October 27, 2013

Going green in winter

Peter Hagar, Agriculture Educator

— Concerns about agricultural impacts on the environment continue to be a hot topic both here and across the lake.

Like any human activity, agriculture does indeed have effects on the environment; some good, some bad. With modern farms getting bigger, there are both concerns and opportunities to be addressed with respect to environmental impacts.

And with the increased consumer interest in agricultural practices and how food is produced, farmers will need to consider new and old practices to meet this challenge.

When an annual crop such as corn or soybeans is harvested, it often leaves the soil exposed and unprotected. While corn harvested for grain often leaves considerable residue, corn silage is made by chopping the entire plant, leaving only stubble and bare soil.

The benefit of plant residue on the surface is that it intercepts precipitation and reduces erosion of the topsoil. This exposed soil problem is compounded by the fact that farmers often spread manure after harvest to empty their storage facilities for the long winter.

While the nutrients are mostly absorbed and stored in the soil, there is the potential for erosion and surface water runoff as well as leaching into the water table. One beneficial conservation practice that has been long known about but slow to gain acceptance in the North Country is the use of cover crops following annual crops such as corn.

This year, however, a program funded by the USDA’s Natural Resources Conservation Services has led to a significant increase in the use of cover crops in Clinton County. In the 2007 Ag Census, Clinton County was estimated to have 24,000 acres planted to corn. With funding from the America’s Great Outdoors Initiative, more than 1,700 acres were covered this year with winter rye, a cereal-grain cover crop that grows late into the fall, goes dormant and then resumes growing in early spring.

Building on an effort that began last year in Vermont, the seed was broadcast onto the fields early this month by a specially modified helicopter. Seed was spread over both standing corn and fields that were already harvested. Winter rye is popular as a cover crop because of its ease of establishment.

With enough moisture, rye seed will sprout and establish just sitting on the soil surface. After several rainy days and mild weather, observations earlier this week were very promising.

Cover crops such as winter rye help to prevent soil erosion, retain nutrients and improve soil health in several ways. Winter rye in particular is a very effective scavenger of nutrients, especially Nitrogen. By utilizing nitrogen from fertilizer or manure that remains in the soil following the corn harvest, a valuable nutrient is preserved in organic form until next spring.

When the cover crop is terminated by herbicide or tillage in the spring, these nutrients are released to be utilized by the subsequent crop. Research has shown that winter rye’s quick-growing, fibrous root system can take up and hold as much as 100 lbs. of nitrogen until spring.

Cover crops are also beneficial because they reduce erosion, add organic matter to the soil and improve soil health. Keeping a growing plant in the soil reduces erosion from wind and rain, adds organic matter when it is later plowed under and helps reduce compaction from heavy equipment.

Some cover crops also have the added benefit of being harvested in the spring for additional feed. With the ability to plant directly into corn stubble right after harvest without additional tillage, a winter rye cover crop can be established up until Oct. 15.

Because of our proximity to Lake Champlain and the many farms along its shores, Cornell Cooperative Extension, in collaboration with the Lake Champlain Basin Program and the Clinton County Soil & Water District, held a series of on-farm meetings over the course of the summer to highlight lake-friendly farming practices and best-management practices for the reduction of non-point-source pollution.

Our last meeting of the “Farming in the Basin” series will be held at 1 p.m. on Nov. 8 at Miner Institute in Chazy. After a presentation by Dr. Kitty O’Neil, regional extension crop specialist, we will visit several fields that participated in the aerial seeding program. We encourage all interested farmers, landowners and others to come and learn more about how farmers and local, regional and federal agencies are all collaborating to reduce agricultural non-point source pollution in the Champlain Valley.

For more information and to register, contact Peter Hagar, CCE Clinton County, at 561-7450 or