Things have greened up nicely in the Northland, but winter deer damage to landscape cedars remains an eyesore.
"It's the worst I've seen it," said Craig Berryhill, certified arborist with Rick's Tree and Stump Removal in Duluth as he gazed at several shrubs devoured by deer over the winter.
Last winter's early heavy snow, burying deer's typical food sources, caused the area's considerable deer population to munch on cedar, or arborvitae, foliage instead. Their "browse line" leaves the lower portion of a cedar tree or bush stripped of its greenery.
"It's a very, very widespread problem," Berryhill said. "If your cedar hasn't been eaten by deer yet and you live in Duluth, you're probably on their list for next year."
Some homeowners are cutting back the damaged areas of their arborvitae to the trunk, giving them the look of deciduous trees.
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But is it a good idea?
A lot depends on what percentage of the tree or shrub has been ruined by deer, tree experts say.
If there is leafy tissue remaining, wait until the end of summer to see what happens, recommends University of Minnesota urban forestry professor Gary Johnson.
He said arborvitae will regrow new foliage even on lower branches that have been chewed. So as long as you can stand the unsightly appearance and lack of symmetry, wait it out, he says.
"You will see new growth start this summer," he said.
They can recover, as long as they're protected from deer during the next several winters by wire fencing, burlap or netting, Berryhill said.
"You only have to worry about it in winter," said Berryhill, noting deer have plenty of other plants to eat during the growing season. "Right now they're eating your tulips instead."
But if the greenery has been eaten down to the woody main stems, that part of the tree won't come back, said Bob Olen, horticulturist for the Minnesota Extension Service in St. Louis County. The only place the plant can fill in is on leafy tissue.
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If there's no leafy tissue left and you prune it back to the trunk, do so judiciously, Johnson recommends.
Don't remove too many branches, or the health of the tree will decline because it restricts the energy the plant has to recover. He likened it to having our legs removed, then being given less food to eat.
Do the least amount possible and do it in stages; trim back incrementally over several years, he said.
Berryhill said pruned-back cedars will survive if they are tall enough and the deer have not eaten most of them.
The tree should be at least twice as high as the browse line for such pruning, Berryhill said. "Otherwise, it will look like a Popsicle," he said.
Johnson's rule of thumb differed. He said 75 percent of the crown should remain. So a 16-foot tree could have the lower 4 feet of branches removed. He cautioned that pruning halfway up the trunk is removing more than 50 percent of the foliage because conifers have more foliage on the bottom half.
CANDACE RENALLS is at (218) 723-5329 or e-mail crenalls@duluthnews.com .
