A program is trying to save another
native tree that’s being wiped out by an invasive
fungus. People who like the butternut are hoping
that by planting more seedlings, and tracking
mature trees, they’ll find some are resistant
to a blight that’s killing the butternuts.
Lucy Martin reports:
Transcript
A program is trying to save another
native tree that’s being wiped out by an invasive
fungus. People who like the butternut are hoping
that by planting more seedlings, and tracking
mature trees, they’ll find some are resistant
to a blight that’s killing the butternuts.
Lucy Martin reports:
Butternuts are rich in history. Native Americans used the tree for
medicine and dye. They ate the nuts. During the Civil War, so many
Confederates used the tree’s yellow-brown dye to make home-spun
uniforms that their army picked up the nickname “butternuts.”
Wood ducks, finches and songbirds eat the tree’s spring buds. The fall
nut crop feeds woodpeckers, turkeys, squirrels and other wildlife.
The tree’s hard wood resembles walnut, but with a lighter, golden tone.
That’s why it’s sometimes called “white walnut.”
The trees are seriously threatened by butternut canker, an invasive,
airborne fungus. The blight was first noted in Wisconsin in 1967. In
some states, up to 90% of all butternuts are now affected, but there’s
work underway to try to save the butternut before it’s wiped out.
Tucked in an old orchard, a cold-storage room serves as a distribution
station. Each spring, this is where the Rideau Valley Conservation
Authority gives away seedling trees to the public. Project technician
Rose Fleguel gave me the tour:
“So, I think there’s about 100,000 seedlings here. These are boxed or
bagged so that the trees stay moist and dark. We’ve already spent two
days re-packing into individual landowner tree orders.”
At this time of year, the dormant seedlings just look like twiggy
sticks. Many are still wrapped in brown paper sacks. Conservation
agencies plant all kinds of trees. But sometimes they target very
specific problems, like butternut canker.
“My thing is the Butternut Recovery Project, whatever amount of land
can sustain 10 seedlings, then you’re free to take the seedlings and
plant them out. ‘Cause what we’d like to do is get the seedlings out on
the landscape, get them growing. Replace the ones that have been killed
by this disease, already, and that continue to be killed, and hope for,
I mean, it’s going to be, it’s going to be a shot in the dark, but hope
that maybe some of these seedlings might be resistant.”
“Hope” is the key word. It’s not clear whether any butternuts are
resistant to the canker blight. The seedlings being handed out are
from trees that are still healthy. This recovery program also maps
mature trees and keeps track of the ones that still seem to be canker-
free. It’s a long shot, called “find the resistance.”
Rudy Dyck is the Director of the local Watershed Stewardship Services.
He says you can usually see if a butternut has been attacked by the
disease:
“Look for black patches, black streaks, black sooty areas on
the main stem, at the root collar, and always look on the underside of
the large branches, because that seems to be where the canker first
infects.”
“And if you notice that, is there anything to be done?”
“No, there’s nothing you can do. We’re asking people to keep them, as
long as they can. But one of the reasons that butternut is in such
extreme danger of extinction is that it just does not regenerate very
well.”
Dyck says that’s why it’s important to conserve existing trees.
Butternuts don’t bear seed each and every year. And when they do, the
nuts tend to get gobbled up. Growing new butternuts takes a few tricks:
“You have to stratify them, or prepare them for growing, the next
spring. So they have to spend a few months in kind of freezing
temperatures, an un-insulated garage in a pot of peat moss, or
something. Another strategy some people do, is they bury the nuts in
the fall, and they cover them with chicken wire, and then that protects
them from squirrels during that fall period and, as they start to grow
next spring, you can transplant them.”
Dyck says US and Canadian agencies are sharing ideas and results
because diseases don’t stop at borders:
“There’s literally thousands and thousands of heavily cankered, dying
butternuts out there, and we really want to focus on looking at
healthy, canker-free trees. Because those are the trees we want to get
into our geo-data base, for future seed collection, those are the trees
that may hold some resistance and those are the trees we want to
track.”
Butternut canker isn’t a well-known problem. The beautiful trees are
too big for most yards. They’re usually sparsely scattered in forests,
or old farmsteads. But Dyck says the butternut has an important place
in nature.
“There’s no question, bio-diversity and having many, many types of
ecosystems, habitats, species. They all interact, they all count on
each other, and it all makes for a healthier environment and place for
us all to live.”
Many native trees such as the chestnut, elm, and now the ash, are under
attack from invasive diseases or pests. The butternut is yet another
tree biologists want to save for future generations.
For the Environment Report, I’m Lucy Martin.