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moisture retention. The second tune is following completion of soil nxonsttuction and immediately prior to commencement of n;vegetation operations. Can; must be taken when ripping, disking or plowing topdressing so that operations avoid turning over the soil and bringing up excessive amounts of subsoil materials. Contour Furrows Contour furrows are placed perpendicular to the slope on the contour using a modified Rome disc, duck's-foot plow or similar agricultural implement Furrows are normally spaced 3 to 4 feet apart and may range from 6 to 12 inches in depth delpending upon soil characteristics. Prior to contour furrow construction, the slope contours should be staked by a hand level or instrument survey to aid the operator in placement on the contour. Care should be taken to avoid furrowing off contour. Interrupting the wntour on a periodic basis helps to ~+~~~+~+~P breaching and erosion problems associated with contour furrows that are placed off level. Land Imprinting Land imprinting is accomplished using a roller with any number of various geometric configurations. Normally the geometric pattern is repeated around the imprinter's drum, with two or three shapes being repeated in a non-linear or alternating fashion. The shapes used should promote their penetration and imprinting into the soil surface. Imprinting may be used on any slope where equipment can be operated. Because of its non-linear pattern imprinting is especially useful on steep slopes where equipment can't tie operated on the contour. Imprinting works best on mediwn-textured sods. Soils that art: too sandy do not imprint well because they fail to retain the imprinter's shapes; soils that are high in clay content may present problems with adequate penetration. Erosion Control Fabrics and Blankets Erosion control fabrics may be used on slopes where erosion potentials are moderate to high and where the application of mulch materials is either not physically possible or is not expected to adequately protect the slope during the vegetation estrrblishment period. Erosion wntrol fabrics may be installed perpendicular to or up and down the slope (Figure C-1). Fabrics should be installed per the manufacturers' specifications. Properly installed and maintained blankets are extremely effective in stabilizing soil and promoting vegetation germination and establishment 'their relatively high cost requires that they be used judiciously. Wattling Wattles are typically used for freshly disturbed slopes or as a reclaaialion measure for seriously eroded and barren slopes. I-hstorically, wattling involves the embedding of tree or shrub branches into the soil surface (Figure C-2 and Figure C-3). 71te woody material is tied into bundles and placed on the contour. Wattling is normally used on wetter sites, such as ephemeral or intermittent draws, where the woody materials have an opportunity to take root and grow. While this project location likely provides limited opportunrtres for employing classic wattling, it may be valuable as a stabilization tool in some areas. The method rs expected to be successful because it uses mechanical and vegetative means to promote stabilization. Therefore, it should have good applicability on steep slope areas that are difficult to access with machinery. In those situations excelsior erosiion control blankets may be rolled width-wise to serve as wattling materials. The 4afoot-long to 80-foot-long roll of blanket may be cut to desired length and installed similarly to wabfles made of wood. The roll will be partially buried in a shallow trench cut on the contour. It is expected that C-2