Update:
Tillage and water management practices are important factor of soybean production. Water logging has potential to cause yield loss, so installing subsurface tile drainage is a common proactive. Under high clay soils, tile drainage also offers the opportunity to follow conservation tillage practices. Integration of tile drainage and no-tillage practices can improve soil health and soybean yield. Extent of tile benefit depends on its design, depth of tile and spacing in between tile.
We are conducting an on farm long-term experiment to determine the effects of (i) tile drainage and tillage interactions and (ii) tile depth and spacing combinations on soybean production. This experiment is located at Ron Holiday farm near Casselton, ND. For the first objective, tillage practices, (i) chisel (CH), (ii) strip-tillage (ST), and (iii) no tillage (NT), are compared for soybean production under only surface-drainage condition (check), open tile and control-tile drained conditions.
In 2016, strip till under open-tile drained treatment had the lowest yield of 51.84 Bu/ac and chisel till under control-tile drained treatment had the highest yield of 58.60 Bu/ac. Tillage shows significant effect on soybean yield, chisel till produced the highest yield followed by no till and strip till. In addition, control tile was superior over surface drainage and open tile in terms of soybean yield.
For the second objective, combination of three tile spacing, 30-, 40-, and 50-feet and two tile depths, 3 feet and 4 feet, are evaluated for soybean production. In 2016 growing season, the highest soybean yield of 57.5 Bu/ac was found under surface drained and the lowest yield of 42.8 Bu/ac was observed under 40 feet spacing and 3 feet depth. For 2016 growing season, tile had no effect on soybean yield indicating benefit of tile depends on rainfall intensity and distribution.
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Executive Summary
Soil and Water Management for soybean production under Fargo Clay
Principal Investigators: Dr. A. Chatterjee, Dr. A. Daigh, Soil Science, NDSU
Tillage and water management practices are critical factors of soybean production. Water logging has potential to cause yield loss, so installing subsurface tile drainage is a common proactive. Under high clay soils, tile drainage also offers the opportunity to follow conservation tillage practices. Integration of tile drainage and no-tillage practices can improve soil health and soybean yield. The extent of tile benefit depends on its design, depth of tile and spacing in between tile lines.
We are conducting an on-farm long-term experiment to determine the effects of (i) tile drainage and tillage interactions and (ii) tile depth and spacing combinations on soybean production. This experiment is located at Ron Holiday farm near Casselton, ND. For the first objective, tillage practices, (i) chisel (CH), (ii) Strip-tillage (ST), and (iii) no tillage (NT), are compared for soybean production under only surface-drainage condition (check), open tile and control-tile drained conditions.
In 2016, Strip-till under open-tile drained treatment had the lowest yield of 51.84 Bu/ac and chisel till under control-tile drained treatment had the highest yield of 58.60 Bu/ac (Figure 1). Tillage showed a significant effect on soybean yield, chisel till produced the highest yield followed by no-till and strip till. Also, control tile was superior over surface drainage and open tile regarding soybean yield.
For the second objective, a combination of three-tile spacing, 30-, 40-, and 50-feet and two tile depths, 3 feet and 4 feet, are evaluated for soybean production. In 2016 growing season, the highest soybean yield of 57.5 Bu/ac was found under the surface drained, and the lowest yield of 42.8 Bu/ac was observed under 40 feet spacing and 3 feet depth (Figure 2). For 2016 growing season, tile had no effect on soybean yield indicating the benefit of tile depends on rainfall intensity and distribution.