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South Dakota State University professor John Ball looks for Mountain Pine Beetles under some bark at Mt. Rushmore last summer. Ball has also set some traps that are intended to prevent the beetle from entering the tree. Photo by Josh Birnbaum/National Association of State Foresters |
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SDSU arborist wearing three hats
BROOKINGS Can't see the trees for the forest or the forest for the trees?
That old proverb doesn't apply to John Ball. He's at home one-on-one with a single tree and its owner or with a forest full of trees, in the Black Hills or in China.
In the course of his job he admits to wearing three hats.
Ball is a professor of forestry at South Dakota State University, a forestry specialist for South Dakota Cooperative Extension Service, and a forest health specialist for the state Department of Agriculture.
"Obviously a lot of my position involves the day-to-day work of just helping people figure out why their tree is dying, whether it's a tree in their yard or a shelter belt or in the woods," Ball said earlier this week when the Register visited him in his office in Agricultural Hall on the SDSU campus.
He apologized for the disarray, noting that he's in the process of settling in after moving from another office. But Ball doesn't spend a lot of time indoors, preferring to be in the field either here or abroad. For now his interests include "two particular pests," one already here in South Dakota, the other yet to arrive.
The pine beetle is doing its dirty work in the Black Hills, and Ball spends a great deal of his time there.
The other particular pest is the emerald ash borer (EAB) that will be coming to South Dakota; when it does it could well wipe out ash trees in the fashion that Dutch elm disease has devastated elm trees in South Dakota.
"There's no keeping it (the EAB) out," Ball said. "We lost that opportunity back in 2002, when it was first detected.
"There may have been a possibility of eradicating it from southwestern Michigan. But the dollars and interest were not there. Within a couple years it was too big to effectively eradicate."
No pine beetles East River
Some people might interpret Ball's realistic look at the critters that plague trees here in South Dakota as doom-and-gloom scenarios. But he does see some good news amidst the bad: take the mountain pine beetle, for instance.
While it's the native bug that is killing thousands of trees in the Black Hills right now, "it's not East River, nor will it come to East River or be an issue in East River."
There are ponderosa pines, the beetles' most common host, in this area; but even if some came, they likely would not thrive. Wood has been traveling back and forth from the Black Hills for more than a century.
He explained, "Even if somebody carried some pine beetles here, they certainly would attack a tree if they could; but they're not going to have the population build."
While that may be good news to East River residents, it can't be very comforting to some West River residents.
Once a Black Hills ponderosa pine is attacked by the beetle, there's no remedy: "Once a tree is attacked, it's dead; it just doesn't know it yet."
Add to that the trees "becoming very good beetle factories. Once a tree is attacked, generally speaking, the next year you'll find four to eight trees around it attacked."
The solution is simple but painful and costly to the landowner of the property where infected trees must come down. More than 30,000 beetle-infested trees have been found on 7,500 acres in the Black Hills.
Via a $170,000 grant, the federal government has made some money available to private landowners to cover the cost of tree removal.
Ash will go the way of elms
Turning to ash trees and the EAB, Ball expressed some skepticism at attempts to isolate and quarantine the pest. He cited the "famous barrier" between Detroit and Windsor in Ontario, Canada. It didn't work.
The EAB infestation spread eastward across the Canadian peninsula.
Ball said, "They (Canadians) actually cut a strip about 10 miles wide entirely across that peninsula of all the ash trees to prevent the spread further. Because the beetle would not be able to fly that far.
"Of course, the movement of the beetle is not by flight, but by truck carrying firewood. Somebody apparently carried firewood across that barrier, and now it's on both sides. Physical efforts to try to stop it will not work."
Ball sees the key to control as education and legislation that would prevent the movement of firewood or encourage people not to move firewood.
Michigan, with some exceptions in the Upper Peninsula, is pretty well infested.
Ash trees were at one time considered the ideal one-tree replacement for the elm trees devastated by Dutch elm disease. But by way of analogy, was it placing too many eggs in one basket?
"Oh, absolutely. A quarter of all our trees in South Dakota are ash trees," Ball said. "It was the ideal tree. It didn't matter about the soils. You could plant it anywhere. It grew fast.
"And, by the way, we're continuing to make that error. Nowadays people are not planting ash, of course, because of our fear of the inevitably (of the EAB). Now they're planting Freeman maples.
Such maples are fast-growing and provide incredibly good fall colors but ...."
Looking over his work-covered desk, Ball noted that "sooner or later, something's going to arrive from China or somewhere else, maybe 30 or 40 years from now that will attack that tree. And there will be a different professor sitting here, and a different reporter sitting there, saying "You know what? Why didn't we learn the last time."
Ball chalked up this too-many-eggs-in-one-basket approach to human nature: "We like to repeat patterns. What our neighbors plant, we'll plant. My best advice is, 'Look what your neighbors have planted and plant spomething else.'"
Lessons learned in China
Looking at different tree species that we may want to consider introducing to the U.S. and taking a look at "our trees from the U.S. that have been planted in China and seeing how they're faring."
The best example of that relates to the emerald ash borer. Ball has been traveling to China for the past 15 years, "before EAB was even discovered in the States and was virtually unknown in China."
Ball added that in northeastern China, where the EAB is native, "it does what the emerald ash borer should do: that is, attack dying ash trees."
He explained,"It performs a very important role. It takes trees that are going to die and kills them quicker and so recycles those elements."
But while healthy ash trees native to China are not being killed by the emerald ash borer, ash trees from America exported to and replanted in China are.
He said, "That might give us some ideas about something else we might worry about coming over."
'Llamas, goats, few trees'
Elm trees, ash trees, ponderosa pines all are prone to destructive pests. Is there any tree that is immune to attack, one species that would be good for South Dakota in general and Brookings in particular?
"Yes," replies Ball, with enthusiasm. "Yes. Ones we have in Brookings. If everyone in South Dakota planted gingko (biloba) trees, I'd be out of a job except we still have trees that are dying.
"And gingko has very, very few pests. If you take a look at the gingkos that we have in Brookings, you won't ever find one with a chewed-on leaf or a leaf that has a disease to it.
"Gingkos have been around for about 150-million years."
What about the flowering crab apple trees, in abundance in Brookings and lining many a street or boulevard? Nice tree to have around and immune to pest problems?
Ball responds with a hearty, "No. They've got more problems than you can shake a stick at. It would be better if they just died; but they don't die. They just hang on and look ugly.
"I get calls every August. Why are the leaves coming off the crab apples? Well, they're infected with apple scab. The disease won't kill the trees, but leaves will start falling in August.
"If we have a normal year, with a little moisture, the disease can really get going. You can drive through some streets in Brookings and find crab apple trees without a leaf on them by Labor Day. The trees won't die; they'll come back the next year, but by that August they'll look bad again. I'm not saying not to plant crab apples; we ought to dial it back and plant some other trees."
And what about trees on his own property in rural Brookings?
"If you drove by my place, you'd be incredibly disappointed," Ball said. Laughing, he added," We have llamas and dairy goats. Our trees are few. It's not a very well-treed lot."
Contact John Kubal at jkubal@brookingsregister.com.