manuring

Manuring is the agronomic practice of applying livestock manure to agricultural land to supply nutrients, improve soil organic matter, and recycle waste. Manure can be applied as solid manure (e.g., cow, horse, or pig dung mixed with bedding) or as a liquid or slurry (often called slurry or manure slurry).

Nutrient content varies by source, but manure generally contains nitrogen, phosphorus, and potassium, along with micronutrients and substantial organic matter. When applied to soil, it supplies readily available nutrients and supports soil structure and microbial activity. Unlike synthetic fertilizer, it is a slow-release source whose nutrients become available over time as it decomposes.

Application methods include surface spreading, incorporation into the soil, or injection for slurry. Timing depends on crop needs and weather; avoid spreading on frozen, waterlogged, or windy days and limit near harvest to minimize losses. Rates are guided by soil tests and nutrient management plans to prevent over- or under-application.

Types include farmyard manure (solid manure from cattle, horses, sheep, or goats), slurry or liquid manure (from dairy, beef, pig operations), and specialized manures such as poultry litter. Manure can be composted to reduce odors and pathogens before use.

Environmental concerns include ammonia volatilization, nitrate leaching to groundwater, phosphorus runoff to surface water, and greenhouse gas emissions. Best practices include proper storage, timely application, incorporation or injection, buffer strips, and adherence to regulatory nutrient-management requirements.