A catch crop planted, esp. in orchards. as a protection to the soil in winter, as well as for the benefit of the soil when plowed under in spring.
A crop, such as clover, planted between periods of regular crop production to control weeds, prevent soil erosion and provide humus or nitrogen to the soil.
A close-growing crop, planted primarily as a rotation between regularly planted crops or to reduce weed pressures before the regular crop emerges, that protects soil from erosion and improves it between periods of regular crops.