Reduced Tillage for Cotton in Irrigated Desert Southwest

Reducing tillage has become necessary in the irrigated desert southwest of the United States. This is mainly due to soil quality deterioration and intense environmental degradation from soil erosion by wind after conventional tillage operations. Soil erosion by wind is very common during the spring, when the fields are without vegetation cover and have been intensively tilled, ready for planting. A study was conducted to evaluate the performance of upland cotton under different tillage systems, in the irrigated desert southwest of the United States. No tillage and strip tillage treatments were compared to the conventional plow-till treatment for cotton growth and yield. A winter wheat cover crop was initially planted during the fall preceding cotton. The cover crop was terminated by mowing to about 10 inches tall stubble and the field was allowed to dry down. Tillage treatments were established in the wheat stubble and a round-up ready cotton (PHY 499 WRF) was planted in May 2016. First glyphosate application was applied at planting for weed control. A second application took place at about 6 weeks after planting. Midseason results show that there were no significant differences in plant height, number of nodes, number of squares and number of bolls among the treatments. Yield and fiber quality results will be presented at the end of the season.