Squirrels aren’t the only ones collecting nuts this autumn. Volunteers with Virginia’s American Chestnut Restoration project are gathering them to breed the next generation of blight resistant trees. It’s part of a multi state effort to restore the species and a time consuming process in more ways than one.
“Oh this is a nice big nut. It will be viable for sure.”
About a dozen people are sitting at a long rectangular farm table carefully extracting chestnuts from their bristly green cradles.
“And then we go to a very advanced technology to test these nuts for their viability.”
Ned Yost is hosting this gathering -- that might other wise actually be quite a tedious process, in his barn at McDonald’s Mill in the Roanoke Valley.
“We have a little bit of water. We drop the nuts in. The good chestnuts sink and those that will not produce a tree next spring, they float.
Carl Absher, who runs the Virginia Chapter of the American Chestnut Foundation, collected these nuts a few weeks ago from trees he pollinated last summer. Match maker to the tree, he’s been at it for years harvesting the nuts from all but dead American natives that you can still find around here.
“ We really like to have a hundred from an individual tree expecting maybe 60 to survive and 3 or 4 to exhibit resistance.”
Resistance to the blight that decimated the American Chestnut comes from carefully cross breeding them with their Chinese Cousin which is immune to it.
“These are fifteen sixteenths American, one sixteenth Chinese. All the Chinese characteristics have been filtered out so as far as we’re concerned, if we see this tree growing it’s an American Chestnut you and I can’t distinguish that it’s a 16th Chinese.”
Breeding trees this way takes dedication and patience. It’s been going on in some form up and down the eastern part of the country for 90 years already. And as careful as these volunteers are, you can never be sure which trees will inherit resistance to the fungus. So scientists at Virginia Tech recently began genetic sequencing on the hybrids. Jason Holliday is Associate Professor of forest genetics and biotechnology.
“So if we can develop a ‘genoically’ – if that’s a word - informed model that will tell us about blight resistance without having to actually grow the trees that will be very helpful and definitely more cost effective.”
Holliday says he expects to have a good model to predict blight resistance as early as next year with a few more years of testing after that. And that has Science Director of the American Chestnut Foundation in Asheville North Carolina Jared Westbrook in Asheville North Carolina, contemplating something that for so long, has seemed so far off.
“How do we plant these out in the forest so that they will survive? They have been gone from the ecosystem for the last hundred years. What kind of sites, what kind of way do we need to work with the forest ecosystem.
He says, in their hey day, every fourth tree in this region was an American Chestnut.
“It was a keystone species in the Appalachian Mountains and now there’s still the nostalgia over the use of the wood, it’s very light weight, rot resistant timber. Now what motivates me to work on the chestnut is, it’s symbolic. We can actually use breeding and biotechnology to take a tree that’s functionally extinct and bring it back to life. And if we can do this with Chestnut is should be possible to do with other species like the Hemlock, like the Elm, like the Ash.
Westbrook, Holliday and others will discuss their latest findings at the Blacksburg Library this Friday afternoon 1-3 pm in the Blacksburg Library Community Room. 200 Miller Street.
"Restoration of American chestnut: A marriage of breeding and biotechnology," Jared Westbrook, quantitative geneticist and science director, American Chestnut Foundation
"Early screening of chestnut hybrid seedlings for resistance to chestnut blight and Phytophthora root rot," Anna Conrad, University of Kentucky
"Genomic selection for disease resistance in American chestnut backcross hybrids," Jason Holliday, Virginia Tech professor of forest genetics and biotechnology.