Many factors contribute to this problem, but tillage is considered the primary one. Another concern is the conversion of Conservation Reserve Program (CRP) land back to agriculture production. Conversion can significantly setback soil quality and environmental benefits gained by many years in CRP. Land in CRP is generally enrolled for production and environmental reasons: row crop production can be marginal and damaging to both soil and water quality. Thus, enrollment in CRP prevents these highly erodible lands with marginal productivity from further deterioration.