Organic matter inputs for pasture amendment

Organic amendments like manure and compost improve soil health in prairies by enhancing structure, cation exchange capacity, and nutrient supply through microbial mineralization. Autumn application leverages winter moisture for better penetration. Horse manure compost, rich in N, P, K, Ca, and Mg, provides 78 kg/ha N, 55.5 kg/ha P, 118.5 kg/ha K, 181.5 kg/ha Ca, and 24 kg/ha Mg at 15 tons/ha. It is odorless, pathogen-free, and safe for grazing within three weeks. Raw manure has higher dry matter and organic content (pH 7.6–8, C/N 17.7–37.2); composted material has lower C/N (14–18) and stable humus. Effective composting requires balanced C/N ratios and moisture. Recommended application rates sustain 6 tons/ha dry matter production. Source: 2023 expert document 'Préparer les prairies pour l'hiver'.