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Cover crops and mulch are used very effectively in drainageways to reduce the detachment of soil by rainfall and runoff while providing seasonal protection and soil improvement. Cover crops provide protection from wind and water erosion during vegetation establishment periods when permanent vegetation is inadequate to provide adequate cover. Permanent vegetative (grasses, forbs and shrubs) cover provides the most significant and permanent long term solution to erosion control problems. The selection of species adapted to the climate and soils is one of the most important steps in achieving success. Woody plants are often desirable for the long term stability of a particular site. However, woody plants require time to develop sufficient size to control erosion adequately and the quick cover that can be obtained with grasses and forbs is needed in the interim. The principles for selection of herbaceous vegetation is based on a particular species adaptation to the site and its erosion control potential. The ideal species should have strong root development. A diverse mixture of plant species increases the assurance of a stand as i[ is difficult to anticipate all of the variables that will affect germination and stand establishment on any given site. Also, a monoculture is always more susceptible to disease or losses from abnormal weather condition. Thus, a mix of perennial grasses and forbs is used. Willow wattles and woody seedling transplants are installed in drainageways and serve as energy dissipaters for water and soil moving down the drainageway and provide long term stability. Woody plants filter and trap entrained debris (soil, small rocks, veg litter) and provide a series of areas with reduced slope angles on which vegetation can be established. Deep rooted woody vegetation prevents gully formation and will become part of the permanent stabilizing cover. Brush matting (crimping) is essentially a mulch of hardwood brush crimped into existing drainage cuts. The technique is employed very effectively in stream channels and on stream banks to protect against accelerated erosion rates when a channel needs repair. • Geotextiles, erosion blankets and other erosion control fabrics, are used effectively in reducing stream velocities and increasing sedimentation in drainageways. A variety of materials were used at Trapper Mine and include geoweb - a soil confinement system, C125 coconut blanket, and landglas erosion control fibers (landglas is tacked with CSS-1 emuls'rfied asphalt). 3.3 Flow Discharge readings for Coyote drainage were recorded from a 10-year, 24-hour parshall Flume located in the north end of the reconstructed drainageway. The peak (low for Coyote drainage in 1988 was 727 gpm (1.62 cfs) and occurred during the spring runoff period (3-27-88) (see attached Table 1). The peak Flow in 1987 (22.24 cfs) occurred as a result of a high intensity thunderstorm on June 7 (.74" ppt) and caused severe damage to a 2500' erosion control test plot located within the drainage. In 1988, a thunderstorm of similar intensity (.53' ppt) occurred on June 29th and resulted in a peak flow of only .02 cfs. The large variation in Flow rates between years can be attributed to less than normal winter and spring moisture (February-April 1988) and the construction of several (30) livestock ponds in the drainage basin in the late summer of 1987. Livestock ponds were constructed within the drainage bottom and on adjacent water harvesting diversion ditches which feed the main drainage. In 1988, additional livestock ponds (9) were constructed to further improve wildlife/livestock watering opportunities and decrease drainage flow rates. 3.4 Improvements and Repairs • Drainageway improvements and repairs were pedormed to provide benefits to all drainages treated in 1987- 88, as well as portions of undisturbed drainage segments. Drainage improvements included the Installation of several thousand shrub seedlings in 1987 treatment areas, the rock armoring of hay bale structures in