Efficacy of different additives in ensiling faba bean and field pea based whole crop silages
Mixed stands of faba bean + wheat (FBW; faba bean 0.84), and pea + wheat (PW; field pea 0.89 on dry matter [DM] basis) were harvested in Siikajoki, Finland. The crops were ensiled in triplicate in laboratory silos using four additive treatments: control without additive, two commercial lactic acid bacteria stains (LAB) and ACID (formic and propionic acids). Ensiling time was 105 days. The crops contained 173 and 181 g DM kg-1 and the water soluble carbohydrate (WSC) concentration was 156 and 176 g kg-1 DM in FBW and PW, respectively. ACID restricted silage fermentation in FBW (WSC 146; fermentation products 43 g kg-1 DM). The other silages had high concentration of fermentation products (180–204) and low WSC concentration (< 22 g kg-1 DM). The volatile fatty acid concentration was below 30 g kg-1 DM in all treatments. PW-ACID treatment resulted in higher ethanol concentration and better aerobic stability (>235 hours) compared to control or LAB silages. When ensiling wet legume whole crops effluent losses, extensive fermentation and poor aerobic stability may cause problems.