Monday, November 13, 2006
26-12

Effect of Manure Feedstocks on Compost Quality.

Christopher Baxter and Steve Wilkens. Univ of Wisconsin - Platteville, 1 University Plaza Tower 208, Platteville, WI 53818-3001

Production of manure compost is an increasingly used tool in manure and nutrient management. Successful management of compost requires a thorough understanding of the feedstock’s effect on compost quality, particularly if the desired end-use is marketable compost. The objective of this study is to determine the impact of various manure feedstocks on several compost quality parameters. Feedstocks used were: 1) swine pack manure, 2) cattle (mixture of dairy and beef) pack manure and 3) solids separated  from liquid dairy manure. Feedstocks were placed in windrows approximately 1.5 m high and turned via mechanical compost turner every 3 d for the first 15 d, followed by weekly turning in the 28d thereafter. During the composting process, temperature was monitored daily and moisture content was monitored weekly. Samples of raw feedstocks and composted manure were collected prior to and after composting. Feedstock/Compost quality parameters that were evaluated included pH, density, soluble salts, weed seed viability, compost maturity (C/N and NH4-N/NO3-N ratios), compost stability (CO2 evolution), and available nutrients (N, P, K). The effects of manure feedstock type on quality of finished compost and management recommendations for the manure feedstocks evaluated will be discussed.