Some American bison are contaminated with cow genes. The genes are left over from the early days of cross-breeding. (Photo by Paul Frederickson, Courtesy of Wikimedia Commons)
In iconic images of the Great Plains, you always see the land dotted with bison. Those bison helped make the prairies what they were. But the bison that you see on prairie preserves today are not exactly the same as the ones that once roamed the plains. The Environment Report’s Charity Nebbe has more:
We have a handful of ranchers to thank for the fact that we have any bison today. At one point there were only about a thousand and now there are half a million. Bob Hamilton is the Director of the Tallgrass Prairie Preserve in Oklahoma. He says the ranchers who saved the bison also put them at risk.
“Part of their motivation was also to see if they could cross breed bison with domestic livestock to see if they could produce a hardier winter resistant ‘beefalo’.”
The beefalo were not hardy and the ranchers abandoned their project, but the cattle genes remain. Bob Hamilton’s herd consists of 2,700 bison. Thanks to genetic testing, Hamilton has been able to weed out all of the bison carrying the most damaging kind of cattle DNA. But, there is some genetic material he just can’t get rid of. Chances are, there will always be a little bit of beef in the buffalo.
American chestnuts (left) are smaller than Chinese and European chestnuts. The Chinese and European varieties are also resistant to the blight, making the imports more desirable to growers. (Photo by Lester Graham)
American chestnuts were an important food source for wildlife because there was a more consistent crop each year than acorns. (Photo by Lester Graham)
Bill Nash of Nash Nurseries holds the spiny husks that hold the chestnuts. The American chestnut grove behind him is 20 years old and has not yet been hit by blight. (Photo by Lester Graham)
Food is always a big part of the holidays. But one
traditional food has – for the most part – disappeared from American tables. The Great Lakes Radio Consortium’s Lester Graham reports:
Food is always a big part of the holidays. But one traditional food has – for the most part – disapeared from American tables. The Great Lakes Radio Consortium’s Lester Graham reports:
(Sound of Nat King Cole singing, “Chestnuts roasing on an open fire…”)
That old chestnut of a song romanticizes roasting chestnuts as a part of the holidays. But a lot of us have never even seen chestnuts, let alone roasted them on an open fire. Chestnuts used to be a major part of the Eastern hardwood forest. There were millions of them. In fact, 25 percent of all the mature trees were chestnuts. But a blight, imported with some Chinese chestnut trees, slowly wiped out the American chestnuts. Now, they’re gone.
Well… almost. Much of the root stock is still alive. Sprouts grow until the blight knocks them back again. A blight only hurts the standing tree where it branches out.
And, in a few isolated pockets in the Midwest, the blight hasn’t reached the trees. A few American chestnuts are alive and growing and some of them are free of the blight. At Nash Nursuries in central Michigan, owner Bill Nash is guiding us through a rare sight… a grove of American chestnuts.
“These are 20 years old and as you can see, they’re fairly good sized. The American chestnut is quite a rapid growing tree. It’s well-suited for our climate, so it doesn’t have any of the problems that some of the hybrids do as far as growing and cultural care you have to take care of them. The Americans, you get them started and they’re pretty much on their own.”
In a few places in Michigan and Wisconsin there are small groves of chestnuts. They’re prized trees. They’re great for shade. The hardwood is rot resistant and makes great furniture and fence posts. And the chestnuts are eaten by humans and wildlife alike. Bill Nash says the tree will be popular again if it ever overcomes the blight that’s hit it so hard.
“The American chestnut will make another big comeback in this country as a yard tree, as a timber tree, as a wildlife tree.”
That part about a wildlife tree is more important than just worrying about the squirrels and bunnies. Chestnuts were an important food source for all kinds of animals.
Andrew Jarosz is a plant biologist at Michigan State University. He says the loss of chestnuts has been hard on wildlife populations.
“Chestnuts shed nuts in a more regular pattern than oaks, which will have what are called mast years – where they’ll have major crops, massive crops one year and very small crops in other years – which means it’s either feast or famine if you’re depending on oaks.”
Since the blight first began hitting American chestnuts about a century ago, researchers have been looking into all kinds of ways to stop it. One way is to cross it with the Chinese chestnut which has a couple of genes that resist the blight. But it takes a long time to breed out the Chinese characteristics from the American chestnuts and still keep the resistant genes.
Another approach is genetic manipulation. Genetically modifying the American chestnut tree to make it disease resistant. Again, work is underway, but it takes a long time. And even after success, it’s likely some people won’t like the idea of releasing a genetically modified organism into the wild.
The final approach worked in Europe when the blight hit there. It seems there’s a naturally occuring virus that kills the blight. It spread naturally in Europe. There are a few groves in Michigan that have naturally acquired the virus and it’s working to keep the blight at bay. Andrew Jarosz is working on the research. He says the trick is figuring out how to get the virus to spread to other trees short of manually spreading it on cankers infected by the blight.
“If we’re literally talking about millions of trees across probably, you know, the eastern third of the country, we obviously can’t treat every canker on every tree. And we need to be able to figure out a way to deploy the virus in a way that it can spread.”
Even with all that hopeful research, it’ll be ten years at least before some practical solutions end up in the forests, and Jarosz believes a couple of centuries before the American chestnut holds the place it once did in the forests.
Bill Nash knows it’ll be a while before there are major changes, but he is optimistic about the American chestnut.
“Oh, I would think the tree has a bright future. There’s enough people working on that, enough programs going on now… So, I would suspect that in the not-too-distant future we should have some of this progress made. You know, Robert Frost in his poem predicted the comeback of the American chestnut, that something would arise to offset that blight. And we’re starting to see that.”
Frost put it this way: “Will the blight end the chestnut? The farmers rather guess not, It keeps smoldering at the roots And sending up new shoots Till another parasite Shall come to end the blight.”
Seems Frost was an optimist too.
For the Great Lakes Radio Consortium, this is Lester Graham.