Farmyard Manure and Compost: Properties and Preparation

Organic manures are essential for maintaining soil fertility, improving soil structure, and ensuring sustainable agricultural productivity. Among the most widely used organic fertilizers are Farmyard Manure (FYM) and Compost. Both play a crucial role in nutrient cycling and enhancing the biological health of the soil.

Farmyard Manure (FYM)

Farmyard manure is the decomposed mixture of dung and urine of farm animals along with litter and left-over material from roughages or fodder fed to the cattle.

Properties of FYM

• Nutrient Content: FYM is a bulky organic manure. On average, well-rotted FYM contains 0.5% Nitrogen (N), 0.2% Phosphorus (P2O5), and 0.5% Potassium (K2O).
• Soil Conditioning: It improves the physical properties of the soil by increasing water-holding capacity, aeration, and soil aggregation.
• Microbial Activity: It acts as a source of energy for soil microorganisms, promoting a healthy soil ecosystem.
• Availability: Nutrients in FYM are released slowly, providing a steady supply of minerals to crops over the growing season.

Method of Preparation

The quality of FYM depends heavily on the method of storage. The most recommended method is the Trench Method:

• Trench Construction: Dig a trench about 6 to 8 meters long, 2 meters wide, and 1 meter deep.
• Layering: Place the daily collection of animal waste, urine-soaked litter, and fodder leftovers into the trench.
• Compaction: Each layer should be pressed down to ensure uniform decomposition.
• Moisture: Maintain adequate moisture by sprinkling water if the heap becomes too dry, but avoid excessive waterlogging.
• Closing: Once the trench is filled, plaster the top with a layer of soil or cow dung slurry to prevent nutrient loss through volatilization and protect it from weather elements.
• Maturation: The manure is usually ready for application after 3 to 4 months of decomposition.

Compost

Compost is a mass of rotted organic matter made from waste plant residues and animal wastes through a biological process of decomposition.

Properties of Compost

• Nutrient Density: The nutrient content of compost depends on the raw materials used. Generally, it contains 0.751% Nitrogen, 0.40.8% Phosphorus, and 0.51% Potassium.
• Humus Formation: Compost is rich in humic acids, which help in the chelation of metal ions, making nutrients more available to plants.
• Disease Suppression: High-quality compost introduces beneficial microbes into the soil that can suppress certain soil-borne pathogens.
• Carbon-Nitrogen Ratio: A well-composted product should have a C:N ratio of approximately 10:1 to 15:1 for optimal soil integration.

Method of Preparation

The most common and effective technique is the Indore Method (or Pit Method):

• Selection of Site: Select a high, well-drained area away from water sources to avoid leachate contamination.
• Material Gathering: Gather agricultural waste (straw, stalks, leaves) and mix it with animal waste (cow dung slurry) and a small amount of wood ash or lime to balance pH.
• Layering: Create layers in the pit. Place a base layer of dry organic waste, followed by a layer of animal waste, and a thin layer of soil or old compost to act as an inoculum.
• Aeration: The pile should be turned or aerated periodically (after 15 days, then after 30 days) to facilitate aerobic decomposition.
• Decomposition: Aerobic bacteria break down the cellulose and lignin in the plant materials. The pile generates heat, which helps in killing weed seeds and pathogens.
• Completion: The process is complete when the material turns into a dark, crumbly, earthy-smelling substance, typically after 3 to 4 months.

Conclusion

Both farmyard manure and compost are invaluable assets to modern agriculture. By converting farm waste into nutrient-rich fertilizers, farmers can reduce their reliance on synthetic chemicals, lower production costs, and ensure the long-term fertility of their land. Proper management of these materials is the key to optimizing their efficacy and ensuring a productive agricultural environment.