It Pays to Furrow Dike
O'Brien June 4, 2009
Furrow diking not only saves water, but reduces irrigation costs to a
point where it makes economic sense, according to
Agricultural Research Service (ARS)
Furrow diking is a tillage system where soils are plowed into
ridge-like barriers running alongside row crops. The ridges hold irrigation and
rain water, allowing it to soak into the soil instead of washing away.
Nuti at the ARS
Peanut Research Laboratory in Dawson, Ga., is exploring the use of furrow
diking in the Southeastern United States, where runoff is a problem and water
is a valued commodity. Farmers in the Southeast must irrigate to supplement
rainfall, but reducing runoff would reduce the need for irrigation.
Truman, a soil scientist at the ARS
Watershed Research Laboratory in Tifton, Ga., took two approaches to assess
the effects of furrow diking on water needs and crop yields.
In one study, they compared the effects on 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
an inch of irrigation water per acre, reduced runoff by 28 percent and curbed
soil erosion. The next year, when drought conditions were more severe, it saved
five inches of irrigation water per acre.
In a second study they compared crop yields, water needs and the
effects of different irrigation rates on tracts of furrow-diked cotton with
traditionally tilled cotton. There, they found that in one of three years,
growers could reduce the irrigation rate by one-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.
The findings are being published in
ARS is the principal intramural scientific research agency of the
U.S. Department of Agriculture.