story to find out more.
Farmer Alvin Kunugi
(left) and soil scientists Jorge Delgado (center) and Ronald Follett evaluate
quality and size of potatoes harvested from a rotation that included
Delgado (left) and
soil scientist Alan Stuebe of USDA's National Resources Conservation Service
study soil profile characteristics important to understanding movement and
dynamics of nitrogen. Click an image for more information about
Improving Conservation in Potato Fields
McGinnis May 9, 2006
Deep-rooted cover crops can help potato farmers prevent erosion and
protect groundwater by reducing nitrate leaching. Thats one conclusion of
Agricultural Research Service (ARS)
scientists who developed several important tools and techniques to help growers
manage their land economically and responsibly.
Heavily fertilized crops with shallow roots, like potatoes, are more
susceptible to nitrate leaching, according to
Delgado, a soil scientist in the ARS
Plant Nutrient Research Unit at Fort Collins, Colo. However, nitrogen
recovery can be significantly improvedand leaching minimizedby
using a deep-rooted cover crop like winter rye, malting barley or winter
Deep-rooted cover crops reduce wind erosion, sequester carbon, cycle
nutrients and draw nitrate further from the soil than crops with shallow roots.
Crops like winter cover rye and wheat can even be used for grazing.
Complementary potato research is being conducted in ARS labs at
In Prosser, scientists measured how much nitrogen Brassica
cover crops contributed to the soil and how much was taken up by subsequent
potato crops. Those studies found that about 30 percent of the nitrogen on the
surface of the crop field was cycled back to the soil. Planting Brassica
cover crops could save growers $15 to $20 per acre at current fertilizer
Orono researchers modeled the influence of temperature on crop residue
decomposition and nitrogen availability in order to predict the best time to
apply additional fertilizer to meet the crops needs and potentially
reduce the amount of nitrate lost to groundwater.
These efforts promote precision conservation, or
management practices that incorporate elements of conservation and precision
more about the research in the May 2006 issue of Agricultural
ARS is the U.S. Department of
Agricultures principal scientific research agency.