Farmyard manure, a valuable resource for enriching soil fertility and enhancing crop productivity, needs 6 to 12 months to decompose before being spread on fields. The effect of composting farmyard manure (in other words allowing it to sit in a pile or midden) enables the breakdown of organic matter into nutrient-rich humus, offering numerous benefits to soil health and plant growth.
Here are five compelling reasons why farmyard manure needs time to decompose before being used.
Nutrient Stabilisation: Fresh farmyard manure contains elevated levels of nitrogen, phosphorus, potassium, and other essential nutrients crucial for plant growth. However, these nutrients are not immediately available to plants in their raw state.
Decomposition processes during composting break down complex organic molecules into simpler forms that plants can readily absorb.
Allowing farmyard manure to decompose over time stabilises nutrients, ensuring a more balanced and sustained release of essential elements to crops.
Reduction of Phytotoxicity: Fresh manure, particularly from livestock, can be phytotoxic to plants due to its high ammonia content.
When applied directly to fields, fresh manure can “burn” plant roots and foliage, leading to stunted growth or crop damage. Composting farmyard manure facilitates the conversion of ammonia into stable forms of nitrogen, reducing the risk of phytotoxicity.
This process helps create a safer and more beneficial environment for crops to thrive.
Weed Seed Sterilisation: Farmyard manure may contain weed seeds from consumed plants or from hay and straw bedding used in livestock pens.
Without proper composting, these weed seeds can survive and germinate when manure is spread onto fields, leading to increased weed infestation and competition with crops.
Allowing farmyard manure to decompose over time under controlled composting conditions helps sterilise weed seeds, minimising the risk of weed proliferation in agricultural fields.
Pathogen Elimination: Fresh manure can harbour harmful pathogens such as bacteria, fungi, and parasites, posing a risk to both plant and human health. Pathogens present in untreated manure can contaminate crops, water sources, and food products, causing diseases and foodborne illnesses.
Through the composting process, elevated temperatures and microbial activity help eliminate or suppress pathogens, making the resulting compost safer for agricultural use.
Properly decomposed farmyard manure reduces the likelihood of pathogen transmission and promotes overall farm hygiene and biosecurity.
Odour Reduction and Aesthetics: Fresh farmyard manure emits strong odours characteristic of decomposing organic matter, which can be unpleasant for farmers, nearby residents, and livestock.
Composting farmyard manure reduces offensive odours by promoting aerobic decomposition and microbial activity, leading to the production of stable organic matter with a more earthy aroma.
Additionally, composted manure has a finer texture and uniform appearance compared to fresh manure, making it easier to handle, store, and apply to fields without causing aesthetic concerns.
Allowing farmyard manure to decompose through composting is essential for optimising its nutrient value, and minimising risks associated with phytotoxicity, weed infestation, pathogen contamination, and offensive odours. Composted manure serves as a sustainable and environmentally friendly soil amendment, promoting healthy soil ecosystems and robust crop yields in agricultural systems.
