Question

Define green manure. Give one example.

Answer 1

Hint: Manure of plant origin that improves soil structure and soil fertility. They provide organic matter and nutrients by decomposing plant residues.

Complete answer: When green undecomposed plant residues are used as manure then, it is known as green manure.
It can be produced in two ways- first by growing crops for green crops and second is by collecting plant residues from wastelands, fields, and forests. Most of the plants used for green manure belong to the family of leguminous plants.
The plants that are used for green manure are known as green manure crops.
The most common crops are Sesbania rostrata, Cowpea, Crotalaria juncea, Cluster bean, and Sesbania aculeata. They help in biomass accumulation and nitrogen fixation.

Additional information: Green manure increases soil fertility and structure by improving its water holding capacity. It also prevents soil loss from erosion.
The off-season growing of green manure crops prevents weed growth and proliferation.
It helps in the reclamation of alkaline soils and can control root-knot nematodes.

Note: Green manures are incorporated back in the soil either by removal and decomposing. They help in nutrient accumulation and prevent leaching of soluble nutrients from the soil. They help in bringing nutrients required for crop growth from the lower soil layers to upper soil layers.
They provide ground cover and prevent damage to the soil structure.