Use of Wood‐Based Materials in Beef Bedded Manure Packs: 1. Effect on Ammonia, Total Reduced Sulfide, and Greenhouse Gas Concentrations

The objectives of this study were to determine the effect of using corn stover or three different wood‐based bedding materials (kiln‐dried pine wood chips, dry cedar chips, or green cedar chips) on airborne concentrations of NH3, total reduced sulfides (TRS), CO2, CH4, and N2O above lab‐scaled bedded manure packs. Four bedded packs of each bedding material were maintained for two 42‐d periods. Airborne NH3, TRS, CO2, CH4, and N2O were measured weekly. Bedded packs containing dry or green cedar had lower concentrations of NH3 (350.8 and 357.3 mg m−3, respectively; P < 0.05) than bedded packs containing pine chips or corn stover (466.0 and 516.7 mg m−3, respectively). Airborne CO2 was also lower from bedded packs containing dry and green cedar (1343.7 and 1232.3 mg m−3, respectively; P < 0.001) compared with bedded packs containing pine chips or corn stover (2000.2 and 1659.8 mg m−3, respectively). Air samples from bedded packs containing green cedar chips had a higher (P < 0.01) concentration of CH4 than bedded packs containing dry cedar chips, corn stover, or pine chips at Day 35 and 42. Initially, TRS concentration was similar among all bedding materials; at 28 to 42 d, TRS was higher (P < 0.001) from bedded packs containing the cedar products. Airborne N2O was similar (P = 0.51) for all bedding materials. Pine chips and cedar products can be adequate substitutes for corn stover in deep‐bedded barns, but cedar bedding may need to be removed more frequently.