(i) Vermicompost — Compost is a kind of manure which is rich in organic matter and nutrients. The compost prepared by using earthworms to hasten the process of decomposition of plants and animals refuse is called as Vermicompost.
(ii) Green manure — The manure which is prepared by decomposing green plants in the field itself is called green manure. For example — sun hemp is grown in fields, mulched by ploughing and allowed to decompose in the field for the preparation of green manure.