DA-15-00001 Palomino Fields Master File

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second. Woody materials in conjunction with herbaceous species should be considered for velocities less than 5 feet per second. Herbaceous materials alone can be used for velocities less than 3 feet per second. Engineered hard structures or bioengineering techniques may be needed in situations where the toe of the bank is unstable. hl these situations, refer to the NRCS Stream Restoration Design Handbook, National Engineering Handbook, Section 654. Species Selection During the reconnaissance, identify willow, cottonwood and other riparian species, local soil and site conditions and the moisture regime. If species identification is a problem, at least identify the growth form and conditions where the plant is growing (elevation, soils, zone, etc.). Species and/or growth form identification is important so the correct plant species can be matched to the right planting zone at the revegetation site. Willow species have several different growth forms. Willows come in all sizes, from small shrubs to large trees. There are three basic types of willows: tree -type, shrub -type, and creeping type. Tree -type species at maturity have a large crown, single or multiple stems, and dense basal area. They are usually taller than 20 ft. Shrub -type willows generally have smaller diameter multiple basal stems and rarely get taller than 15-18 ft. Creeping—type willows sucker profusely and are represented by coyote willow (Salix exigua). , Different growth forms of willows along the Snake River Cottonwood species have narrow to wide crowns and some species sucker (generally only about 10% of a stand will sucker) while others have very shallow root systems. In general, small to medium size shrub - type willows and rhizomatous or creeping - type willows are used for planting within the channel banks. These can be planted as live poles, vertical bundles or as clumps. Tree -type willows and cottonwoods are normally selected for the upper bank and floodplain areas near the transition zone and can be planted as large poles or clumps. Mature size and growth form will affect species selection. Large species can partially block or deflect stream currents. If the mature basal size of the selected species will block streamflow near the main channel or on adjacent floodplains, another species with more flexible stems should be considered. There are many species of willows that occur naturally in different habitats. Upland willow species are found in relatively dry areas not necessarily associated with seeps, bogs, or high water. Scouler willow, a common upland species, is rarely found on wet areas, but more commonly on or near moist areas such as springs or intermittent watercourses. Wetland willows are found growing in standing water or saturated conditions and are adapted to long periods of inundation.