By Paul Huggins
Staff Writer
Decatur Daily
Decatur, Alabama
The hybrid American chestnuts now being planted in American forests may be strong enough to resist the disease that once devastated the species, but threats still lurk in the woods that make their survival a question.
Research at Bankhead National Forest, however, may provide answers that will ensure the trees’ return as the “mighty giants” of eastern America.
“We found out a couple of things,” said Stacy Clark, Ph.D. researcher for the U.S. Forest Service’s Southern Research Station, who planted 250 chestnut seedlings in Bankhead in March 2007.
Fast but vulnerable
“These trees can grow pretty fast in the field. They’re probably one of the fastest-growing species out there.
“However, they’re extremely susceptible to different things when they’re first planted,” she said. “A lot of them died that first year because they couldn’t withstand the drought. And some of them have had some insect defoliation. And then the deer have nibbled on them.”
About 100 have died so far, Clark said.
Learning about those challenges is why the forest service and The American Chestnut Foundation initiated the Bankhead study and additional studies in three more national forests.
The findings will help prepare a management plan for when the chestnut foundation provides the forest service with thousands of trees to plant each year, Clark said.
A century ago, the American chestnut was one of the most important trees in eastern forests. Wild animals and livestock feasted on the nutritious nuts, which also produced a cash crop for rural Appalachian families.
Chestnuts also were one of the best trees for timber because they grew straight and tall and resisted rot.
But a fungus, accidentally imported from Asian chestnut trees in the early part of the 20th century, spread quickly, killing all major stands by the 1950s. The species that routinely reached 100 feet now grows to little more than a 5-foot shrub before dying from the fungus.
A hybrid chestnut, crossed with an Asian variety, showed it can withstand the fungus under closely managed, nursery conditions. Researches now must learn whether it can survive in the wild.
Clark, who started the Bankhead research while based at Alabama A&M University, said it appears the trees, at least while young, will need ongoing management.
“If you just go out there and plant the trees and walk away, you’re pretty much going to have mass failure,” she said. “So you may have to spray insecticide on them, you may have to cut down natural competitors around them, maybe use herbicide.”
Many of the chestnuts at Bankhead were expected to fail, Clark added, because they were either the pure American variety with no blight resistance or strains of hybrids with mixed levels of blight resistance.
About 1,200 chestnuts planted last year in Tennessee, North Carolina and Virginia are more blight-resistant than the Bankhead trees and have received maintenance assistance, such as deer guards. Those trees show a 90 percent survival rate heading into their second year, said Clark, now monitoring chestnut progress from the University of Tennessee.
Providing enough management for restoring chestnuts throughout eastern America will be a tall task, Clark said. There is talk of building a volunteer network to help maintain the chestnut seedlings, but she said she’s not optimistic volunteers will be effective.
“There are a lot of nuances to taking care of trees in the field,” Clark said. “If you have volunteers you’re going to have to do a lot of training. The forest service, in my opinion, is going to have to put some resources into chestnut restoration.”
Despite the challenges ahead, Clark said, she
is optimistic that the chestnut restoration program will prove fruitful one day, but the trees probably won’t be self-sustaining for two more generations of Americans.
“It’s probably going to be in our grandchildren’s lifetime,” she said.
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