It’s been about a century since Americans have
been able to celebrate the holidays by roasting native chestnuts over an open
fire. Almost every one of America’s more than 4 billion chestnut trees from
Maine to Georgia was wiped out by chestnut blight, a fungal disease that spread
like wildfire after its accidental introduction into the U.S. from trees
imported from Japan to the Bronx Zoo in 1904.
The tree’s disappearance has dramatically changed
the landscape of eastern North America. Chestnuts were once the dominant tree
in eastern forests, and its wood was used for fence posts, railroad ties,
utility poles and anything else that required rot-resistant lumber.
Many of
Rhode Island’s historic homes were once sheathed in it.
American chestnut tree, via The Rural Blog |
In addition, the edible nuts provided vital
nutrition to wildlife and were an important element in cattle and hog feed. And
because the nuts ripened right around Thanksgiving, they became a popular snack
during the holiday season (and a key lyric in that most popular of Christmas
carols).
All but the caroling ended soon after the blight
took hold. The few chestnuts we eat these days come from non-native species
imported from overseas.
But that may not be the case in the coming years, thanks
largely to efforts by the American Chestnut Foundation and a little help from
local volunteers. A number of research projects are underway designed to
develop blight-resistant trees so the species can be restored in our forests.
URI Master Gardener Rudi Hempe is one of the
volunteers. He and a team of about 25 other master gardeners who call
themselves Rudi’s Rangers are growing a one-acre breeding orchard and a
two-acre seeding orchard of chestnut trees on land owned by the South Kingstown
Land Trust.
The trees they planted originated with seeds from
a single tree in East Greenwich and another one in Exeter that apparently have
a genetic abnormality that makes them immune to the blight. Those two parent
trees are among the very few mature American chestnuts that did not succumb to
the disease, and they are giving scientists a starting point for studying
disease resistance.
When the trees planted and maintained by the
master gardeners grow tall enough, Rudi’s Rangers will inoculate them with a
low-dose of the blight in hopes that some will develop a resistance to the disease.
Similar efforts are underway at three other locations in Rhode Island and at
dozens more in Massachusetts, Maine and elsewhere in the tree’s original range.
In a separate study, the chestnut foundation is
also crossing American chestnuts with a similar species from China that is
naturally resistant to the disease. Five of those hybrid trees were planted at URI’s East Farm several years ago, and three of them are still going strong.
It is uncertain whether any of these studies – or
others approaching the problem using biotechnology tools – will bear fruit. It’s
likely to take a decade or more to find out. But we’ve waited far longer than
that already. The wild trees have been gone for so long that almost no one
alive today has any recollection of how stately a chestnut forest looked before
the blight.
But hopefully, in the not too distant future,
singing about roasting chestnuts will have a new, deeper meaning to carolers –
and all Americans – once the majestic trees make their heralded return.
This article first appeared in the Independent on December 21, 2017.
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