Early Cotton Planting Requires Irrigation
Cotton growers can produce more cotton if they plant early, but not without irrigation. That’s the finding of Bill Pettigrew, a USDA–Agricultural Research Service scientist in Stoneville, Miss. He tested the performance of cotton in irrigated and nonirrigated plots, with half the plots planted early, in the first week of April, and half planted in a more traditional time, the first week of May.
Previous research indicated that planting earlier in the year increased cotton yields. This is likely because the peak blooming period shifts closer to the longest day of the year, in June, avoiding the typically drier months of the year, July and August. The additional sunlight associated with longer days also allows the plants to take in more sunlight during their growing season.
However, most of this research was done on irrigated crops. Pettigrew found that while early planting does increase yield, it does so only with irrigation. Early planting increased cotton pro-duction in two of the four years of the study with irrigation. However, the nonirrigated plots never saw increased production from early planting and even saw a 13% decrease in yield one year.
The study was conducted from 2005 to 2008, and the only year that irrigation did not increase yield was 2005, when the study area was hit by Hurricane Katrina.
Pettigrew concluded that early planting clearly needs irrigation to increase cotton yields. This implies that if Mississippi Delta producers don’t have irrigation capabilities, they should probably not adopt an early-planting strategy.
Is Your Irrigation Pump Efficient?
Pumping costs are often one of the largest single expenses in irrigated agriculture. Properly sizing pipelines to match your pump output will help minimize costs, according to analysts at the Texas Agricultural Extension Service.
There are two common methods of determining the efficiency of pumping plants. One is to measure the efficiency of each component of the plant (motor, shaft and pump). Once the efficiencies of the components are known, the overall efficiency is easily calculated. This requires specialized equipment and considerable expertise.
Another method is to calculate the load on the motor or engine and measure how much fuel is used by the power unit. The fuel usage can then be compared to a standard. The most widely used standards were developed by the agricultural engineering department of the University of Nebraska. The fuel consumption rates in the table below indicate the fuel use that can be reasonably expected from a properly engineered irrigation pumping plant in good condition. The actual fuel usage of a new or recon-ditioned plant should not be larger than that shown.
The Irrigation Show, held Dec. 5 to 7 in Phoenix, Ariz., is your opportunity to explore more than 200,000 sq. ft. of the latest equipment and services, find solutions for water management and discover strategies and skills to improve your bottom line. Increase your productivity and profitability with targeted education classes, get certified and earn CEUs for a competitive edge. Go to www.irrigationshow.org for event details.
- November 2010