- rotia that can lie dormant in the incidence of disease in canola gal disease that infects over soil for as many as six years. crops. For example, due to the 350 species of host plants, both They resemble small rocks or development of Blackleg- cultivated and wild. Blackleg is clods of soil and camouflage resistant hybrid varieties, the similar, though the number of very well. Each spring, some of incidence of this disease is fair- host plants is far smaller. How- the sclerotia in the soil release ly low in Vermont. Reports of ever, the lifecycles of both dis- spores due to moisture or tem- severe infestations are essen- eases have periods of dorman- perature cues, some release tially non-existent in canola. cy in fruiting bodies that can spores when the roots of host However, even for varieties last up to four years (Blackleg) plants come in contact with that have a rating of and up to six years them, and others continue to lie “Resistant,” there can still be (Sclerotinia). Because canola is dormant. These spores float up low levels of infestation that slightly less susceptible to to the canopy where they land take away yield potential. Sclerotinia than sunflower and on dead or decaying plant tis- Therefore, even with the use of Blackleg populations are not sue (usually dead flower pet- resistant hybrids, it is still im- well established in most fields als), and grow to infect the portant to practice good rota- yet, successive canola crops stem tissue (Figure 8-3). Rainy tions. should be planted no more and humid conditions in the fall than every 3 years in any field, seem to be prime conditions Like most other crops, the most with non-susceptible crops in for Sclerotinia, because infec- effective tool for combating the intervening time. tion rates are higher in wet falls pest issues while maintaining 40

Table 8-2. Registered fungicides for use in Vermont for canola, 2013. Check with your local Extension agent or State Agency of Ag for up-to-date information on pesticide use.

Controls: Common trade EPA registration Active ingredient name numbers Black Leg Sclerotinia Alternaria Blight

Dynasty, Quadris Azoxystrobin 100-1159, 100-1098 Yes (seed-borne) No Yes Endura Boscalid 7969-197 No Yes No

Fosphite Phosphorus Salts 68573-2 No No No

Sclerotinia is well established seedlings. Most fungicides ap- planting will help the canola in Vermont, though canola ap- proved for use in canola in establish and grow rapidly pri- pears to be slightly less sus- Vermont are best used as part or to the germination of most ceptible than other crops, most of a regular spray program, annual broad leaves. The best likely because it is generally which makes them very expen- conventional weed control harvested around the same sive to use, and probably not strategies involve pre-plant time the conditions are becom- worth the cost. Table 8-2 pro- herbicides. Organic strategies ing wetter and more conducive vides a list of registered fungi- rely on good rotations that re- to Sclerotinia infections. Elimi- cides that can be used in Ver- duce weed pressure in the ear- nating the disease from a heav- mont for canola crops. ly spring. ily infested field can be very difficult, but sticking to good Biological Controls There are two particularly rotations that only reintroduce Contans®, an organic-certified problematic broadleaf weeds canola into a field every third biological agent (fungus) that that share many physiological year will help keep new fields attacks the dormant bodies of qualities with canola and there- disease-free and fungal popu- Sclerotinia in the soil, is also a fore thrive in fields of that crop. lations in old fields under con- highly effective means of re- Management of these weeds is trol. ducing Sclerotinia build-up in treated collectively because of the soil. Contans® has been their similarity in growth habit. Wider row spacing can reduce reported to be very effective at pressure from fungal diseases reducing incidence of Sclero- Lambsquarters by promoting airflow around tinia white molds to near zero This familiar weed is character- the base of the plant, but also within two years, though it is ized by its alternate, triangular- encourages more weeds to not a substitute for well- shaped leaves, its pale green sprout. Spacing rows from 6 to planned rotations. flowers that grow from junc- 9” seems to provide a good tions between the main stem balance of weed control and Canola Weed Pests and branches, the striped ap- airflow to reduce fungal pressure. Fortunately for growers, canola is highly competitive with Chemical Controls weeds, often smothering out The use of fungicide-treated even the toughest competition. seeds is widespread and suc- However, broadleaf weeds can cessful for preventing fungal be very difficult to control be- diseases in the seedling stage, tween canola emergence and though many of the more seri- canopy closure, because ous fungal pathogens emerge standard broadleaf herbicide later in the lifecycle of the options typically make a point plant. Most canola seed is of targeting the mustard family. treated with a combination of Fortunately, canola is fairly fungicides that target downy hardy and responds very fa- mildew, seedling dampening, vorably to tineweeding—once Figure 8-4. Common and other diseases that plague it is well established. Early lambsquarters. 41 pearance of the main stem it- used to cultivate between self, and its tall, coarse growth rows. However, there are nar- habit (Figure 8-4, page 41). It is row-row cultivators, such as an annual weed that is quick to those made by the Schmotzer sprout on bare soil, and is company from Germany, therefore common in almost which make cultivating in these any broadleaf crop. It grows situations possible. very quickly, topping out at 4’ or more by the end of the In addition, tineweeding once growing season. It produces the crop is established can be thousands of seeds per year somewhat effective in control- that are viable for long periods ling weeds. Tineweeding just of time in the soil. after planting can be risky as Figure 8-5. Redroot pigweed. the shallow planting depth of Redroot Pigweed the seed can easily be dis- This weed is commonplace in competitor in earlier stages – turbed by the tines on the im- both broadleaf and grass narrower rows provide a more plement. This can lead to seeds crops, and is similar in appear- even plant density across the being carried to the surface of ance to lambsquarters (Figure field, which establishes a good the ground and result in poor 8-5). It is a member of the ama- canopy more quickly, but also and spotty germination. ranth family, and like most of creates more shade at ground its relatives, it produces huge level. While this even shade is Chemical Controls numbers of small seeds that beneficial for weed control, it Canola is a broad leaf crop and sprout easily. It is a deep- also creates humid conditions hence most herbicides availa- rooting annual with a robust at the soil surface, encouraging ble to control weeds in this stem that survives cultivation, the establishment of soil-borne crop are targeted towards especially if conditions are diseases such as Sclerotinia grasses (Table 8-3, page 43). slightly wet. It is best to hit this and Blackleg. Spacing rows Several varieties of herbicide plant early, before the roots from 6-9” seems to provide a resistant canola plants have have had time to establish. good balance of weed control made chemical control of weed and airflow to reduce fungal pests much easier. The Clear- Grasses pressure. field trait, which confers re- In conventional canola sys- sistance to Beyond tems, grasses are not particu- Mechanical Controls (imazamox), is the only herbi- larly problematic because cide resistance trait that is non- there are so many useful herbi- Tineweeding is extremely ef- GM. Roundup Ready and Lib- cide options. However, in or- fective at eliminating weeds erty Link canola varieties do ganic systems perennial rhi- when they are just germinat- exist and provide another zomatous grasses such as ing, and row crop cultivators means to weed control. quackgrass can cause serious are very effective at removing yield declines because they weeds between rows. Because Canola Bird Pests are not controlled well by culti- herbicide options to control vation, and can easily smother broadleaf weeds after canola Birds are a highly problematic young canola plants. has been planted are limited, pest in all oilseed systems. producers may want to rely on They are mobile, can eat huge Management of Weeds cultivation after emergence of amounts of seed, and typically the crop. In organic systems, travel in large flocks that col- Cultural Controls strong rotations and cover lectively can cause serious Managing row spacing is also crops become equally im- devastation. In Vermont, birds an important tool in controlling portant elements of the weed are especially destructive be- weeds and other pests. Canola control strategy. cause our small fields, typically is highly successful in competi- bordered by hedgerows, pro- tion with weeds once it reaches Because canola is planted in vide the perfect food with near- the rosette and bolting stages. narrow rows, standard row cul- by shelter from predators. However, it is not a successful tivation equipment cannot be 42

Table 8-3. Herbicides registered for use in canola in Vermont, 2013. Check with your local Extension agent or State Agency of Agriculture for up-to-date information on pesticide use.

Common Active Canola EPA registration numbers Weed group control trade name ingredient growth stage

Aim EC Carfentrazone-ethyl 279-3241 Pre-plant Newly established grass and

Clethodim Clethodim 42750-72-72693 Any Growing annual and perennial

Stinger Clopyralid Mo- 62719-73 Post- Some broadleaf weeds, including Pre-plant, pre- emergence, Established grass and broadleaf; Reglone Diquat Bibromide 100-1061 pre-harvest non-selective desiccant Sonalan HFP Ethalfluralin 62719-188 Pre-plant Germinating annual grasses and Traxion/ Touchdown Total, Roundup Pre-plant, pre- Original MAX, Glyphosate 100-1169, 524-445, 524-549, emergence, Established grass and broadleaf; Roundup (Potassium Salt) 524-537 pre-harvest non-selective PowerMAX, desiccant Roundup WeatherMAX Pre-plant, pre- Duramax/ Glyphosate Diethyla- emergence, Established grass and broadleaf; 62719-556 Durango DMA mine Salt pre-harvest non-selective desiccant Durango/ Glyphomax XRT, Glypho- Pre-plant, pre- 62719-517, 62719-322, 524- max Plus, Hon- Glyphosate Isopropyl- emergence, Established grass and broadleaf; 445, 524-454, 42750-61- cho, Honcho amine Salt pre-harvest non-selective 72693, 74530-4 Plus, Glypho- desiccant sate 41 Plus, Helosate Plus Imazamox Ammonium Post- Beyond* 241-379 Broadleaf weeds* Salt* emergence Assure II Quizalofop p-Ethyl 352-541 Any Established annual and perennial Poast Sethoxydim 7969-58 Any Annual grasses Trust, Treflan 1381-146, 62719-131, 68156 Germinating annual grasses and TR-10, Dintec Trifluralin Pre-plant -4 some broadleafs Treflan 4D * Only for use in Clearfield canola American goldfinches are com- American goldfinches are late time), and make small slits in mon birds in our area in fields, breeders, generally nesting in the pod through which they eat hedgerows and at bird feed- late June and early July. During the seeds. Because canola ers. During the spring and this time, they feed on seeds stems are not strong enough to summer, male goldfinches are almost exclusively, usually of support them well, they often bright yellow, except for their plants in the sunflower family knock plants over, causing black foreheads and black (e.g. thistles), but are not hesi- shattering of the pods that they wings with white markings. Fe- tant to eat canola. They com- do not eat. Though they are males are more muted in their monly perch in the flower clus- mostly year-round residents coloration, with olive hues on ter as the bottom pods are rip- and do not migrate, concen- the upper parts of their bodies. ening (well before harvest trated flocks of immature and 43

es, scarecrows, eye-spot balloons, and shiny ribbons can be effective for short periods of time. However, birds will become accustomed to each of these tactics fairly quickly, and so they need to be moved regularly and used in combinations in order to stay unpredictable to the birds.

Figure 8-6. Bird damage in well-formed canola seedpods.

adult goldfinches form in late the crop earlier than a direct September and early October cut combine harvest. – once the breeding season is over – in search of food for On a field scale, physical pro- winter fat reserves. tection such as netting is often not feasible, and can be insuffi- Growers in the Northeast have cient if not perfectly impene- also reported detrimental trable (Figure 8-7). Therefore, flocks of red-winged black- deterrents may be the best op- birds, mourning doves, spar- tion. Air cannons, squawk box- rows, and other seed-loving birds (Figure 8-6).

Management of Birds

Cultural Controls Adjusting planting and harvest dates can reduce pressure from particular pests by offset- ting the lifecycle of the plant so that it is out of sync with the lifecycle (or infestation cycle) of a pest. For example, planting canola early may allow it to be harvested before the annual fall bird migration, thus reducing the amount of the crop that is eaten by birds. Harvesting canola crops earlier is possible, especially if desiccants or Figure 8-7. A sparrow (foreground) and a finch (background) perch on swathing are used to terminate canola netting, feeding on accessible seedpods. 44

9. HARVESTING PRACTICES

Knowing when to harvest cano- propriate if the seed is mature la can be one of the biggest enough (~10% moisture). In challenges to growing this other regions, swathing can crop. It has a notoriously small reduce losses from early frosts. harvesting window to maxim- However, in the Northeast, due ize yield and quality – harvest to the likelihood that rain too early and not all of the seed could damage the crop while it may be mature, which causes is in the windrow, swathing is heating and sweating in the not a common practice. Direct bin, while a late harvest leads cutting is far more common, to shattering and heavy crop despite the fact that harvesting loss. This section provides process losses can be high. some tips on when and how to Penn State University reports Figure 9-1. Harvesting winter harvest to maximize yield and that seed losses during harvest canola with a small combine. oil quality. can be as high as 35-40% of yield (Karsten, 2012). plants are often intertwined Plant Maturity and sometimes pushed over, & Moisture Content Harvesting Equipment so it is important to set the cutter bar at an appropriate Canola is ready to harvest Canola is harvested in a very height to get all of the pods when the seed reaches an av- similar fashion to a small cereal while reducing the quantity of erage of 8-10% moisture grain, using a grain head with a stem material that gets pro- (several measurements are reel to pull in the plant (Figure cessed. Getting out of the com- needed because seeds from 9-1). By harvest time, canola bine to check that the crop is the bottom of the canola plant will be more mature than those Direct Combining Swathing followed by Combining at the top). Once the canola is this dry, however, the plant Shorter harvest window – can only Wider harvest window – can occur itself is so dry that the pods occur below 15% seed moisture, but anytime after seed reaches 30% typically shatter on contact, typically above 8% seed moisture and direct combining (also called direct cutting) can result Harvest losses from shattering can Little to no field losses from in large crop losses. Harvest- range 10%-50% if harvest is late shattering ing earlier to avoid losses from shattering may mean that not Weed seeds mature and are harvested along with the canola – especially all of the seed is mature, and Incorporates fewer weed seeds canola seeds will not mature detrimental for OP varieties that get further once they’re harvested, saved and planted again leading to lower oil content. Crop is safer from bad weather Crop can be damaged by a heavy Harvest can occur either by the events other than high wind rain between swathing and harvest more conventional direct cut- Best yields and oil content if the crop ting, or by swathing and letting is allowed to mature while standing Swathed canola crops have lower the seed finish maturing in a in the field (assuming no shattering at yield and oil content than direct cut windrow and then combining harvest) once the seed is fully mature. Requires more tractor time, and Each method has its ad- Less equipment need (time and special swathing and pickup vantages and disadvantages, special attachments) and producers should deter- attachments mine which will work best in Less effective for tall, tight crops – More effective for tall crops with their current production sys- higher danger of bunching and intertwined stems tem. Direct combining is ap- twisting the windrow 45

getting pulled in well is im- look for other places that seed portant to ensuring high yields, is running out of the bin. Can- especially where the standabil- ola’s small size and smooth, ity of the crop varies from field round shape enables it to flow to field or within a field. freely, often finding holes that are not obvious or even possi- If swathing the crop, a swather ble to see without the help of is important to make good the seed. windrows that lay nicely on the stubble. To reduce the amount of soil and to also reduce loss 10. SEED PROCESSING & STORAGE during combining, keep the stubble between 5 and 7” so Seed Cleaning they can be cut to fit effectively that the windrow stays off the in the bin. Similar to other ground. This height also lowers Clean seed is critical for long grains, concrete flooring in the likelihood of disease term storage, especially for storage or drying bins is not spreading through the crop small-seeded crops like cano- recommended, because seed during the dry down period. If la. The small size allows the on the bottom will absorb combining large acreages of seeds to pack tightly, restrict- moisture, and eventually mold swathed canola, a windrow ing airflow and encouraging and spoil. Additionally, like the pickup head is helpful to get fermentation of wet trash in the combine, any holes or seams in the crop into the head nicely seed. The first step to clean the seed bin will leak seed, and to avoid losses below the seed is to select the correct and should be sealed before combine. screens for the combine. If the the seed is put into the bin if seed is not clean enough after possible. Combine settings should re- one pass through the combine, flect the fact that canola thresh- passing it through a high vol- Drying canola to long-term es very easily – excessive ume seed cleaner can remove storage moisture is best done grinding of the stems is not the necessary amount of trash with unheated air (less than 15° necessary and could increase (Figure 10-1). If trash compris- F above ambient), since exces- the seed moisture. The con- es more than about 3% of the sive heating reduces protein cave settings should be harvested seed bulk, problems quality and leads to sharp de- opened to 3/4” in the front and such as hot spots, mold, and clines in oil quality. Small dry- between 1/8” and 1/4” in the insect activity can erupt in the rear. Keep the clearances as storage bin. high as possible without losing full pods. The cylinder speeds Seed Drying should be fairly slow, because canola seed can crack easily. Some modifications to normal Fan speeds can be set similarly grain dryers may be required to other small grains, but it is to accommodate canola be- better in general to separate cause of its small size. A se- the seed from the chaff by cured layer of burlap or muslin shaking it through the screens over a standard larger-grain rather than blowing the chaff floor can provide a simple, low out. -cost alternative to buying a canola-specific seed-drying One common source of harvest floor, though the edges of the loss for many producers is bin can still present leakage seed running out of holes in the issues if the fabric isn’t secured combine. It is important to seal well. Canola-specific floors for any obvious holes before har- grain bins are not too expen- vest with caulking or duct tape. sive and are easy to install— Figure 10-1. A fanning mill like Once there is seed in the bin it they are generally available in this could be set up indoors or can be helpful to get out and long and wide sections so that outdoors. 46 ers that can be placed in bulk bags with the seed are also adequate for drying relatively small batches of seed (a ton or less). These auger-like aerators are often physically screwed into a one-ton tote of seed to aerate the batch (Figure 5-2, page 30). If heating is necessary, keeping temperatures below 110°F will help avoid over-drying, which would greatly reduce oil content. Airflow rates of 0.75 – 1.0 cfm/bu are the most cost- effective settings because of the relatively high airflow resistance that canola provides due to its small size.

Long-Term Storage

Once the seed has reached 8% moisture, it is ready for long- term storage. During the first month of storage, canola often Figure 10-2. One-ton totes, or bulk bags, as shown here at Borderview undergoes a “sweating” period, Research Farm, are often used to transport and store seed. which is exacerbated at high moisture contents and high temperatures. During warm days, moisture will accumulate at the center of the seed, close to the floor, as warm, moist air cools and falls through the seed, re- leasing moisture as it settles. On cool days moisture will accumulate at the peak of the storage bin, as the airflow patterns re- verse. It is critical to look for moisture to determine whether aeration is necessary. Maintain- ing good aeration and frequent monitoring is critical to ensuring high seed quality. Dried seed can be stored in a multi- tude of containers, but should be monitored and/or moved often (Figure 10-2).

ADDITIONAL RESOURCES

Berglund, D., editor. 2007. Sunflower production. North Dakota State University Extension Service, Fargo, ND. Canola Council of Canada. 2011. Canola growers manual [Online]. Available at http://www.canolacouncil.org/crop- production/canola-grower%27s-manual-contents/ (verified 22 Jan. 2013). Kandel, H. 2013. 2012 National Sunflower Association Survey. 2013 National Sunflower Association Research Forum, Fargo, ND. 9-10 Jan. 2013. National Sunflower Association. Karsten, H. 2012. Penn State University. Canola research update 2011. 2012 Annual Oilseed Producers Meeting, White River Jct, VT. 26 Mar. 2012. University of Vermont Extension. National Sunflower Association. 2012. Growers [Online]. Available at http://www.sunflowernsa.com/growers/ (verified 22 Jan. 2013). Smith, J. 2011. Sunflower planter recommendations [PDF online]. Available at http://panhandle.unl.edu/c/ document_library/get_file?uuid=417f49d4-6495-4d0d-ab5e-1a826071b8b7&groupId=131817&.pdf (verified 22 Jan. 2013). The Greenbook Group. 2012. Chemical database solution [Online]. Available at http://www.greenbook.net/ (verified 22 Jan. 2013). Vermont Agency of Agriculture. 2013. Pesticide programs: product registration. Available at https:// usaplants.vermont.gov/ProductRegFSA/BrandSearch.aspx (verified 22 Jan. 2013).

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