Cropland area under conservation tillage

Cropland area on which tillage practices leave plant residues (at least 30-35 percent) on the soil surface for erosion control and moisture conservation. Soil should normally not be inverted but only ripped. Conservation tillage includes: i) Reduced tillage/ minimum tillage, preparing the land with equipment which does not invert the soil and which causes little compaction but which leaves some ripping lines. For this reason, the soil normally remains with a good cover of residues on the surface. Reduced tillage is usually carried out with specialized tined implement, such as a ripper. ii) Strip tillage, which involves strips being tilled to receive the seed, while the soil along the intervening bands is not disturbed and remains covered with residues such as mulch. iii) Ridge tillage, which is a system of ridges and furrows. The ridges may be narrow or wide and the furrows can be parallel to the contour lines or constructed with a slight slope, depending on whether the objective is to conserve moisture or to drain excess moisture. The surface is prepared by scraping off the top of a ridge, with the crops planted into the tops of the ridges formed during cultivation of the previous crop. The soil is covered with residue between the rows until planting. The ridges can be semi-permanent or be constructed each year, which will govern the amount of residue material that remains on the surface.