Influence of poultry manure treated with ammonia suppressants on composting and yield of the commercial mushroom

Poultry manure is the most widely used nitrogen supplement for mushroom com posting. It has been reported that treating poultry manure with ammonia-sup pressants will reduce the release of ammonia while chickens are being raise d. Treated poultry manure has historically caused composting and production problems for the mushroom industry. Newer ammonia-suppressant materials ha ve been developed to bind ammonia in the poultry houses, but they have not been tested to determine their influence on mushroom substrate preparation. Experiments were conducted to determine if mushroom growers can add treate d poultry manure to a standard wheat-straw-bedded horse manure formula with out affecting the composting process, mushroom growth, or yield. Treated po ultry manure was added, on a dry weight basis, to straw-bedded horse manure as a direct substitute for untreated poultry manure. Analysis of the vario us composts for nitrogen, ammonia, ash, pH and percent moisture showed that all composts were similar in both physical and chemical characteristics an d the values were considered normal by industry standards. Treated poultry manure composts were not significantly different (p=0.05) on a basis of kil ograms of mushrooms produced per square metre or kilograms of mushrooms per kilograms dry weight of compost.