Soils & Pastures
Green manuring
Soil health degradation is one of the most important problem faced by the farmers. Due to it the land is becoming barren. �e uncontrolled use of chemical fertilizers is deteriorating the soil physical, chemical and biological properties. �erefore, to overcome this problems the concept of organic farming came into existence. �e organic farming depends on organic manures like farm yard manure, compost, green manuring etc.
�erefore, green manuring is one of the most important type of manure used in organic farming. Green manures are fertility building crops and may be broadly de ned as crops grown for the bene t of the soil. �e green manuring crops improve the humus, organic carbon, nitrogen and soil microbial growth. Green manuring can bring a number of advantages to the grower. Green manuring leads to the addition of organic matter to the soil. Green manuring crops increase the biological activity in the soil. �ese crops improve soil structure. Green manure crops helps in reducing soil erosion. �ey help to increase the supply of nutrients available to plants. �ese crops help in reducing leaching losses. It is also reported that green manuring crops help to suppress weeds, reducing pest and disease problems, providing supplementary animal forage. �us, the present study indicates the type and importance of green manuring on plant growth.
Green leaf manuring Where the application of green leaves and twigs
of trees, shrubs and herbs collected from plants grown in wastelands, eld bunds, degraded lands and nearby forest. �ey are turned down or mixed into the soil 15-30 days before sowing of the crops depending on the tenderness of the foliage or plant parts is known as green leaf manuring.
In situ green manuring
In situ green manuring is also called as On – farm green manure or legume green manuring. In this system, the short duration legume crops are grown and buried in the same site when they attain the age of 60-80 days a�er sowing. �is system of on-site nutrient resource generation is most prevalent in northern and southern parts of India, where rice is the major crop in the existing cropping systems. Almost any crop can be used for green manuring, but legumes are preferred because of their ability to x nitrogen from the air. Green manuring with legumes( peas, clovers, lentils, etc.) is called legume green manuring. �ese crops should be turned into the soil before setting of seeds. Legume green manuring could be pro tably used on lands where, it was not possible to add animal manures.
Here are some of the bene ts of Green Manure Greater soil fertility
Green manures recycle nutrients and add organic matter to the soil. �ey help prevent nutrients being washed out of the soil. �e
nutrients are taken up by the green manure and held inside the plant. When the nutrients are needed for the next crop the plants are dug into the soil or used as a mulch on top of the soil. �is helps to increase crop yields. Legumes and other nitrogen xing plants which take nitrogen from the air to the soil are particularly bene cial. Improved soil structure Green manures improve soil structure, letting more air into the soil and improving drainage. Green manures help sandy soil hold more water and not drain so quickly. Prevention of soil erosion Green manures help to stop the soil being carried away by wind and rain. �e roots penetrate the soil and hold it in place.
Weed control
Green manures help to control weeds. Bare soil can become quickly overgrown with weeds which can be difficult to remove. Green manures cover the ground well and stop weeds growing beneath them, by competing for nutrients, space and light. �erefore, it can be concluded that green manures improve soil structure, letting more air into the soil and improving drainage. Organic matter helps sandy soil hold more water and not drain so quickly as a result of increased aggregate stability and porosity. Also organic matter reduces rate of runoff and soil erosion. Change in chemical property of soil could be clearly observed. Leguminous green manure crop in soil increases nitrogen level by xation.
January- February 2017
FARMERS
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