Chapter 13

Manure and Compost

(book excerpts)

Applying animal manure and compost to the soil is a long-standing practice for farmers across the world. Animal manures and animal manure-based composts significantly improve the soil’s capacity to store and supply essential nutrients (such as nitrogen, phosphorus, potassium, calcium, and magnesium), and to retain toxic elements. It allows the soil to cope with changes in soil acidity, and helps soil minerals to decompose faster. Manure and compost cause soil to clump and form soil aggregates, which improves soil structure. With better soil structure, permeability improves, in turn improving the soil's ability to take up and hold water. Greater aggregate stability can increase water infiltration rates and result in reduced potential for water, soil, and nutrients to erode. Manure and compost enhance the biological diversity and activity in the soil. As their levels increase, microbial activity tends to increase. Manure and compost are a primary source of carbon which gives energy and nutrients to soil organisms. Capturing carbon in the soil also lowers emissions of carbon dioxide to the atmosphere, and this mitigates climate change. The proportions of plant nutrients in manures and composts are usually different from what plants require for growth. In particular, these materials often contain more phosphorus than nitrogen. Animal manures harbor pathogens harmful to humans when they consume crops contaminated with soil, and under certain conditions, they can be taken up into plant tissue. The risk from pathogens is greatly reduced when manure is composted correctly.

Click on the following topics for more information on manure and compost.

Topics Within This Chapter:

  • Manure
  • Manure Nutrient Content
  • Nitrogen
  • Phosphorus
  • Potassium
  • Manure Analysis
  • Rate of Manure Application
  • Time of Manure Application
  • 120 Day Pre-Harvest Interval
  • Environmental Guidelines
  • Manure Application Methods
  • Dragline System
  • Broadcasting
  • Direct Injection
  • Compost
  • Compost Nutrient Content
  • Compost and High-Value Crops
  • Cover Crops as an Alternative