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<br />I <br />: I <br /> <br />I <br />I <br />'I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br /> <br />Woodward-Clyde <br /> <br />Mr. JeffBruggink <br />u.s. Forest Service <br />August 20, 1996 <br />Page 4 <br /> <br />width is dug into the bank, wire netting is stretched across the trench; coarse gravel, sod, <br />and reed-clumps are placed in the wire net; and the wire net is then drawn around the <br />material and then tied with wire. A row of stakes or planks are placed on each side of the <br />roll and attached to the wire for stability, The whole system is then covered just enough to <br />leave aerial stems exposed. The upper edge of the roll should not be more than 2 inches <br />above ground level. <br /> <br />Since the bank zone along Buffalo Creek will be exposed to considerable flooding and <br />current action, shrub-like willow, dogwood, birch and alder transplants or one-year-old <br />rooted cuttings are effectively used in this zone. These transplants or cuttings should be <br />planted I to 2 feet apart and in rows. Newly planted banks are usually subject to additional <br />erosion and the shrub plantings should have mulch placed over them to serve as temporary <br />protection, or held firmly to the bank using a long term natural/synthetic erosion control mat. <br />Erosion control mats should have the proven performance to withstand flows of 6-8 <br />ftlsecond for 48 hours duration. Branches of woody plants make good mulch and should be <br />the heaviest on outside curves of the stream where the current strikes the bank. The mulch <br />should be tied down with chicken wire or wire laced between stakes since the mulch may <br />float away when flooded. <br /> <br />Where severe erosion is expected, as is the case along Buffalo Creek, the bank zone should <br />be further protected using a combination of supportive measures. Supportive measures that <br />have been used successfully include willow barriers, fascines, wattles, and stone paving with <br />willow slips among the stones. <br /> <br />Willow barriers or mats are interlaced willow switches 5 to 6 feet long that are placed <br />perpendicular to the bank. The switches are cut from live willow plants and kept moist until <br />planting. The willow switches will sprout after planting, but care must be taken to obtain the <br />switches early in the growing season before the mother stock has started to grow <br />extensively, or in the fall following leaf defoliation. Willow switches are held together and in <br />place by wire or by willow hurdling (willow branches used as a strapping) fastened to stakes. <br />Willow switches are placed in a 6 inch deep excavation and are lightly covered with earth so .. <br />that the branches are set in each, but not completely covered. <br /> <br />Fascines, sometimes called contour-wattling, are lengths of willow switches or other <br />sprouting species packed together in a tight continuous roll 10 to 60 feet in length and 4 to 5 <br />inches in diameter. They are buried across the slope, parallel or nearly parallel to the stream <br />course, and supported on the downhill side by stakes. The sprouting attributes of the willow <br /> <br />96IXi0Vs..t.l.lLE498 8Il9f96(3:20PM)'MJcr:48 <br /> <br />Woodward-Clyde Consultants <br />