Blue mold poses threat to tobacco crop

LOUISVILLE, Ky. -- Blue mold, a fungal disease that damages tobacco, has spread through a wet, gray summer and poses a threat to burley fields across Kentucky, a crop expert said Tuesday.

The entire state -- the nation's top burley producer -- is under a blue mold warning or watch, and the threat is the worst since 1996, when the disease caused about $200 million in damage, said Bill Nesmith, a University of Kentucky plant pathologist.

"We have a very threatening level of disease that is quite capable of causing economic damage on every farm in the state because we do not know where those spores will blow tomorrow," Nesmith said.

Airborne spores

Blue mold is spread across long distances by airborne spores. The disease can occur sporadically. An infected tobacco patch might be near a second field that is spared entirely.

It is too early to predict losses from this year's outbreak. Even if the disease becomes as widespread as in 1996, losses would be smaller because of deep production cuts.

Blue mold disease thrives in damp, overcast conditions. Cool, foggy nights have been the "major driver of the epidemic," Nesmith said.

Mild cases cause spotting on leaves, but the fungus can penetrate the stem and choke off the flow of water and nutrients to the plant.

Perhaps hardest-hit is the Bluegrass region of central Kentucky, which has the leading burley-producing counties.

Wet spring

William Fritz, a longtime tobacco grower in Harrison County, said blue mold has infected parts of his burley fields but he doubted it had hampered yields so far.

"It's not really as bad as you would think it would be for the weather conditions we're having right now," he said.

Fritz said he has heard of more serious outbreaks on other farms in the area. He said tobacco planted later because of the wet spring is more susceptible to blue mold.

As soon as he spotted blue mold, Fritz spread a fungicide to protect his crop. He plans a second application once the weather turns dry.

Nesmith said farmers need to aggressively curb the blue mold threat, not only for their own tobacco patches but for the sake of other growers.

Disillusionment among some growers is affecting how they react to the blue mold threat, Nesmith said. He said some county extension agents refer to it as operating in a "buyout mentality," referring to a proposal in Congress to pay growers to quit growing leaf.

"Some of their short-term decisions relative to reacting to disease control are not the best, and they are just attempting to ride it out," Nesmith said.

They need to realize that "what happens on their farm serves as spores for the community at large," he said.