Steep Cut Slope Composting: Field Trials and Evaluation

摘要

Three different depths of compost and five compost retention techniques were tested to determine their efficacy and cost effectiveness for increasing the establishment of native grass seedings and decreasing erosion on steep roadside cut slopes in southwest Montana. The depths of compost selected were: 0.32 cm (0.13 in), 0.64 cm (0.25 in) and 1.27 cm (0.5 in). The compost retention methods utilized a coconut-straw fiber fabric, lightweight plastic netting and three commercially available tackifiers: (1) a polymer emulsion liquid, (2) a guarbased water dispersible formulation, and (3) a Plantago-based seed husk powder. Compost application rates of 1.272.54 cm (0.51 inch) are recommended for establishment of sufficient vegetation cover, estimated to result in 1626 percent native bunchgrass cover in arid climates in Montana. These recommended application rates are estimated to cost between $41,160 and $82,171/hectare ($16,657 and $33,254/acre) based on plot construction methods from this study using a blower truck. Compost retention treatments employing physical retention of compost such as coconut-straw fiber fabric or lightweight plastic netting were effective in limiting the loss of applied compost. The tackifiers gave confounding results on their ability to retain compost.