A guide to EM 9040 • October 2011 RIPARIAN TREE AND SHRUB PLANTING in the Willamette Valley: Steps to Success Brad Withrow-Robinson, Max Bennett, and Glenn Ahrens Contents Step 1. Plan Your Project...... 2 Know your watershed...... 2 Know your site...... 2 Restore functions, not just vegetation...... 3 Consider passive restoration...... 3 Identify obstacles...... 4 Design your project...... 4 Step 2. Select and Obtain Plant Materials...... 4 Species selection...... 4 Local plant materials...... 7 Planting stock...... 8 Step 3. Prepare the Site...... 11 Seedling survival and growth...... 11 Competing vegetation...... 12 Mechanical control...... 12 Chemical control...... 14 Minimizing erosion...... 14 Figure 1. Newly installed planting along Newton creek, Benton County, Oregon. Step 4. Plant Your Trees Right...... 16 Photo by Donna Schmitz, Benton Soil and Water Conservation District. When to plant...... 16 Seedling care and handling...... 16 Planting tools and techniques...... 16 lanting trees and shrubs to restore Particular challenges in the Willamette Spacing and arrangement...... 17 streamside areas, enhance fish and Valley include summers that are Step 5. Take Care of the Planting...... 18 Pwildlife habitat, improve water hotter and drier than in the adjacent Maintenance weed control...... 18 quality, and achieve other environmen- Coast Range and Cascades foothills Animal damage control...... 19 tal benefits is increasingly common in and streams that run through highly Irrigation...... 20 Oregon (figure 1). But the success of modified agricultural and urban areas Step 6. Monitor and Learn from riparian plantings varies widely, and (figure 2). some fail outright (see “Survey shows Results...... 21 This guide describes six steps to help Recordkeeping and evaluation...... 21 variable success with riparian tree planting,” page 2). landowners, watershed council mem- Appendix A. Key Riparian Functions, bers, agency personnel, and others Supporting Vegetative Conditions, Establishing a riparian planting is not communicate about, plan, and imple- and Riparian Buffer Design easy. Seedling survival and growth ment successful riparian tree and shrub Considerations...... 22 are often poor. Competition from plantings in the Willamette Valley: Appendix B. Promoting Natural weeds can be high. Animal damage 1. Plan your project. Regeneration...... 23 is common. Soil texture on a site can Appendix C. Project Design Features vary from coarse sand to dense clay. 2. Select and obtain plant materials. Planting sites may flood frequently and Considerations...... 24 3. Prepare the site. in winter yet become very dry each 4. Plant your trees right. Appendix D. Sample Monitoring summer. Management tools such 5. Take care of the planting. Questions, Objectives, and as irrigation, machinery, and herbi- Techniques...... 26 cides may be regulated or restricted. 6. Monitor and learn from results. For More Information...... 27 Additional Resources...... 27

Brad Withrow-Robinson, Extension forester, Marion, Polk, and Yamhill counties; Max Bennett, Extension forester, Jackson and Josephine counties; and Glenn Ahrens, Extension forester, Clatsop County; all of Oregon State University, Forestry and Natural Resources Extension Program. STEP 1. PLAN Know your site Once you understand watershed YOUR PROJECT conditions and needs, examine your site. Identify specific challenges (e.g., Know your watershed frequent flooding [figure 3], poorly Your project goals should reflect drained soils, abundance and type of conditions and needs in your local weeds, or likely animal damage) that watershed. Identify what is missing might be serious constraints to a suc- or most in need of enhancement, and cessful planting. set priorities accordingly. In western Next, determine what could be Oregon, for example, warm stream enhanced at your site to contribute temperature is commonly identified to overall watershed health. Consider as the primary water-quality issue, so things you might try to change (e.g., providing shade to maintain cool water amount of shade, bank stability, or conditions is often a priority. livestock use near the stream). Some Begin planning by reviewing water- changes might be easy; others might shed assessments from your local be difficult or expensive. Some actions watershed council or larger public or will have almost immediate benefits; private landowners in your watershed improvements from other actions won’t be evident for years or decades. Figure 2. Willamette Valley ecoregion. (find your local watershed council at http://www.oregon.gov/OWEB/ Make sure any difficult and expensive Image from The Oregon Conservation Strategy. 2006. WSHEDS/wsheds_councils_list.shtml). actions line up with your priorities. Salem, OR: Oregon Department of Fish and Wildlife. Many watershed councils have already Reproduced by permission. Be sure to consult others. Identify part- identified key constraints and opportu- ners in conservation organizations or nities in watersheds or subbasins (e.g., other agencies who might be able to elevated stream temperatures or lack of Survey shows variable help identify needs and opportunities large wood). success with riparian at your site (figure 4). tree planting Slightly fewer than half of 105 ripar- ian tree-planting projects in western Oregon achieved tree survival rates Checklist for Step 1: Plan your project of 75% or more, according to a 2002 Time and thought at this stage will lead to a better, more cost-effective project study by the Oregon Watershed in the long run. Enhancement Board. ☐☐ Assess needs for the riparian area in the context of watershed conditions In 40% of the projects in the study, and priorities. What is missing or most in need of enhancement? fewer than half the trees survived. ☐☐ Observe site conditions to determine what actions will address identified Projects installed under the needs and have the greatest potential for success. Conservation Reserve Enhancement ☐☐ Set goals based on what will help restore key functions in the future Program were more successful rather than what is thought to have prevailed in the past. than projects funded by grants. The ☐☐ Consider promoting natural regeneration of trees and shrubs and other study’s authors attributed this dif- passive restoration approaches as well as planting. Try to get the greatest ference to the greater use of site value for your investment. preparation, postplanting mainte- ☐☐ Think about possible obstacles, such as a mismatch between project size nance, and tree protection under and budget, equipment availability, and your time, skills, and commit- the program. ment. Is there a good chance of success? Source: Anderson, M., and ☐☐ Develop a site-specific design that addresses local watershed issues, G. Graziano. 2002. Statewide is appropriate for site conditions, and can be accomplished with Survey of OWEB Riparian and available resources. Stream Enhancement Projects. Salem, OR: Oregon Watershed Enhancement Board.

2 Riparian Tree and Shrub Planting in the Willamette Valley Figure 3. Flooding of a young riparian planting on the North Yamhill Figure 4. Assess current site conditions to determine benefits already River, Yamhill County, Oregon. being provided, what is needed, and establishment challenges. Photo by Amie Loop-Frison, Yamhill Soil and Water Conservation District. Photo by Tara Davis, Calapooia Watershed Council.

Restore functions, not Surface ltering just vegetation Large, woody debris Conditions before European settle- Shade for stream ment are sometimes used as a guide for desirable riparian conditions. But restoration to presettlement conditions Subsurface is often difficult or inappropriate. Few ltering accurate or detailed records of those Litterfall conditions exist, and existing records are snapshots of single moments in Stream bank and time, with no assurance that they are channel stability representative of a longer time frame. Also, because riparian ecosystems are Sediment retention complex and change over time, there is Figure 5. Important functions of a riparian area include shade for the stream, stream bank no “natural” condition for a given area. stability, woody debris for the stream, sediment retention, litter for aquatic organisms in the stream, water filtering, aquatic habitat, and riparian wildlife habitat. Ecologists recommend restoring or enhancing important riparian func- tions (figure 5), not just vegetation temperatures, and drop leaves and actions, such as installing nesting conditions. For example, development insects into the stream. Plantings will boxes (for wood ducks and screech across the Willamette Valley has led to eventually provide large wood, which is owls) or platforms (for osprey). loss and degradation of many habitats, important for modifying stream chan- including once-extensive networks of nels and creating in-stream habitats. Consider passive riparian forests, prairies, and savan- nas. This, in turn, reduced plant and Riparian areas are also important ter- restoration animal populations. One functional restrial habitats. A well-developed Consider whether your site will be goal is to improve habitat by restoring shrub layer provides foraging and nest- able to grow and develop as you desire or enhancing conditions that are criti- ing sites for migratory songbirds. Large without actively planting it (a passive cal to survival of a species or group of trees are needed to provide nesting restoration approach). For example, species. See Appendix A (page 22) for or foraging sites for large birds, such you may be able to meet tree establish- more examples of riparian functions. as herons and pileated woodpeckers. ment goals by encouraging natural Large trees take time to develop, but regeneration of species already pres- Riparian vegetation provides many you may accelerate their growth by ent and reproducing on the site (see important functions for aquatic habi- planting fast-growing species, spacing Appendix B, page 23). Perhaps the only tats. For example, restoration projects them far apart, and controlling weeds action needed is to remove grazing designed to aid salmon populations and other competition. You can also livestock, weed competition, or inten- often focus on establishing tree spe- provide some functions normally pro- sive cultivation. cies that create shade, reduce stream vided by large trees through interim

Riparian Tree and Shrub Planting in the Willamette Valley 3 • What conflicts might arise with Identify obstacles adjacent land uses (e.g., farming Design your project It is important to assess operational or grazing), and how can these Although it is helpful to look at other constraints, identify problems, and be resolved? plans and projects, be sure to design a resolve conflicts during the planning • Is there good access to the plant- riparian planting that is specific to your phase. Think about and discuss the ing site, and can you move in any site, reflects identified goals, and can be following questions with advisors and needed equipment or supplies? accomplished with available resources. organizational partners: • Does the site location allow fre- Your design will need to address many • How much money, time, quent visits for monitoring and features: and energy are available for maintenance, or will you visit the this project? site only occasionally? • Width and position of the • Is the budget adequate for the • How will you determine planting size of the project? project success? What are • Species to plant and type of the consequences of an • Do you have a good understand- planting materials unsuccessful planting? ing of demands on resources • Plant spacing and arrangement to accomplish key activities The scale of the project is also an • Access for people and equip- throughout the project (from important consideration. Small proj- ment (for maintenance and planning, to planting, to weed ects (e.g., dozens to a few hundred monitoring) control and maintenance)? Can trees) allow use of a wider range of • Fencing or other protection from you realistically meet those techniques, such as hand-cutting livestock and wildlife demands in a timely way, consid- competing vegetation, that might ering your other commitments, be prohibitively expensive on larger You also need to decide how to prepare health, and access to and skill in projects. As the project’s size and the site for planting, how to protect using equipment and tools? If complexity increase, so does the need seedlings from weed competition, not, is there money in the budget for cost-effective methods of site and how to maintain the planting. to hire help? preparation, planting, and vegetation The following sections provide more control. Balance the scale of your proj- information on these topics. Also see ect with the budget, time, and other Appendix C (page 24) for additional resources available. project design considerations.

drought tolerance. Start by identify- STEP 2. SELECT ing native species growing on similar Checklist for Step 2: AND OBTAIN sites nearby. Select and obtain plant Conifers, such as Douglas-fir or west- PLANT MATERIALS ern redcedar, are often a priority for materials riparian plantings in mountainous Species, source, and stock type are Species selection areas because they provide dense shade important considerations. Your plant selections will affect the and durable, large wood. However, many conifers are not as well adapted ☐☐ Identify species that will pro- appearance and function of your ripar- ian planting for decades. Trees and to riparian areas in the Willamette vide the key riparian functions Valley that are flood prone or poorly you identified during planning. shrubs must be able to survive and prosper when planted and also provide drained and should be selected ☐☐ Choose species that are well the functions you need in the future. with caution. adapted to your site. Consider Tables 1 and 2 list characteristics of tolerance to shade, flooded or Tolerance to floods and poor native trees and shrubs. waterlogged soils, and drought. drainage ☐☐ Select locally adapted, geneti- Site adaptation Areas along the stream channel and cally diverse seedlings or other Choose species that are well adapted banks as well as sloughs and swales plant materials that fit your site to site conditions. Moisture—either may be subject to frequent or pro- conditions, management con- the lack or excess of—is often the most longed flooding. Species selected for straints, and budget. important factor in both planting suc- these areas must have high flood toler- ☐☐ Plan ahead. Order seedlings cess and long-term survival. Consider ance. Black cottonwood, bigleaf maple, and other types of planting how the local climate and soils affect western redcedar, red alder, white stock well in advance. moisture, and select species on the alder, and Oregon ash tolerate flooding basis of moisture needs and flood and (figure 6).

4 Riparian Tree and Shrub Planting in the Willamette Valley Table 1. Characteristics of riparian and bottomland tree species for the Willamette Valley. Tolerance to Species Flooding Drought Shade Comments Bigleaf maple Medium Medium High Medium-lived tree. Provides early season food for Acer macrophyllum seedeaters and good structural habitat. Black cottonwood High Low Low Large, fast-growing tree. Prefers moist, well-drained Populus trichocarpa soils. Well-suited for shade and bank stabilization. Popular nesting platform for some birds. Roots well from cuttings. Douglas-fir Low Medium Medium Tall, long-lived tree. Provides dense shade, durable Pseudotsuga menziesii dead wood, and structural elements. Does not tolerate flooding. Grand fir Medium Medium High Fast-growing tree. Source of woody debris. Abies grandis Oregon ash High Medium Medium to Slow-growing, medium-height tree. Tolerates poorly Fraxinus latifolia High drained, heavy clay soils. Older trees provide cavities. Oregon white oak High to High Low Slow-growing, medium-height tree. Tolerates poorly Quercus garryana Medium drained, heavy soils. Wood ducks and other wildlife eat its acorns. Ponderosa pine Medium High Low Large, long-lived tree. Moderate growth rate. Provides Pinus ponderosa durable dead wood and structural elements. Native Willamette Valley race is highly tolerant of both poorly drained and droughty soils. White alder High Low to Low Fast-growing, medium-height tree. The more common Alnus rhombifolia Medium alder in the Willamette Valley and other interior valleys. More tolerant than red alder of poorly drained soils and warm Valley climate. Nitrogen fixer. Red alder High Low Low Fast-growing, medium-height tree. Likes moisture, but Alnus rubra good drainage. Often struggles on poorly drained sites and in Willamette Valley climate. Nitrogen fixer. Western redcedar High Low High Likes moisture, but good drainage. Grows in Willamette Thuja plicata Valley riparian areas but may struggle. Premium source of large, woody debris.

A related but often separate problem is redcedar and red alder, may seem soil drainage. Soils on higher terraces appropriate but often grow poorly on in the Willamette Valley often have heavy (clayey) soils and in hot summer heavy, fine-textured (clayey) soils with conditions. Trees that do best under very poor drainage and poor aeration these conditions include Oregon ash, during the rainy season, regardless of Oregon white oak, white alder, black whether they flood regularly (table 3). cottonwood, and the native Willamette These are essentially wetland soils. Valley race of ponderosa pine. Shrubs Plants on these soils are subjected to that do well include Douglas spirea, saturated conditions for much longer snowberry, red-osier dogwood, periods than during surface flooding. and willow.

Poorly drained soils may be more Areas along natural river levies and limiting than floods for plant selec- higher edges of floodplains will also tion, and planting the wrong species flood, although less frequently and for on saturated sites is a common cause shorter durations. These sites may have Figure 6. Black cottonwood is well suited for of planting failure around the valley. well-drained soils and are suitable for giving shade and stabilizing stream banks. Plants associated with moist condi- a larger group of plants with medium Photo by Brad Withrow-Robinson, © Oregon State tions in the mountains, such as western flood tolerance. University.

Riparian Tree and Shrub Planting in the Willamette Valley 5 Table 2. Characteristics of riparian and bottomland shrub and small tree species for the Willamette Valley. Tolerance to Species Flooding Drought Shade Comments Cascara buckthorn Medium Medium Medium Small tree with cherry-like berries favored by Rhamnus purshiana many birds. Douglas hawthorn High Medium Medium to Small tree. Produces berries in late summer. Crataegus douglasii High Douglas spirea High Medium Low Low, dense shrub. Provides good cover. Spreading. Roots Spiraea douglasii well from cuttings. Elderberry, blue Medium Medium Medium to Large, vigorous shrub. Berries ripen in late summer. Sambucus caerulea High Elderberry, red High Medium High Medium shrub. Produces berries in early summer. Sambucus racemosa Mock orange Medium Medium Medium Tall understory shrub. Philadelphus lewisii Oregon crabapple High Medium Medium Large, thicket-forming shrub or small tree. Malus fusca Osoberry Low to Medium High Medium shrub. Blooms very early. Fruits ripen in Oemleria cerasiformis Medium late spring. Pacific ninebark Medium to Low Medium to Tall understory shrub. Roots from cuttings. Physocarpus capitatus High High Red-osier dogwood High Low Medium Tall understory shrub. Roots from cuttings. Cornus stolonifera Salmonberry High Medium High Common mountain riparian species sometimes seen in Rubus spectabilis Willamette Valley. Produces berries in late summer. Serviceberry Medium Medium Medium Large, thicket-forming shrub. Amelanchier alnifolia Snowberry Medium Medium High Low shrub. Roots from cuttings. Symphoricarpos albus Thimbleberry Low Low High Common mountain riparian species sometimes seen in Rubus parviflorus Willamette Valley. Produces berries in late summer. Vine maple Low Low High Common mountain riparian species sometimes seen in Acer circinatum Willamette Valley. Willow High Low Low Some willows are tree size; others are large shrubs. Root Salix spp. very well from cuttings. Well suited to bank stabilization and bioengineering projects.

6 Riparian Tree and Shrub Planting in the Willamette Valley Table 3. Common wetland soils of the Willamette Valley. Wetland (hydric) soils form when saturation, flooding, or ponding occur for long enough during the growing season that anaerobic conditions develop in the upper part of the soil. Anaerobic conditions are challenging for many species and often a limiting factor for tree and shrub growth.

This table shows Willamette Valley soils listed as hydric. There are other somewhat poorly drained to poorly drained soils (e.g., Amity silt loam) that, while not hydric, can limit species selection and growth of trees and shrubs. Name Landform Awbrig silty clay loam Terraces Bashaw clay Floodplains and terraces Brenner silt loam Floodplains and swales Concord silt loam Terraces Conser silty clay loam Terraces Courtney gravely silty clay loam Stream terraces Cove silty clay loam Floodplains Dayton silt loam Terraces Grande Ronde silty clay loam Terraces Huberly silty loam Swales and terraces Panther silty clay loam Low hills, slumps Verboort silty clay loam Floodplains Wapato silty clay loam Floodplains Waldo silty clay loam Floodplains Whiteson silt loam Floodplains Source: USDA Natural Resources Conservation Service; survey area version date: 12-23-2006. (http://www.or.nrcs.usda.gov/technical/soil/hydintro.html)

Drought tolerance Shade tolerance spacing and planting arrangements (see Appendix C, page 24), and selec- The Willamette Valley has hot, dry Fast-growing riparian tree species, tive thinning. summer weather, and moisture stress such as willow, cottonwood, and alder, is often a limiting factor in seedling quickly colonize disturbed areas after survival. Sites close to major rivers can floods. But these trees are intolerant Local plant materials actually be quite dry for new seedlings. of shade and not suitable for plant- Many species you select for your These riverbanks and levies often have ing in the understory of existing trees. planting likely grow in many loca- sandy or gravely soils with low nutri- Oregon ash, bigleaf maple, grand fir, tions in Oregon and North America. ent-and moisture-holding capacity, and western redcedar, and many shrub For instance, white alder is plentiful they dry out rapidly each summer once species are tolerant of shade and more in southwest Oregon, and ponderosa the rains stop. suitable for such areas (tables 1 and 2). pine is abundant in central Oregon. However, plants of the same spe- Although mature black cottonwood Shade tolerance also comes into play as cies from different environments can trees thrive along the sandy banks of young trees grow and begin to compete perform very differently on your site. the Willamette River, this species has with each other for light and other It is important to find seedlings and relatively low drought tolerance and resources. Slower-growing and smaller planting stock grown from Willamette may be difficult to establish on such tree species will tend to fall behind in Valley sources. Buying from a local sites until its roots reach moisture deep growth; if these species are not shade nursery is not necessarily enough; it is in the soil. In some situations, you tolerant, they will likely die and disap- where the seed (or other parent mate- can offset this issue with weed control pear from the stand. Such competition rial) comes from that counts, not the and irrigation. is part of a natural process but can lead place where seedlings are raised. to less diversity and a simpler stand structure than planned for or desired. See “Seed sources and genetic issues” Address this issue with thought- (page 10) for more information. ful species selection, appropriate

Riparian Tree and Shrub Planting in the Willamette Valley 7 Table 4. Characteristics of seedling and stock types for riparian plantings. Planting stock Size Several types of seedlings and stock (stem caliper types are used in riparian plantings Stock type and height) Unit cost range Comments (table 4). Consider these characteristics Bare root 0.1–0.5 caliper $0.15–$0.65 Wide availability. when selecting a stock type: 8–24 inches Winter planting. • Availability Roots vulnerable to drying. Requires • Handling sensitivity extra care in • Cost handling. • Ease of transport and planting Container plugs 0.05–0.3 caliper $0.25–$0.80 Fall to spring • Survival and growth potential 6–20 inches planting. Requires In general, bigger is better. Bigger less skill in handling. stock is less likely to be overtopped Easier for rocky sites. by competing vegetation and recovers Container: 1- to 0.2–2.0 caliper $1.00–$10.00 Fall to spring better when browsed. However, it is 5-gallon pots or 3- to 12–60 inches planting. Requires also more expensive to buy and plant. 4-inch by 18- to 24- less skill in handling. Ensure that bigger stock has an ade- inch PVC pipe Survives on droughty quate root system to support the large sites. Expensive shoot system. to plant. Bare-root seedlings (figure 7) are Cutting: cane or whip 0.25–1.0 caliper $0.20–$0.30 per Presoaking advised. grown in nursery beds, usually for 12–72 inches foot or labor and Can cut from local 2 years, and then dug and planted transport sites. Tolerates during the winter dormant season. flooding. Does They perform well if they receive not tolerate early proper care and are the foundation of weed competition. many riparian restoration projects. Grows rapidly. Cutting: pole 1.0–4.0 caliper Common designations for bare-root 48–96 inches seedlings: Ball and burlap 1.5–5.0 caliper $25.00–$250.00 Expensive. Instant • 2-0—2-year-old tree grown only (B&B) 36–240 inches landscape. in a nursery bed • 1-1—2-year-old tree grown 1 year in a nursery bed and 1 year in a lower-density transplant bed • Plug-1—bare-root seedling that started out as a small container seedling and was transplanted to an outdoor nursery bed and grown for 1 year

The 1-1s tend to be larger than 2-0s and have denser, more fibrous root systems. They also cost more. Plug-1 seedlings have characteristics of con- tainer and bare-root seedlings and well-developed, fibrous root systems. They are more expensive than other bare-root seedlings.

Advantages of bare-root seedlings:

Figure 7. Examples of different stock types. From left: Douglas-fir container plug, 2-0, 1-1, and • Low cost ponderosa pine plug-1. • Easy to transport Photos from Rose, R., and D.L. Haase. 2006. Guide to Reforestation in Oregon. Corvallis, OR: Oregon State University • Wide availability of many forest College of Forestry. Reproduced by permission. tree (and some shrub) species

8 Riparian Tree and Shrub Planting in the Willamette Valley Disadvantages of bare-root seedlings:

• Narrow planting window (winter dormant season) • Requires skill during planting • Greater sensitivity to improper handling and planting (e.g., root drying and other damage)

See Selecting and Buying Quality Seedlings, OSU Extension publication EC 1196 (http://extension.oregonstate. edu/catalog), for more information about stock types.

Container stock (figure 8) is grown in containers and planted with soil intact Figure 8. Large container stock at Stone Nursery, Central Point, Oregon. around the roots. Small container Photo by Max Bennett, © Oregon State University. seedlings commonly are referred to as plugs. Sizes range from “Styro-10s” (10 cubic inches of soil in the plug) to 1-gallon pots to large plugs grown in 24-inch-long PVC pipe.

Advantages of container stock:

• Longer planting window (fall through early spring) • Less skill needed during planting • Less potential for damage during handling and planting • Easier than bare-root seedlings to plant on rocky or otherwise dif- ficult sites (plugs) • Better survival on droughty sites (plugs) Figure 9. Cottonwood and willow cuttings, ready for planting. Note that the two cuttings in the foreground have begun to root. Disadvantages of container stock: Photo by Chris Van Schaack. • More difficult to transport to and around the site as size increases Advantages of cuttings: system held in place with a burlap • Potential for introducing weeds wrap. These tend to be much larger, • High cost • Relatively low cost much more expensive trees that are • Easy to plant generally inappropriate for most res- Cuttings (figure 9) are dormant sec- • Flood tolerance toration situations but may be used in tions of hardwood trees and shrubs. park settings and other green spaces in They have no leaves or roots. Large Disadvantages of cuttings: or near urban areas. cuttings are called whips, canes, or poles. Cuttings are used in the field • Greater vulnerability to dry Advantages of ball-and-burlap stock: and in nursery production of container conditions stock. When conditions are right, cut- • High sensitivity to weed competi- • Provide an “instant tree” tings root after planting; willow and tion during establishment • Good survival and growth cottonwood root better than other • Potential narrowing of genetic Disadvantages of ball-and-burlap species. Cuttings are available in sizes diversity (each rooted cutting is stock: from 1 to 10 feet long. For best results, a clone) generally select young (i.e., current- • High cost year and 1-year-old) wood and soak Ball-and-burlap (B&B) stock has cuttings before planting. a large ball of soil around the root • More difficult to plant than other stock types

Riparian Tree and Shrub Planting in the Willamette Valley 9 Many commercial forest nurseries in the Pacific Northwest grow plants suit- Seed sources and genetic issues able for riparian restoration projects. To ensure that plants are adapted to your site, select planting stock grown from The popularity of these projects, and a local seed source. How local is “local”? the demand for planting stock, has grown enormously in the past decade. Because climate varies so much over short distances in northwest Oregon, Most nurseries grow some stock on there is no rule of thumb (e.g., 50 miles) for how far trees and shrubs can be speculation (i.e., based on expected moved safely from their source. Instead, seed zones have been established to demand), which they sell on a first- minimize risk. come, first-served basis. These supplies don’t always meet demand, so order Seed zones are geographic areas with fairly uniform temperature, rainfall, early for the best availability of species, and other climatic factors. If the area includes major elevation changes, eleva- seed source, and stock type. tion bands within each zone further define areas with important similarities in conditions. You can also contract with nurseries to grow plants to your specifications. Trees can be planted safely within their zone of origin based on both the This gives you the greatest control of geographic seed zone and the elevation band. Planting in a higher or lower ele- seed source. A minimum number of vation band from the zone of origin increases the risk that the plant will adapt seedlings (e.g., 2,000) is required for poorly to its new environment. such contracts, and you will likely need Specify the seed zone and elevation (to the nearest 500 or 1,000 feet) when to start this process 2 years before your ordering seedlings. anticipated planting date. Seed zones have been established for most conifer species, red alder, and black Many local soil and water conserva- cottonwood. Relatively little is known about genetic variability among other tion districts and some chapters of the native riparian hardwoods and shrubs. In the absence of specific zones for Oregon Small Woodlands Association a species, use basic westside zones to guide seed transfer in other hardwood have annual plant sales, which are a and shrub species (figure 10). Seed transfer should be relatively safe within good place to purchase smaller num- these zones. In practice, planting stock is not always available from your bers of plants. Be sure to ask about desired seed zone and elevation. seed source. • Moving between two adjacent Use the following resources to find seed zones, especially close to nurseries that sell or specialize in their boundaries, may pose little native plants: risk, as long as there is relatively • Sources of Native Forest Nursery little difference in temperature and Seedlings (publication from precipitation. the Oregon Department of • Avoid moving seed across major Forestry): http://www.oregon. environmental divides, such as from gov/ODF/privateforests/docs/ the interior valleys to the coast and ForestNurserySeedlingSources.pdf vice versa. • Oregon Association of Nurseries: • Moving up in elevation (more than http://www.nurseryguide.com/ 1,000 feet) increases the risk of frost • Oregon State University damage. Moving down in elevation Extension forester poses less risk, although growth may • Oregon Department of Forestry be slower. stewardship forester • Regardless of zone boundaries, plants will be vulnerable to drought stress if seed is moved from areas of high precipitation (i.e., above 60 inches) to areas of low precipitation (i.e., below 30 inches). For more information, see Selecting Native Plant Materials for Restoration Figure 10. Basic seed zone map for Projects, OSU Extension publication western Oregon. Use for hardwoods and EM 8885 (http://extension.oregonstate. other species that do not have their own edu/catalog). designated seed zones. Image by Glenn Howe, © Oregon State University.

10 Riparian Tree and Shrub Planting in the Willamette Valley STEP 3. PREPARE Checklist for Step 3: Prepare the site THE SITE Weed competition is a serious obstacle to successful establishment of riparian plantings; it is usually easier to control competing vegetation before planting Streamside restoration sometimes than after. begins with a clean slate—an agricul- tural field free of established weeds, ☐☐ Anticipate future weed problems. Review your site assessment (Step 1, ready to plant. More often, the site has page 2) to identify weeds, barriers to effective planting, access issues, and well-established, invasive perennial management limitations. weeds, such as Himalayan blackberry, ☐☐ Allow enough time. It may take two or more seasons to get control of Scotch broom, and reed canarygrass some aggressive weed species. (figure 11), that must be controlled ☐☐ Choose site preparation methods that kill the root systems of perennial to allow good establishment of native weeds, such as blackberry and Scotch broom. Live roots will resprout. trees and shrubs. This control is gener- ally best done before planting, as part ☐☐ Consider effectiveness, duration, and cost. Herbicides are often the of site preparation. most effective and least costly method for controlling competing vegeta- tion. Tilling, cutting, mowing, pulling, grubbing, and mulching can also Good site preparation does not guar- be effective. antee long-term survival and growth, ☐☐ Plan ahead to minimize potential new problems. Aggressive site prepara- but it helps. Seedlings get off to a tion may remove competing weeds but also will expose bare soil, which better start, and future maintenance can lead to new (possibly worse) weeds and the risk of erosion. is easier. It is usually much easier and less expensive to control tough weeds Seedling survival and An effective approach to ensure good before planting than after. You may survival is to create a weed-free area need to spend two seasons getting your growth (3 feet by 3 feet or 4 feet by 4 feet) site ready for planting. Weeds compete with seedlings for for each seedling before planting and moisture and other critical resources. maintain that area for at least 2 years Some aggressive site preparation tech- Research has demonstrated that after planting (figure 12). Woodland niques are quite disruptive, can cause eliminating weeds from a relatively owners regularly achieve 80% to 90% unintended damage, and should be small area around the seedling can survival of bare-root seedlings planted used with caution after careful consid- dramatically improve seedling sur- in unirrigated, upland soils with eration of the situation. Select practices vival. Substantial improvements in this approach. appropriate to the problems and risks seedling growth, however, occur only at the site, keeping in mind that a min- The weed-free area can be spots, strips, when weeds are nearly completely or a broadcast treatment (the entire imalist approach to riparian planting eliminated. It is easier and cheaper to often leads to failure. field) depending on your objectives. achieve high seedling survival than Choose the target area and control rapid seedling growth. methods on the basis of site condi- tions and your preferences, skills, and equipment.

a b

Figure 11. Tall-growing reed canarygrass competes aggressively with transplanted Figure 12. Creating a weed-free strip (a) or patch (b) lessens moisture competition for newly seedlings. planted tree seedlings. Tree shelters protect seedlings from spray and browsing animals. Photo by Brad Withrow-Robinson, © Oregon State Photo 12a by Brad Withrow-Robinson, © Oregon State University. Photo 12b by Donna Schmitz, Benton Soil and Water University. Conservation District.

Riparian Tree and Shrub Planting in the Willamette Valley 11 Grasses are particularly competitive for of control methods is often required Competing vegetation several reasons: (figure 13). Table 5 describes site preparation methods for the two types of compet- • Grasses have a dense, fibrous See Managing Himalayan Blackberry in ing vegetation: herbaceous and woody. root system that rapidly absorbs Western Oregon Riparian Areas, OSU The most effective methods kill shoots soil moisture. Extension publication EM 8894 (http:// and roots of target weeds. Removing • Grasses start growing earlier extension.oregonstate.edu/catalog), for only the aboveground portion of in the season than most woody more information about controlling competing vegetation provides good vegetation and use available blackberry in riparian areas. access and temporarily reduces com- soil moisture by early summer. petition. However, if root systems are Seedlings need this moisture to Mechanical control not killed or removed, perennial weeds survive summer drought. Mowing is commonly used to clear will resprout and compete vigorously • Some grasses spread rapidly herbaceous plant debris and woody with planted seedlings. Future control via underground runners (rhi- species, such as blackberry, before will be more difficult. There is a clear zomes) and can resprout from planting. However, mowing alone is trade-off between less effective site root fragments. not an effective way to control peren- preparation and an increased need for • Dense herbaceous cover is good nial weeds, which simply regrow future maintenance. habitat for voles (meadow mice), after cutting. In some cases, multiple Weed control is a means to an end. which often kill seedlings by annual mowings over several years can Your goal is not to kill weeds, but to stripping their bark. substantially reduce blackberry cover allow seedlings to survive. and vigor. Tractor-mounted mowers Woody vegetation, such as Himalayan are preferred where access and slopes Herbaceous grasses and broadleaf blackberry and Scotch broom, com- permit, although soil compaction weeds compete vigorously with newly petes with seedlings for soil moisture might be a concern. Soil compaction planted trees and shrubs. Their effect and sunlight. These plants can remain has been shown to reduce seedling is strongest very close to the seedling highly competitive much longer than growth in upland forests. Where and in the first few years after planting. herbaceous plants. Suppressing these machinery use is not feasible, use aggressive, nonnative, weedy shrubs machetes, loppers, or brush cutters. A long enough for trees to establish chainsaw with a hedge-trimmer attach- can be a challenge. A combination ment is also effective.

a c

b

Figure 13. Example of Himalayan blackberry control in a riparian terrace next to a farm field: (a) just prior to mowing with a rotary mower, (b) in the middle of the first growing season, and (c) after 4 years of growth. Site preparation included two mowings followed by a fall application of glyphosate. Postplanting treatments included spot spraying with glyphosate and hand weeding. Photos by Max Bennett, © Oregon State University.

12 Riparian Tree and Shrub Planting in the Willamette Valley Table 5. Site preparation methods. Method Effectiveness and duration1 Cost/acre per application2 Comments Grasses and herbaceous vegetation Herbicides: applied with vehicle High $60–$200 Can apply to strips or planting spots. and boom spray or hose, or with 1–2 years Minimum area is 3 feet by 3 feet, backpack or hand sprayer centered on seedling. Dead plant material temporarily protects soil and delays weed reinvasion from seed. Mechanical: tilling High $100–$200 Weeds sprouting from seed rapidly reinvade 2–4 months exposed soil. Mechanical: mowing Low $50–$150 Mowing does not stop moisture 1–4 weeks competition but may reduce rodent problems. Must be repeated often. Manual: scalping, hoeing Medium $120–$360 Minimum area is 3 feet by 3 feet, centered 3–6 weeks on seedling. Weeds sprouting from seed rapidly reinvade exposed soil. Mulch (mats or other) Medium $150–$400 for mats Mats must be well secured and flat on 1–2 years ground. Minimum area is 3 feet by 3 feet, centered on seedling. Mulch mats can harbor rodents and might wash away in high water. Woody shrubs Herbicides: applied with vehicle High $60–$250 Complete spray coverage is most effective. and boom spray or hose, or with 1–3 years Dead plant material temporarily protects backpack or hand sprayer soil and delays weed reinvasion from seed. Herbicides: cut-stem or basal- High $50–$120 Apply water-soluble formulations to bark treatment 1–3 years cut stem surfaces. Apply oil-soluble formulations to penetrate bark. Standing dead material provides dead shade. Debris and leaf litter cover soil. Mechanical: grubbing roots, High $600–$1,000 Weeds sprouting from seed rapidly reinvade raking 1–2 years exposed soil. Mechanical: mowing Low $100–$300 Doesn’t kill roots, which rapidly resprout. 1–4 weeks Must be repeated often. Manual: slashing Low $400–$600 Doesn’t kill roots, which rapidly resprout. 1–6 weeks Must be repeated often. Manual: grubbing roots High $1,000–$3,000 Weeds sprouting from seed rapidly reinvade 1–2 years exposed soil. 1 Effectiveness at reducing competition for site resources; duration is the period that competition is significantly reduced. 2 Site preparation costs for each practice are highly variable and depend on site-specific situations. Costs listed here reflect a typical range of site conditions, but actual costs might be higher. Lower costs are associated with larger areas, easier ground, and forestry or agricultural contractor rates. Higher costs are associated with smaller projects, difficult conditions, and landscape contractor rates.

Riparian Tree and Shrub Planting in the Willamette Valley 13 Hand scalping (i.e., scraping the veg- freshly tilled field can be a sticky mess Formulations etation down to bare mineral soil with at planting. Rototilling strips (3 to Several formulations of both glypho- a shovel or planting hoe) is a simple 4 feet wide) can minimize some of sate and triclopyr can control method for removing grasses and her- these drawbacks. blackberry, Scotch broom, and other baceous weeds at planting (figure 14). woody species. Chemical formulation Subsoiling, or ripping, is a special form For this method to be effective, you and timing greatly affect effective- of tillage that may be justified in cases need to clear a 3- to 4-foot-wide area ness on target weeds and sensitivity of of serious soil compaction, such as and remove many of the roots. This nontarget plants. These chemicals will on pastures used for winter grazing. is labor intensive and provides only damage or kill the hardwood trees and Combine tillage with mulch mats or temporary relief from competition. shrubs commonly included in ripar- other methods to maintain the target Hand scalping usually needs to be ian plantings, which is why controlling weed-free area after planting. repeated at least once during the first weeds during site preparation, before growing season and also the following planting, is so important. Use extreme year. Using mulch mats or other mulch Chemical control care when spraying, especially near materials after hand scalping can help Herbicides are an effective, and versa- riparian areas. prevent weed reemergence (Step 5, tile, method for controlling perennial page 18). weeds before planting. They can be Consult the Pacific Northwest Weed Management Handbook (http:// Mechanical scalping with a brush- applied with power-driven spray equipment or backpack sprayers to pnwhandbooks.org/weed), the Oregon blade-equipped tractor or other Department of Forestry, your local soil specialized equipment can be an effec- provide control across a range of ter- rains without soil disturbance. Use and water conservation district, and tive means of removing brush if roots your local Extension office for more are also removed. This intensive and herbicides according to your needs; create weed-free patches or strips to information about formulation and disruptive method is not suitable for timing of herbicide applications. Also many restoration situations because it ensure good survival, or use a broad- cast application to clear the entire site. see “Important information about can lead to soil compaction, erosion, using herbicides” (page 15). and weed invasion. Timing is critical, and herbicide effec- tiveness depends on the chemical used Manual pulling is extremely labor and species targeted. Minimizing erosion intensive but can be effective if done “Light touch” site preparation may thoroughly (i.e., remove all roots and Timing reduce the risk of erosion but provide rhizomes of blackberry). Like till- If applied when weeds are actively poor control of competing vegetation. age and mechanical scalping, pulling growing, herbicides containing glypho- More aggressive site preparation may can also leave lots of disturbed soil, sate will kill common perennial grasses provide excellent weed control but increasing the risk of erosion and (e.g., reed canarygrass, bentgrass, and expose bare soil. This is a particular weed invasion. tall fescue), annual grasses, and other concern on or near stream banks that herbaceous vegetation. Application are washed by storm flows. Grazing is not an effective means rates will vary depending on the weeds of site preparation but may be suit- present. Glyphosate is a foliar-active Strategies for minimizing erosion: able in some cases once seedlings are herbicide, so it will not control weeds well established. that emerge from seeds after treat- • Prior to site preparation on ment. Additional methods will be stream banks and terraces, plant Tillage (including plowing, harrowing, needed to maintain weed control in the and establish willow cuttings and rototilling) can clear ground and first few seasons after planting; these near the channel to dissipate break up sod, allowing easy planting could include mulch, reapplications of stream energy. and a clean start. But unless it’s done glyphosate, or soil-active herbicides. • Remove competing vegetation repeatedly during the season before only in small patches along a planting, tillage alone is generally not For blackberry and other woody spe- stream rather than in a continu- very effective against perennial weeds cies, herbicide application is most ous section. because of their ability to resprout effective when plants have not been • Use erosion-control cloth and from root fragments. recently cut or mowed before spray- other bioengineering approaches ing. When this is not practical, mow (figure 15). Tillage can also create several unin- early in the season, and allow shoots to tended consequences. It leaves the regrow before spraying. • Use herbicides, and retain dead ground open and vulnerable to erosion material to protect soil. and recolonization by other weeds. A • Establish cover crops, or maintain untreated strips of vegetation.

14 Riparian Tree and Shrub Planting in the Willamette Valley Figure 14. Scalping provides only a temporary “leg up” on weed competition. Photo by Paul Oester, © Oregon State University.

Figure 15. Erosion-control matting was used on this section of Thompson Creek in Jackson County, Oregon, after a steep, eroding bank was graded back to a more desirable angle, exposing bare soil. The site was revegetated with willow cuttings (visible as stakes in the fabric) and grass. Photo by Applegate Partnership and Watershed Council.

Important information about using herbicides • Use a herbicide registered for your intended use. The Oregon Department of Agriculture regulates herbi- • Read the herbicide label, and follow the instructions. cide use. The Oregon Department of Forestry regulates The label is the law! applications on forestland, including forested riparian • When appropriate, use formulations that are labeled buffers. Land in other land-use categories may have dif- for aquatic use. Consider the toxicity of both the her- ferent regulations. Contact the appropriate agencies for bicide and the surfactant. current information about restrictions on herbicide use near streams. • Mix herbicides well away from riparian areas. • Wear protective clothing and safety devices as the See the Pacific Northwest Weed Management Handbook manufacturer’s label instructs. (http://pnwhandbooks.org/weed) and other resources listed • Avoid spraying on windy or hot days (above 75°F) under “For more information” (page 27), for more details to minimize herbicide spray drift and risk of volatil- on herbicide application and regulation. ization (turning into a vapor). The risk varies with the herbicide. • For herbaceous vegetation, spot-spraying or wipe- on techniques are often a suitable alternative to broadcast applications. • For woody vegetation, injection or cut-surface treat- ments can be appropriate.

Riparian Tree and Shrub Planting in the Willamette Valley 15 STEP 4. PLANT Checklist for Step 4: Plant your trees right Proper planting helps shape the future of your project; many problems with YOUR TREES RIGHT seedling survival can be traced back to improper care and handling. Well-established guidelines for tree planting in forestry and horticulture ☐☐ Plant at the right time of year—during the winter dormant season for generally are applicable for riparian bare-root trees and from fall through early spring for container seedlings. plantings. See The Care and Planting of ☐☐ Treat seedlings with care from the time they leave the nursery through Tree Seedlings on Your Woodland, OSU transport, short-term storage, on-site storage, and planting. Keep bare- Extension publication EC 1504 (http:// root plants cool and moist, and minimize physical damage. extension.oregonstate.edu/catalog), and ☐☐ Use proper tools and planting techniques. Select suitable microsites for other resources listed under “For more seedlings, such as the in shade of logs or on well-drained hummocks. information” (page 27). ☐☐ Use a planting layout suited to your access needs, maintenance plan, and equipment. Accommodate differing plant growth patterns and competi- When to plant tion among species (see Appendix C, page 24).

Plant bare-root seedlings during with seedling survival can be traced Table 6 lists recommendations for the winter dormant season, pref- back to improper care and handling: seedling care and handling, focusing erably when soils are above 40°F. on bare-root stock. Avoid planting during warm, dry, • Keep seedlings moist. Roots dry or windy weather. Plant container out rapidly when exposed to Planting tools and seedlings (ranging from small plugs sun or wind. If roots appear dry, to ball-and-burlap stock) from fall fine roots and root tips are likely techniques through early spring. If soils are moist damaged or dead already. Use the tool that is best suited to the and warm (above 40°F), fall planting • Keep seedlings cool. When seedling’s root system and to soil and may be advantageous since seedlings’ seedling temperatures exceed site conditions. roots may experience significant fall 42°F (and especially when tem- root growth. Plant hardwood cuttings peratures remain above 50°F for For bare-root and container plant- in the dormant season from late fall to more than a few hours), they ings, a heavy-duty, reinforced shovel early winter. begin “growing in the bag,” using works well across a range of Willamette energy needed for survival and Valley soil conditions and is easier Seedling care and growth after planting. for many people to use than a hoedad handling • Handle seedlings with care. planting hoe (figure 16). Match the Physical damage can result from shovel blade size to the seedling’s root Once dug or “lifted” at the nursery, crushing, dropping, and excess system. Other hand tools include the bare-root seedlings are vulnerable to vibration. Avoid tearing roots dibble and planting bar (suitable for damage during packing, transport, when unpacking seedlings. small plugs). Common garden shovels storage, and planting. Many problems are often unsatisfactory.

a b

Figure 16. Use suitable tools and good planting techniques, and take care to plant each seedling Figure 17. Auger planting can be helpful for well. Sturdy shovels (a) and planting hoes (b) can produce good results. large stock types. Photos by Brad Withrow-Robinson, © Oregon State University. Photo by Brad Withrow-Robinson, © Oregon State University.

16 Riparian Tree and Shrub Planting in the Willamette Valley Tractor-mounted or handheld power augers can work if the soil is not too heavy (clayey) or rocky (figure 17). Auger planting is especially useful for large container stock.

Take advantage of microsites (i.e., small differences in site conditions, such as soil, elevation, and shade, that affect seedling survival and growth). The shade of a log or other debris can help a seedling endure summer drought. Avoid or minimize haz- ards. For example, a depression that ponds each winter is not the right site for any but the most flood-tolerant species. Figure 18 shows common tree-planting problems.

Bare-root stock

• Create a hole large enough to position the roots naturally. • Prepare soil of adequate quan- Figure 18. Common tree-planting problems. tity and quality to fill back around roots without debris or Image from Rose, R., and P. Morgan. 1992. Guide to Reforestation in Western Oregon. Corvallis, OR: Oregon State University College of Forestry. Reproduced by permission. air pockets. • Position the tree straight and at Cuttings the proper depth, using the nurs- Spacing and ery soil line as a guide. Planting • Depending on cutting size and arrangement too shallowly is a common prob- planting depth, you can push The planting arrangement helps shape lem; the root collar (the point cuttings into moist soil or place stand development and, ultimately, where the highest root joins the them in holes excavated with riparian functions. Plant according to tree stem) should not be exposed. hand tools or machinery. the design you developed during your • Cuttings are less fragile than • Refill the hole, packing soil planning process (Step 1, page 2). Use bare-root seedlings, but general around the roots so the tree is a layout suited to your access needs, rules for handling, storage, mois- held firmly but roots are not maintenance plan, and equipment. If ture, and temperature apply. compressed. planting a mixture of species, be sure • Soak willow and cottonwood Plugs or container stock to accommodate differing plant growth cuttings in water for 1 to 10 days patterns and competition among • Keep the soil–root mass intact. before planting. species. See “Spacing and arrange- • Ensure that stock is well watered • Plant cuttings right side up ment” in Appendix C (page 24) for before planting. (i.e., the buds point up). more information. • Cuttings need to be planted • Prepare a hole large enough to Remember that planting is just one provide some loose soil around deeply enough so that emerg- ing roots can access moist step in creating a riparian woodland. the soil–root mass for unim- Other actions, such as weed control peded root growth. soils throughout the summer drought period. and thinning, will likely be required to keep the planting on track and achieve your functional goals.

Riparian Tree and Shrub Planting in the Willamette Valley 17 Table 6. Care and handling of bare-root seedlings. Stage Recommended practices Long-term storage (more than 3 days) • Store in a cooler at 33°F to 36°F. • Use packaging that prevents moisture loss. Most nurseries store and ship seedlings in waxed bags or boxes that “breathe” but prevent water loss. Transport from nursery • Use a refrigerated or insulated truck or reflective tarp (white exterior, silver-foil interior) over seedlings in an open-bed truck. • Do not expose seedling containers to direct sunlight. • Avoid using dark-colored tarps, which build up heat. • Travel during cool times of day if possible. Short-term storage (a few hours to 3 days) • Store below 42°F (ideal temperature range is 34°F to 36°F). Transport to planting site • Use proper packaging for seedlings and a reflective tarp. • Do not transport in the open; keep covered. • Do not stack bags more than two high. • When arriving at the site, store seedlings in shade. • Do not take more seedlings than can be planted in 1 day. At planting site • The greatest risk of damage from moisture loss, temperature, and physical handling is at this stage. • Handle seedling boxes or bags gently; do not throw or drop. • Reseal partially empty bags. • Avoid rubbing or tearing roots when taking seedlings out of the storage bag and putting them in the planting bag. Do not cram too many in the bag. • Seedlings may be dipped in water (for 1 minute at most) before placing in a planting bag, but do not store in water or the roots will die. • Do not leave seedlings unprotected on the ground, and make sure roots stay moist.

Checklist for Step 5: Take care of the planting STEP 5. TAKE CARE Maintenance after planting often makes the difference between success and failure. OF THE PLANTING

☐☐ Control competing vegetation for 2 years or more after planting to ensure Maintenance weed good survival. Controlling invasive weeds and other competing vegeta- control tion leaves more soil moisture and other resources for seedlings. The task at this stage is to maintain the ☐☐ Minimize animal damage problems—from livestock or wildlife—by using weed control achieved before plant- seedling protective devices, fencing, or repellents as needed. Try to antici- ing. Without continued control, weeds pate problems during your initial site assessment (Step 1, page 2), but will quickly return and affect seedling monitor and respond to problems if they occur. survival and growth. This is a common ☐☐ Irrigation can help improve seedling survival and growth, particularly for source of failure in riparian plantings. water-loving species on droughty soils. Consider the labor and expense involved, and select species that can survive on the site over the long term Once the planted species begin to without irrigation. shade a significant portion of the ☐☐ Visit the site periodically to monitor seedling survival and growth and ground, weed control becomes much determine maintenance needs. The first season after planting is the most easier. The time required to reach this critical, but maintenance may be needed for several years before seedlings stage varies. With effective weed con- are free to grow. trol, conifer plantings on unirrigated,

18 Riparian Tree and Shrub Planting in the Willamette Valley upland sites in western Oregon com- monly reach this point (called “free to grow”) in 4 to 6 years. There is less research or experience for riparian plantings to guide us, so plan for ongo- ing weed control in your planting for at least that long.

An added challenge in postplant- ing vegetation control is the need to mow, trim, or spray around vulner- able seedlings. If site preparation was effective, the main concern will be annual grasses and broadleaf weeds. Try to maintain the same control tar- gets established before planting (e.g., a 3-foot by 3-foot or 4-foot by 4-foot Figure 19. Mulch mats under ponderosa pine Figure 20. Organic material such as bark or patch or a 3- to 4-foot-wide strip). seedlings on a dry site in southwest Oregon. wood chips is often used as an inexpensive Photo by Applegate Partnership and Watershed Council. form of mulch and weed protection. Mowing is popular in young plant- Photo by Applegate Partnership and Watershed Council. ings. With available tools ranging from tractor-mounted mowers to handheld weed trimmers, mowing can be a source of weed seed, are not planting stock and controlling weeds can keep woody weeds under control as effective as weed mats for suppress- to promote rapid seedling growth across a range of terrains and plant- ing weeds, and may decompose too will help minimize many animal ing sizes. Mowing alone is not a good quickly or be swept away by floods. damage problems. way to control herbaceous plants and gives only modest relief from Herbicides can be an effective and Beaver and nutria can cause extensive moisture competition. efficient way to control weeds after damage to young seedlings. Removing planting, but seedlings are also sus- these animals may be an option; how- Mulches are effective for suppressing ceptible to commonly used herbicides ever, the site will likely be repopulated weeds around planted seedlings and (e.g., glyphosate). Avoid damage by from adjacent areas. Plantings quickly retaining moisture into the summer. directing spray at weeds and shielding grow beyond nutria but may remain Various mulch materials are available. seedlings to prevent contact with leaves attractive to beaver for many years. or green bark. Glyphosate and other Weed mats are made of woven syn- foliar-active herbicides have no soil Protection methods include individual thetics, paper, or other materials activity; they kill what is already grow- tree protectors (e.g., 2- or 4-inch wire (figure 19). They are placed over bare ing but don’t prevent establishment of mesh cages), chicken wire or sheet ground and fastened with landscape new weeds. Two or more treatments metal loosely wrapped around larger pins or rocks and soil. Commercial may be needed each season to control tree trunks, and fencing between the products include Vispore, Pak, and emerging weeds. Many formulations planting and stream. Brush Blanket. Longevity varies from of glyphosate are available. Check the one to several seasons. Mats come Depending on your situation, you label to see if a product allows your in various sizes; the recommended may be able to meet your objectives intended use. minimum is a 3-foot square. Mats are using a species not preferred by beaver, effective against grass and forbs but not such as ninebark. Consult with local resprouting woody vegetation. Mats Animal damage control experts. Small, isolated plantings have several disadvantages; they are Animal damage is another common that are the only woody plants in the relatively expensive ($0.75 or more per cause of plant mortality in riparian neighborhood are more attractive mat) and labor intensive to install, pro- plantings. Hardwood species are par- and more vulnerable and will likely vide shelter for rodents, and can move ticularly attractive to many animals. require more protection than large if the area floods. Carefully assess the need for protec- plantings adjacent to other areas of tion, taking into account the food and woody vegetation. Organic materials used for mulch- shelter available in the area for various ing include straw and wood chips. animal species. Physical methods of Deer typically browse young seedlings Newspapers, cardboard, and other low- damage prevention (e.g., fences, cages, early in the growing season, when new cost alternatives can be used as mats. and tubes) are useful, but they are also shoots are tender. Deer will browse These materials are inexpensive and expensive and require periodic inspec- up to about 3.5 or 4 feet. If deer are readily available (figure 20), but they tion and maintenance. Using large a problem, you need to protect trees’

Riparian Tree and Shrub Planting in the Willamette Valley 19 leaders until they grow past this height. 1 to 2 inches in diameter. Most damage equipment, irrigation may be feasible If you fence an area, the fence must be occurs during winter. The most effec- and effective. On other sites, irrigation at least 8 feet high to keep out deer. tive control is to eliminate cover by can be time consuming and expensive. mowing grasses short and eliminat- Tree shelters (figure 21) and plastic ing grassy weeds near seedlings. The Irrigation is most appropriate under mesh tubing, supported with a bamboo standard 3-foot by 3-foot or 4-foot by the following conditions: or wooden stake, are effective but 4-foot area used to reduce weed com- • During the first one or two grow- expensive and labor intensive to install petition works well for preventing vole ing seasons, to help seedlings ($3 to $6 per tree installed). Big-game damage, too. Tree shelters and alumi- establish repellants (e.g., Deer-Away and BGR) num foil (wrapped around the base of must be applied every 2 weeks in seedlings) can also protect seedlings. • On very coarse soils (e.g., sandy spring and early summer to be effec- or gravelly) with minimal water- tive against lighter browsing. Bud caps, Livestock (e.g., cows, horses, sheep, holding capacity flexible netting, and other materials are goats, and llamas) find young seed- • When planting water-loving less expensive than tree shelters and lings palatable and can heavily damage species (e.g., alder, willow, and sometimes prevent browsing. unprotected seedlings. The best cottonwood) way to keep livestock out of planted • When water rights are available Mice and voles can be very damaging areas is standard woven wire or to young plantings. They can thrive electric fencing. Irrigation methods include sprinklers, under a tall, dense cover of grassy drip systems, and hand watering. Select weeds. When vole populations surge, Irrigation a method on the basis of cost and avail- they will eat the bark on seedlings of all able equipment, labor, and water. If species, girdling and killing trees up to Although all plants can benefit to some you don’t have a water right to irrigate, degree from irrigation, it is usually not you may have to carry water in from essential. Selecting appropriate spe- off site. Contact the Oregon Water cies and planting stock, using proper Resources Department (http://www. handling and planting techniques, wrd.state.or.us/) for more information. and effectively controlling weeds will help ensure success in the absence of For maximum benefit, begin watering supplemental water. by early summer, before plants develop high levels of moisture stress. Plan to Irrigation can help seedlings survive water every 10 to 14 days, tapering off summer drought and improve seed- as summer progresses. Drying down ling vigor and growth. Hardwoods at the end of the growing season helps are more susceptible to drought than induce dormancy and increase winter conifers. Irrigation will be a temporary hardiness, so avoid frequent irrigation practice, so you must select species that in late summer. will survive without irrigation after Figure 21. Tree shelters protect seedlings from they are established. Tree seedlings may not expand their several forms of animal damage but are labor root area much in the first growing intensive and expensive to install. Carefully evaluate the need for irriga- season. They depend on nearby soil tion. If your planting is on farmland Photo by Donna Schmitz, Benton Soil and Water for moisture. Monitor this area. Water with water rights and irrigation Conservation District. deeply and slowly to thoroughly wet the rooting zone.

20 Riparian Tree and Shrub Planting in the Willamette Valley STEP 6. MONITOR Checklist for Step 6: Monitor and learn from results Monitoring is an essential part of a successful project, but in practice it is AND LEARN FROM often neglected.

RESULTS ☐☐ Build monitoring into your initial project plan. Monitoring your riparian plant- ☐☐ Inspect the planting early in the first growing season to assess problems ing allows you to complete several while there is still time to address them. Plan for one or more follow-up essential activities: inspections during the first growing season and annual inspections there- after until trees are free to grow. • Identify immediate maintenance ☐☐ Document the project. Keep a log of project activities and monitoring needs to ensure trees survive observations. and grow. ☐☐ Establish photo points to document change in riparian conditions over • Determine whether goals for time. Also consider more intensive monitoring or educational efforts, tree survival and growth are such as demonstration plots. being met (implementation monitoring). • Record all project activities by Photo monitoring • Determine whether goals for date in a project log. A series of photos over time is a pow- riparian functions are being met • Note results from periodic visual erful tool for documenting starting (effectiveness monitoring). inspections and other forms conditions and changes over time. • Improve future riparian res- of monitoring. Mark photo points (reference points) toration efforts by learning with steel pins or rebar so they can Consider marking the locations of which treatments or techniques be found in the future. Document planted trees with surveying ribbon or worked, which didn’t, and why the location of photo points in your wire flags. Although time consuming, (adaptive management). project log, and indicate the direction this will make it easier to locate trees • Document project imple- (compass heading) the photographer is for needed maintenance and moni- facing from the photo point. See “For mentation and results for toring and help ensure that you don’t funding agencies. more information” (page 27) for addi- accidentally damage or cut trees. tional resources on photo monitoring. Recordkeeping and Periodic visual inspection Other monitoring techniques evaluation This is the simplest and most impor- Most riparian monitoring will focus tant type of monitoring. The main on project implementation: Did the Before implementing the project, purpose is to see how the planting is planted trees survive, and are they develop a monitoring plan that doing and to decide what, if any, cor- healthy and vigorous? What problems addresses these questions: rective actions are needed to make sure require immediate attention? These trees survive and grow adequately to • What do you want to monitor questions can be addressed largely meet project goals. Plan for a visual through periodic visual inspections. (e.g., tree survival, shade, and inspection of the planting site at least bank stability)? once per season: More intensive monitoring techniques • How will you measure or evalu- can provide quantitative informa- ate these items? • Are grasses or other weeds tion that is objective, repeatable, and • When do key monitoring tasks encroaching on or threatening to statistically valid. These approaches need to be done? overtop planted trees? are important for evaluating project • What is appropriate given your • Is there evidence of browsing, effectiveness but are expensive and goals, time, skills, and budget? girdling, or clipping of stems? time consuming. • What steps need to be taken to Good documentation is essential: correct the problems? Regardless of the technique used, it’s important to follow a consistent format • Are trees vigorous and healthy? • Prepare an overall project for recording measurements and description including location, • Are trees of some species or trees taking notes on project conditions. site conditions, site preparation, in certain areas doing better than and maps and descriptions of others? If so, why? Appendix D (page 26) lists examples of planted areas to be monitored. Note your observations in the proj- common monitoring questions, objec- • Compile planting records, and ect log. The most critical time for tives, and techniques. See “For more note what was planted, where, inspection is the spring after plant- information” (page 27) for additional and how. ing, while there is still time to address resources on monitoring. emerging problems.

Riparian Tree and Shrub Planting in the Willamette Valley 21 APPENDIX A. KEY RIPARIAN FUNCTIONS, SUPPORTING VEGETATIVE CONDITIONS, AND RIPARIAN BUFFER DESIGN CONSIDERATIONS Vegetation conditions and Riparian functions functions supported Riparian buffer design considerations Provide shade to keep Shrubs and trees on the sunny side of the stream South and west sides of streams are most critical for water cool. shade plantings. Buffer width depends on stream Provide foliage to block sunlight. size, slope, and orientation. This function can be attained relatively quickly. Stabilize stream bank to Trees and shrubs on the stream bank and (on small streams) A stream bend’s inside bank requires a smaller prevent erosion. in the active channel buffer; its outside bank requires a larger buffer to account for channel migration. Vegetation within Roots hold soil, and stems slow water to reduce erosive force. 25 feet of the channel provides most of the buffer’s stabilization. This function gradually increases with development of surface cover and root structure. Filter nutrients and Trees and shrubs at the upland edge of the riparian area Sediment filtration depends on slope, soil type, and sediments to maintain other factors, such as the presence of drain tiles. A high-quality water. Vegetation cover slows and filters water flowing from 50-foot buffer can provide substantial filtration of adjacent uplands. Plant roots take up nutrients from the sediment from overland flow. Larger buffers may be soil solution. needed to take up soluble nutrients and herbicides. Modify stream flow; create Large trees falling into the stream Most debris comes from trees directly adjacent to resting cover pools or the stream channel. Landslides, floods, and debris retain gravel to improve Woody debris lodged in the streambed slows and diverts flows can also provide significant debris, depending fish habitat. water, causing gravel to accumulate. Water plunging over and on landscape conditions beyond the riparian area. circulating around woody debris forms and maintains pools. Provide off-channel Trees and shrubs along low areas of floodplain Enhancement of existing sloughs and side channels refuge. may yield high-value benefits for fish habitat. This Provides cover and slow-water areas for small fish function can be quickly attained. overwintering in the lower Willamette system.

Provide nutrients to enrich Vegetation overhanging the stream Most benefits come from vegetation hanging over or aquatic system. directly adjacent to the channel. Deposits leaves and twigs. Insects fall from vegetation into the water. Forms the basis of the aquatic food web in some streams. Provide habitat for Dense areas of shrubs with an overstory including large live Buffer width depends on habitats and species of nesting, roosting, trees and dead trees (snags) concern. Large buffers needed for wildlife corridors. foraging, and other Even with fast-growing species, development of terrestrial wildlife activity. Shrubs and trees provide nesting and hiding cover and may these functions may be very slow. provide corridors for wildlife passage.

22 Riparian Tree and Shrub Planting in the Willamette Valley APPENDIX B. PROMOTING NATURAL REGENERATION Promoting natural regeneration (i.e., competition. Many riparian species growth from seeds, roots, and stems) also regenerate vegetatively, includ- a of trees and shrubs already on the site ing resprouting from the root crown, can help establish desired vegetation root suckering, layering, and sprout- with less expense and effort than plant- ing from stem fragments. This makes ing seedlings. This may be the core of a natural regeneration a useful but passive restoration strategy or a way to often unreliable source of recovery in add diversity to a planting. years when seed production is low or matches poorly with natural distur- Other advantages of natural regenera- bances, or when you want to develop tion are that species are genetically woody cover farther from the active adapted to local conditions and, espe- stream channel. cially with vegetative reproduction, set for rapid growth. Greater reliance on What can be done natural regeneration can also increase the cover of desirable riparian plants. to enhance natural However, natural regeneration alone regeneration? generally is not a reliable way to meet b establishment goals for species compo- • Kill or cut back competing veg- sition or an adequate number of trees etation. Riparian plantings often and shrubs. contain more desired woody plants than first meet the eye. Conditions must be right for natural Locate and flag these plants regeneration to occur: before cutting. • Stimulate root suckering, layer- • Temporary freedom from vegeta- ing, and sprouting by cutting tive competition back competing vegetation twice • Available sources of seed (of per year. Black cottonwood desired species) (Populus trichocarpa) and sand- • Abundant soil moisture bar willow (Salix exigua) sprout vigorously from underground Conditions for natural regeneration shoot buds on lateral roots. A are often most favorable close to the Figure 22. Two seasons after Himalayan temporary reprieve from com- stream, where there is abundant soil blackberry was cut back on this site (a), petition can help these species moisture and where seasonal flood- sandbar willow has made a good recovery (b). move rapidly into previously ing prevents invasive species such as Photos by Max Bennett, © Oregon State University. unoccupied areas (figure 22). blackberry from establishing. Natural regeneration also frequently occurs in • Minimize cover of competing a pulse after a disturbance, such as a vegetation to stimulate germina- major flood that has cleared streamside tion and rapid early growth of vegetation and exposed or deposited seedlings of desirable species. A fresh sand and gravel. large amount of seed falls into riparian areas, but new plants can These conditions are ideal for ger- regenerate only under favorable minating seeds of black cottonwood, conditions. It isn’t important to willow, alder, and many other ripar- eliminate competitors entirely, ian species. They are not favorable but you must reduce their cover for many conifers. Oregon ash, to low levels while desirable spe- Oregon white oak, and hawthorn cies get established. (both the native Douglas and invasive • Protect plants from livestock or English) are likely to spread into wet other animal damage with fenc- meadow areas, even with some weed ing or individual tree protection.

Riparian Tree and Shrub Planting in the Willamette Valley 23 APPENDIX C. PROJECT DESIGN FEATURES AND CONSIDERATIONS You considered functional goals (e.g., shade, bank stabilization, and Location habitat) when planning the project Some functions are more location- and selecting species. Optimize those dependent than others. Vegetation on functions with a thoughtful layout. the south and west sides of the stream Consult others; staff from soil and provides direct shade, which helps water conservation districts, watershed moderate water temperatures more councils, and the Natural Resources than similar vegetation on the north Conservation Service generally have side. Habitat functions (e.g., food and extensive experience with these practi- nesting) are not strongly related to cal design issues. position. Bank stability may be a key functional goal in areas subject to scour or stream meanders. Buffer width University. State © Oregon photo, File There is no one-size-fits-all buffer Figure 23. Riparian buffer installed next to width. Wider buffers generally provide Access requirements a farm field. A stream is at left, outside the more benefits, but beyond a certain Provide access and adequate space photo frame. In this case, livestock fencing (at size, there may be relatively little between trees for any machinery to right in photo) is essential to the success of the increase in benefit for a relatively large be used. Consider the benefits of rows buffer planting. increase in buffer width. for maintenance (e.g., mowing and spraying). Regular rows and adequate Spacing and Optimal buffer widths vary depend- spacing between rows (5 to 10 feet) ing on the desired riparian functions. are needed for most small tractors and arrangement For bank stability, relatively narrow ATVs. Rows can look natural; they do The future diversity of your riparian buffers suffice. For wildlife habitat or not need to be straight lines. Sweeping woodland will depend not just on the travel corridors, wider buffers may be curves work, too. Closer spacing and species you select but also on the spac- required (see Appendix A, page 22). irregular tree distribution are OK if ing and arrangement of your planting. you will use smaller mowers, backpack Your design should reflect both short- Consider a variable-width buffer. sprayers, or hand tools. and long-term goals. Good places for wider buffers are the outside bank of a stream bend (so the Plant spacing entire buffer isn’t lost when the chan- Fencing and other Appropriate plant spacing depends on nel migrates) and on low terraces and livestock and wildlife several (sometimes competing) factors: low-gradient reaches (to enhance bank controls stability and off-channel habitat were • Tree size, stand structure, and flooding is more frequent). Standard woven wire and electric fenc- species composition needed to ing are adequate for domestic livestock meet a project’s functional goals On forestlands, the Oregon Forest but require maintenance (figure 23). • Species characteristics (size, Practice Act dictates minimum buffer Carefully managed rotational livestock widths. On agricultural lands, there growth rate, form, and grazing can be compatible with ripar- shade tolerance) are no specific buffer-width require- ian planting without fencing out the • Need for rapid establishment and ments; owners must comply with local entire riparian area. However, cross- occupancy by seedlings (increas- water-quality management plans estab- fencing to establish multiple pastures ing their ability to compete lished under Oregon Senate Bill 1010. is key. Contact your local soil and water con- with weeds) servation district or watershed council Deer and elk can jump easily over • How long and how well you can to learn about local water-quality livestock fencing, so 8-foot or higher control competing weeds management plans. City or county fencing is needed to protect plants • How quickly and to what jurisdictions may have ordinances dic- from these animals. This can be pro- degree seedlings compete tating buffer width. hibitively expensive; individual tree with each other (affecting protectors often are used instead. An tree size, stand structure, and 18-inch-high chicken wire fence placed species composition) between the stream and planted stock • Your ability to thin in a keeps out most beaver and nutria. timely manner

24 Riparian Tree and Shrub Planting in the Willamette Valley Mixed-species plantings Slower-growing trees fall behind and, Strategies to allow slower-growing Mixed-species riparian plantings gen- depending on degree of crowding and species (of a given shade tolerance) to erally serve two purposes: their shade tolerance, may eventually survive longer include wider spacing die unless the planting is thinned. In a (figure 24b) and clusters of individual 1. They provide “insurance” to single-species stand, this competition species (figure 24c). Plants at the edge cover uncertainties associated affects the size and number of trees of a cluster of slow-growing species with seedling survival and spe- surviving but not the species present. will be lost, but those inside are a safe cies adaptation. In a mixed-species planting, competi- distance from faster-growing competi- 2. They establish a diverse plant tion favors one species over another tors and can survive. Clustering is a community that will provide key and tends to shift the planting toward good strategy to use when you want to habitat functions in the future. the faster-growing species. Diversity plant close enough to cover planting of the planting decreases as slower- losses and encourage rapid site cap- The most common approach to devel- growing species die, and any functional ture but may be unsure of your future oping a mixed-species planting is to goals associated with these species capacity for management (both weed use a random mix of species. This won’t be realized. control and thinning). serves the first purpose but not neces- sarily the second. Research with a wide range of plants Consult with Oregon State University has demonstrated that this interac- Forestry and Natural Resources Differing early growth rates affect tion is more pronounced the more Extension for more information about how species interact and compete. dissimilar the growth rates among competition, stand development, and Trees that establish and grow quickly competing species. The interaction also spacing and arrangement strategies for often do so at the expense of neigh- is sensitive to plant spacing (density). creating diverse riparian forests. boring plants, occupying space and The closer the spacing, the faster and consuming resources needed by each. more complete the displacement of the slower-growing species (figure 24a).

Research and a demonstration of mixed-species plantings Growing mixtures of species is challenging and requires good infor- b mation about growth rates and other plant characteristics. Unfortunately, such information isn’t available for many restoration species growing in riparian conditions. Ecological principals and established forestry practices can provide useful guid- ance, but demonstration and applied c research are desperately needed.

A network of simple plots across a range of Willamette Valley soils would provide valuable information for current and future restora- tion project managers. Contact the authors if your watershed council or Figure 24. Mixed-species plantings have many advantages, but how the species are mixed at soil and water conservation district planting can lead to different outcomes as the trees and shrubs grow: (a) two species with would be interested in contributing different growth rates intermixed at a close spacing, (b) two species intermixed at wider spacing, to this effort. and (c) two species clustered.

Riparian Tree and Shrub Planting in the Willamette Valley 25 APPENDIX D. SAMPLE MONITORING QUESTIONS, OBJECTIVES, AND TECHNIQUES Monitoring question Objective Technique How many trees, stream Document the project for project Include this information in your project documentation and frontage, or area planted? managers, funders, etc. monitoring plan. Where? Are the planted trees Assess immediate threats to tree vigor and Visual inspection of planting area. threatened by weeds or survival and need for action. Timing: The spring after planting is most critical. Inspect at least animal damage? once per season. Did the planted Determine overall success of the planting. Visual inspection or intensive measurement. Walk the site to get a trees survive? Is replanting necessary (if below some general sense of tree survival, or tally every tree or a representative threshold)? sample of trees to determine survival rate. Flagged tree locations can be helpful. Timing: Inspect at the end of the growing season. The first growing season is an important benchmark; most mortality occurs in the first year. Are the planted Evaluate success of the planting. Vigor is Visual inspection or intensive measurement. Indicators of vigor trees vigorous? one criterion. include plant size, leaf size, bud size, needle length, leaf length, and foliage color. Timing: Inspect during the growing season. How fast are trees growing? Determine overall success of the planting. Visual inspection or intensive measurement. Height is less Also, determine how growth varies by sensitive than diameter to effects of vegetative competition. planting site, species, treatment, and Thus, differences in diameter often are used to evaluate treatment other variables. effects, such as different site preparation methods. Are trees “free to grow”? “Free to grow” is an important benchmark Free-to-grow trees are vigorous, not threatened by competing for project success. At this stage, trees vegetation, and poised for further growth and site dominance should be able to dominate the site without additional intervention. Determining whether a tree is free without further intervention. to grow is somewhat subjective. Timing: Reaching free-to-grow stage is site specific. Upland conifers plantings usually require 4 to 6 years. Are trees doing better in Determine success of each section of Visual inspection or intensive measurement. Compare tree survival, one area than another? the planting. Also, learn about factors vigor, and growth (e.g., height, diameter, and stem volume). Areas may differ ecologically affecting plants on the site and what (e.g., soils and drainage) might be done differently next time. or in treatments (e.g., site preparation). What are the major reasons Learn about factors affecting plants on the Visual inspection or intensive measurement. Note any evidence trees died? site and what might be done differently of trees dying from overtopping/encroachment of competing next time. vegetation, lack of water, lack of nutrients, animal damage, etc. Is the riparian condition Determine whether riparian goals are Photo monitoring or intensive measurement. trend positive (e.g., is cover being met. of desirable vegetation increasing)? Did the project increase Determine whether riparian goals are Photo monitoring may show increases in stream cover. Intensive shade to the stream? being met. measurement (e.g., with a solar pathfinder or fish-eye lens) is needed to quantify increases in shade. Did the project reduce Determine whether riparian goals are Intensive measurement. nitrate input to streams from being met. adjacent farmlands?

26 Riparian Tree and Shrub Planting in the Willamette Valley FOR MORE ADDITIONAL RESOURCES To locate the watershed council in your area, visit INFORMATION http://www.oregon.gov/OWEB/WSHEDS/wsheds_councils_list.shtml The following publications are available through the Oregon State University Anderson, M., and G. Graziano. 2002. Oregon Department of Forestry. Extension Service Catalog (http:// Statewide Survey of OWEB Riparian Sources of Native Forest Nursery extension.oregonstate.edu/catalog): and Stream Enhancement Projects. Seedlings (annual catalog with seed Salem, OR: Oregon Watershed zone maps). http://www.oregon. Introduction to Conifer Release Enhancement Board. gov/ODF/privateforests/docs/ (EC 1388) ForestNurserySeedlingSources.pdf Crowder, W., and W. Edelen. 1996. Managing Himalayan Blackberry in Riparian Moisture Zones: Planting Oregon Watershed Enhancement Western Oregon Riparian Areas Locations of Woody and Herbaceous Board. 2004. Oregon Riparian (EM 8894) Species. Technical Note 31. Pullman, Assessment Framework. http://www. WA: USDA-NRCS Pullman Plant oregon.gov/OWEB/docs/pubs/OR_ Pacific Northwest’s Least Wanted List: Materials Center. RiparianAssessFramework.pdf Invasive Weed Identification and Management (EC 1563) Falk, D.A., M.A. Palmer, and J.B. Prichard, D. 1995. Process for Assessing Zelder (eds.). 2006. Foundations of Proper Functioning Condition. Pacific Northwest Weed Management Restoration Ecology. Washington, Technical Reference 1737-9. Denver, Handbook (WEED): http:// D.C.: Island Press. CO: U.S. Department of the Interior, pnwhandbooks.org/weed Bureau of Land Management. Fisher, R.A. 2004. Using Soil Seedling Care and Handling (EC 1095) Amendments to Improve Riparian Watershed Professionals Network. Selecting and Buying Quality Seedlings Plant Survival in Arid and Semi-arid 1999. Oregon Watershed Assessment (EC 1196) Landscapes. Vicksburg, MS: USAE Manual. (Developed for the Research and Development Center, Governor’s Watershed Enhancement Selecting Native Plant Materials for Environmental Laboratory. Board). http://www.oregon.gov/ Restoration Projects (EM 8885) OWEB/docs/pubs/OR_wsassess_ Hall, F.C. 2002. Photo Point Monitoring manuals.shtml Site Preparation: An Introduction for Handbook, Part A—Field Procedures. the Woodland Owner (EC 1188) General Technical Report PNW- Winward, A.H. 2000. Monitoring the GTR-526. Portland, OR: USDA Vegetation Resources in Riparian The Care and Planting of Tree Seedlings Forest Service, Pacific Northwest Areas. General Technical Report on Your Woodland (EC 1504) Research Station. RMRS-GTR-47. Fort Collins, CO: USDA Forest Service, Rocky Tree Buffers along Streams on Western Mountain Research Station. Oregon Farmland (EM 8895)

a b

Figure 25. A successful riparian planting along Evergreen Creek, Benton County, Oregon, in the year of planting (a) and after three growing seasons (b). Trees and shrubs were planted in meandering rows at about 525 plants per acre. Note that initial broadcast weed control (a) has been replaced with swaths of native grasses between herbicide strips in tree/shrub rows (b). Photos by Ray Fiori, Oregon Wetlands LLC.

Riparian Tree and Shrub Planting in the Willamette Valley 27 Use herbicides safely! • Wear protective clothing and safety devices as recommended on the label. Bathe or shower after each use. • Read the herbicide label—even if you’ve used the pesticide before. Follow closely the instructions on the label (and any other directions you have). • Be cautious when you apply herbicides. Know your legal responsibility as a pesticide applicator. You may be liable for injury or damage resulting from pesticide use.

Trade-name products and services are mentioned as illustrations only. This does not mean that the Oregon State University Extension Service either endorses these products and services or intends to discriminate against products and services not mentioned. © 2011 Oregon State University. This publication was produced and distributed in furtherance of the Acts of Congress of May 8 and June 30, 1914. Extension work is a cooperative program of Oregon State University, the U.S. Department of Agriculture, and Oregon counties. Oregon State University Extension Service offers educational programs, activities, and materials without discrimination based on age, color, disability, gender identity or expression, marital status, national origin, race, religion, sex, sexual orientation, or veteran’s status. Oregon State University Extension Service is an Equal Opportunity Employer. Published October 2011.