UNIVERSITY PARK, Pa. -- Last summer it was drought in Pennsylvania; this summer it is too much rain. "It just goes to show," as the late Gilda Radnor's unforgettable character on Saturday Night Live -- Rosanne Rosannadana -- often said, "It's always somethin'."

But it's no laughing matter, according to tree experts in Penn State's College of Agricultural Sciences, who say that the frequent and heavy rainfall and cool temperatures this spring and summer have been as damaging to trees as last summer's drought conditions. The dampness has promoted anthracnose -- a fungus that affects trees such as maple, dogwood, ash, white oak and sycamore -- across Pennsylvania. And lots of people have noticed.

"Some sycamores have lost up to 90 percent of their leaves this summer," says John Holowid, Penn State Cooperative Extension agent in Erie County. "Trees affected with anthracnose have brown and shriveled leaves that may progressively die and drop off. Though unsightly, the fungus does not tend to kill trees."

There are outbreaks of anthracnose in Pennsylvania every year we have a wet spring, notes Don Davis, professor of plant pathology. But this summer, trees are severely stressed. "Many sycamores had their leaves turn brown and fall, grew a second set of leaves that also died, and are now releafing for the third time," he says. "Anthracnose is worse this year than I can ever remember."

Many trees in southern counties are refoliating, but trees in the northern half of the state have not fared as well and may not grow new leaves until next year. Still, according to Jim Finley, professor of forest resources, most will survive. "We have gotten a lot of calls about it," he says. "When folks saw so many oak trees losing their leaves in the northwest region of the state, they were a bit unnerved. But trees are going to recover. "It has been a great growing season. Most of the oaks are releafing," Finley adds. "The rain that caused this fungus outbreak is sort of a double-edged sword. Trees are well hydrated because of the high levels of soil moisture, so they are healthy and will bounce back. It would be worse if drought immediately follows the fungus stress."

Penn State experts are urging property owners not to give up on their trees. "Just because there are no leaves on it doesn't mean it's dead," says Finley.

Anthracnose symptoms appear in early spring when fungal spores infect leaf buds. If conditions continue to be favorable for the spread of the fungus, as they have been this year, symptoms persist and worsen in late spring and early summer. Trees infected with anthracnose for consecutive years will weaken and become vulnerable to pests and other diseases.

This year's cool, damp weather has had far-reaching effects. Anthracnose has damaged trees in Michigan and Ohio as well as Pennsylvania. Davis reports seeing trees affected by anthracnose as far south as the mountains of the Carolinas. "We see it all over the eastern United States," he says. "Every time we have a cold, wet spring, there are outbreaks, and the colder and wetter the weather is, the worse anthracnose is."

Some experts advise property owners to fertilize their trees in the fall after an outbreak of anthracnose, but Davis doesn't think that helps much. "It's a feel-good remedy," he says. "Folks want to do something for their trees and it never hurts to fertilize in the fall, but truly there isn't much we can do. The trees look really bad now, but they'll come back and be just fine."

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EDITORS: Contact Don Davis at 814-865-1689, Jim Finley at 814-863-0401 or John Holowid at 814-825-0900.

Contact:

Jeff Mulhollem jjm29@psu.edu 814-863-2719 814-863-9877 fax #215