ADAMS CENTER — Armed with a shovel and Glad plastic bags, Michael J. Wunsch was striding back and forth across a sunny field near North Harbor Road on Tuesday, pulling up plugs of grass.
Mr. Wunsch, a graduate student from the department of plant pathology at Cornell University, Ithaca, is on the hunt for a devastating disease that has been creeping into the north county.
Brown root rot is a cold-weather disease that attacks forage crops such as alfalfa during the winter, when the plants are dormant, and can stunt or kill them. Also known as the fungus Phoma sclerotiodes, the disease causes lesions on plant roots and crowns.
On Tuesday, Mr. Wunsch began a weeklong effort to sample various grass crops across Jefferson, Lewis, St. Lawrence, Franklin, Clinton and Essex counties.
He hopes the samples, which he will spend the summer studying, will show whether the brown root rot has infected local grass fields and also will tell him which varieties are more resistant to the disease.
The goal is eventually to offer farmers a list of recommendations about what plants can survive in affected fields.
After spreading from Canada to Wyoming in 1996, the disease then spread to Idaho, Montana and Minnesota. By 2003, it had been spotted for the first time in New York when diseased plants were identified in Clinton County.
In 2005, researchers found brown lesions on alfalfa plants in Lewis and St. Lawrence counties. Brown root rot most likely has infected Jefferson County alfalfa as well, although the extent of the spread is not known.
"It's likely been here a long time," Mr. Wunsch said. "We don't have proof of that, but it's likely."
By studying perennial cool-season grasses such as orchard, brome, timothy or reed canary varieties, Mr. Wunsch hopes to understand more fully what impact the fungus has on the crops and which ones are better equipped to survive.
"It has been isolated in forage grasses, but we don't know anything about the susceptibility," Mr. Wunsch said.
Understanding the relationship between the disease and the grasses is critical, as a decline in production could have a ripple effect on the local economy, said Michael E. Hunter, field crops educator with Cornell Cooperative Extension of Jefferson County.
"Forage is so important for farmers here because you have so many animals to feed on the farms," Mr. Hunter said. "Any disease, insect or weather-related impact carries over to the farm and has a negative impact on the farm."
As the top hay producer in the state, in terms of total acres and the number of tons produced, Jefferson County is particularly susceptible, Mr. Hunter said.
Even as they try to understand the disease, teams of Cornell faculty and Extension educators have been looking at ways to cultivate disease-resistant alfalfa and forage grasses.
Mr. Wunsch is among those conducting trials with 11 different varieties at the W.H. Miner Agricultural Research Institute in Chazy and at the Cornell E.V. Baker Agricultural Research Farm in Willsboro.
With no clear answers on the most resistant varieties, the Northern New York Agricultural Development Program has been providing funding so that researchers from Cornell University and Cornell Cooperative Extension can help regional farmers recognize the disease in over-wintered alfalfa and forage grass crops.
Mr. Wunsch said local farmers should not spend too much time worrying about the disease's effects, though. He said farmers should have their crops tested for brown root rot only if there has been both significant plant death during the winter and obvious signs of brown lesions on the tap roots of the plants.
"There are many factors that cause winterkill," he said. "This is just one particular factor."
