2000-07-26_GENERAL DOCUMENTS - C1981017

Home Browse Search

Table 1. 1999 Outslope Seed Mixture Species Scientific Name Variety # PLS/Acre Kentucky Bluegrass Poa pratensis Banff 0.25 Elymus Slender Wheat grass trachycaulus San Luis 4.00 Mountain Brome Bromus mar inatus Bromar 4.00 Sheep Fescue Festuca ovina Covar 1.50 Hard Fescue Festuca ovina Durar 1.60 Red Fescue Festuca rubra Pennlawn 1.10 Timothy Phleum pratense Climax 0.25 Tufted Deschampsia Hairgrass caes itosa Peru Creek 0.20 Orchard grass Dactylis glomerata Latar 0.50 White Dutch Clover Trifolium repens Ladino 0.50 Cicer Milkvetch Astragalus cicer Monarch 1.00 Blue Flax Linum lewsii Appar 1.00 Yarrow Achillea millifolium VNS 0.10 Rocky Mountain Penstemon Penstemon strictus Bandera 0.50 TOTAL 16.5 #/Ac. PLS In order to help control sediment at the base of three slopes accessible by equipment, sediment traps were constructed. In one instance, this required the excavation of existing, but non-functional, sediment traps. These broad shallow traps were excavated so that runoff from a portion of two mines and the run out from a large avalanche area would pass through a sequence of three traps, allowing water to stand for a short period of time, permitting sediment to drop out of suspension. Locally obtained willow cuttings were planted around the perimeter of these sediment traps in order to further slow water as it exited the traps, and to provide for habitat enhancement. In some areas, adequate room to construct sediment traps did not exist. At one such location, logs and timber were placed into semi-concentric arrangements along the length of the slope base. This pattern tends to slow water velocities and allows sediment to accumulate, minimizing off-site migration. This approach is a short term sediment control measure, due primarily to the limited detention time afforded by the logs and timber. Intensive shrub and tree planting occurred at this location to provide for a greater degree of long term sediment control. 5