This will be important in the region as rapid industrial development will or is already competing for labor and water. These increases in productivity have the potential to reduce the need for US rice exports. However, many farmers around the world have overcome the challenges of no-till on the more difficult soils which are poorly drained or have a tendency to crust, set and compact. For example, on the fragile subtropical soils of Brazil, five to six tons of residue or crop cover all year round is essential for the control of erosion and for crop germination. Winter cover crops such as black oats and winter legumes or a late summer second crop such as sorghum or pearl millet have secured the germination of spring planted crops such as soybeans and maize by providing adequate residue cover in the spring to protect the soil from the crusting impact of heavy rain.
Soil compaction can be a severe limiting factor on soils high in low-activity clays.
In areas with reasonable rainfall, such as Maringa, Brazil, a deep rooted winter cover crop such as black oats has made no-till soybeans and maize possible on these soils. In the U.S. cool wet springs have impacted germination and growth of no-till corn on poorly drained soils. The surface residue keeps the soil cool longer. Many farmers continue to no-till soybeans but have returned to tillage for corn. However, other persistent farmers have found a solution to this problem.