FOR RELEASE: July 29, 1997
Contact: Blaine P. Friedlander, Jr.
Office: (607) 255-3290
Internet: [email protected]
Compuserve: Larry Bernard 72650,565
http://www.news.cornell.edu
ITHACA, N.Y. -- Growers know that after years of driving heavy farm
equipment over wet soil during the planting or harvest seasons, the soil
gets compacted. In compacted soil, crops have difficulty growing. Deep
tillage to break up compacted "hardpan" layers requires powerful tractors
that are not available to some growers and often is not an effective
long-term solution. Cornell University scientists are developing a kinder,
gentler way to rejuvenate the soil: through biological means.
On Friday, Aug. 1, officials from the U.S. Department of Agriculture and
growers from around the Northeast will tour Cornell's Homer C. Thompson
Vegetable Research Farm in Freeville, N.Y. -- one of the fields used in
testing the biological remediation of compacted soil.
"Soils vary in the susceptibility to compaction," said David Wolfe, project
coordinator and Cornell associate professor of fruit and vegetable science.
"Clay soils are very susceptible, particularly when they have low organic
matter content. Some medium-textured soils are also quite susceptible to
compaction because of interlocking among soil particles of various sizes.
"There is nothing good about compact soils," Wolfe said. "They hamper crop
growth as they restrict roots, and the plants show an increased tendency
for root disease, nutrient deficiency, pest damage and weed competition.
Compacted soils also are more prone to both flooding and drought."
The biological solutions being crafted at Cornell involve the use of
particular rotation crops that have the ability to grow deep roots into
compacted soils and produce abundant organic matter above and below ground.
"We've known that taking land out of vegetable production for several years
to grow alfalfa is pretty effective," Wolfe said, "but this is not an
option many growers can afford." Instead, the researchers have sought
alternatives that do not require taking land out of production for more
than one summer.
During the past three years of the study, the researchers have evaluated
more than a dozen different summer and winter cover crops at the Cornell
research farm and on commercial farms with grower cooperation throughout
New York. One crop that has begun to stand out from the rest of the pack
is Sudangrass. It is particularly effective at sending down deep roots to
loosen the soil when it is mowed once during the season. It also produces
an abundant amount of organic matter that fortifies the soil's microbial
community and appears to protect plant roots from parasitic soil nematodes.
The researchers also have identified some other cover crops, such as yellow
mustard, that show promise, but they have been difficult to establish in
some locations. "We still have a lot to learn about how best to grow these
crops and how best to fit them into rotations with vegetables," Wolfe said.
A follow-up research initiative currently is being developed, and will
include examining in more detail the effects of compaction on pathogenic
and beneficial microorganisms in the soil.
Wolfe is collaborating with Harold M. Van Es, Cornell associate professor
of soil, crop and atmospheric sciences; George S. Abawi, Cornell professor
of plant pathology at the Agricultural Experiment Station, Geneva, N.Y.;
Michael Glos, Cornell research technician; and Cornell Cooperative
Extension vegetable specialists Lee Stivers, Dale Riggs and Laura Pedersen.
The project is funded by USDA Hatch grants and a grant from the USDA
Sustainable Agriculture Research and Education (SARE) program.
A paper, "Growth and Yield Sensitivity of Four Vegetable Crops to Soil
Compaction," was published in the Journal of the American Society of
Horticultural Sciences (1995) by Wolfe, Daniel T. Topoleski, Cornell
graduate student; and Cornell research technicians Norman A. Gundersheim
and Betsy A. Ingall. Wolfe also prepared a brief for growers, "Soil
Compaction: Crop Response and Remediation," published through the Cornell
Department of Fruit and Vegetable Science, Report No. 63, January 1997.
-30-
RSS