NOVELTY - Composting and returning of crop straws, involves choosing the corner of field parcel, digging a pit, stacking a part of dug soil around pit, treading down as pit ridge, and stacking other part aside the pit ridge for covering straws after straws are stacked; stacking crop straws in pit layer by layer, treading down every layer, spreading straw composting agent and urea; sealing the stack top by soil/weeds/rapeseed shells; and after few months of composting and crops are harvested, digging decayed straws out of pit and spreading in field as base fertilizer, then turning over field parcel.    USE - For composting and returning of crop straws (claimed) which is used for animal feed.    ADVANTAGE - The use of fertilizer makes the hardened land soft. The method saves the fertilizer cost expense of farming by farmers; reduces the fertilizer dosage and reduces the production cost; and reduces the problem of environment pollution brought by straw burning. The crop straws increase the soil organic matter and nutrient content; improve soil physical performance and increase soil permeability; and reduce pressure for land.    DETAILED DESCRIPTION - Composting and returning of crop straws, involves choosing the corner of a field parcel, digging a pit, stacking a part of the dug soil around the pit, treading down as a pit ridge, and stacking the other part aside the pit ridge for covering straws after the straws are stacked; stacking crop straws in the pit layer by layer, treading down every layer, uniformly spreading straw composting agent (1-2.5 kg/mu) and urea (1.5-3.5 kg/mu), keeping the thickness of every layer after being treaded down gradually decreased from bottom to top; after the straw stacking is finished, uniformly sealing the stack top by soil or weeds or rapeseed shells, and controlling the thickness of the covering object to be 4-6 cm; and after a few months of composting and the next season of crops are harvested, digging the decayed straws out of the pit and uniformly spreading in the field as a base fertilizer, then turning over the field parcel.