Dike it to dam it
Furrow diking not only saves water – as has been proven by more than a decade of field research – but also slashes irrigation costs, says Russell Nuti of the USDA Agricultural Research Service.
Nuti and team researcher Clint Truman, both with the ARS National Peanut Research Laboratory, have been exploring the use of furrow diking in southeast states where water runoff is a problem. That team has looked at the effects of furrow diking on water needs and yields.
Furrow diking is a tillage system where soils are scooped into ridge-like barriers running alongside row crops. The ridges hold irrigation and rainwater.
Diking During A Drought
In one study run by Nuti and Truman, the researchers compared the effects of runoff and erosion in cotton fields with and without furrow diking. They used a rain simulator, which replicates rainfall amounts from past storms, and moisture meters that automatically determine the soil’s water needs.
They found that furrow diking during a moderate drought saved farmers 1 inch of irrigation water per acre, reduced runoff by 28%, and curbed soil erosion.
The next year, when drought conditions were more severe, Nuti and Truman discovered that furrow diking saved 5 inches of irrigation water per acre.
In a second study, the researchers compared crop yields, water needs, and the effects of different irrigation rates on tracts of furrow-diked cotton with traditionally tilled cotton. They found that in one of three years, growers could reduce the irrigation rate by a third and still achieve the same yield as a traditional cropping system. The difference in yields in this drought year was sufficient to pay for the practice of furrow diking for 12 years, according to Nuti.
Furrow diking has enjoyed a long history of proving itself in field tests. A Texas A&M University study, for example, projected that diking could increase yields in the High Plains by as much as $87 million a year. The equipment needed for furrow diking is relatively inexpensive and can be purchased from several manufacturers. It is also simple enough for farmers to build with materials found in most farm machinery shops. According to Texas A&M research, the equipment needed to form dikes can pay for itself in just one season with the increased yields from only 75 acres of cotton.
Furrow diking equipment was designed and tested in the mid-1970s by Bill Lyle, an agricultural engineer at the Texas A&M research center in Lubbock, Texas. Lyle also designed a plow-out attachment that’s placed in front of tractor tires to break down the dikes prior to harvest to smooth the row for harvest equipment.