WASHINGTON – The holly and the ivy may be little more than the ivy in parts of Maryland this Christmas.
Bright-green caterpillars called holly loopers ate the leaves of many wild holly trees around the state, stripping some of their leaves and leaving others virtually untouched, state agriculture officials said.
The critters munched in late summer, but the damage was not evident until October, after leaves started falling off the taller canopy trees like oaks, maples and hickories. That’s when the calls started coming in from holly-watchers in southern Prince George’s, Anne Arundel, Caroline and Baltimore counties, said Bob Tichenor, chief of forest pest management for the Maryland Department of Agriculture.
Hard-hit areas include the Accokeek and Piscataway areas of Prince George’s and Charles counties, he said.
In Charles County, holly loopers ate so many leaves off the trees around Dave Lines’ house that he can now see 400 to 500 yards into the woods, where visibility used to be limited to about 100 yards.
“They were all over the trees,” he said of the holly loopers.
Many of the trees “are stripped all the way from top to bottom” said Lines, a flower farmer who also manages a 173-acre tree farm. But other parts of his tree farm were untouched.
Not much is known about the holly looper, Tichenor said. The pest is usually found in the Gulf States and coastal Southeastern states, but it can migrate north.
The first holly looper outbreak was recorded in the South in 1972. Tichenor is hard-pressed to recall it ever causing damage in Maryland.
“As far as I know, there’s no record of an outbreak in Maryland, ever,” he said.
There are about 9,000 acres of trees and shrubs in the state, said University of Maryland regional extension specialist Stanton Gill. Neither Gill nor the state statistician’s office knows how many of those acres are holly.
But Gill said the native tree has a history in the state.
In the 1920s, people harvested holly from a large stand on the Eastern Shore for the Christmas market in Baltimore. During World War II, competition and variety from other states led people to stop harvesting from the wild.
Over the past 12 to 15 years, native holly has gotten more attention as a landscaping plant, and Maryland nurseries are growing more varieties of the tree.
“It’s a very, very popular and desirable landscape plant,” Tichenor said.
He said he did not hear from nurseries about the looper, and that careful tree-growers would likely have caught and killed the critters before they presented a problem.
Tichenor said his office fielded about 10 looper calls. “For an oddball thing like this, it’s a lot of calls,” he said. Most calls came from people who saw brown-leafed or bare hollies in the woods, but at least one was from someone worried about a holly in the landscape.
Experts said affected trees in the wild should recover, and landowners should not cut down or spray the trees.
But it may take a few years for the hollies to look normal again.
Hollies grow under canopy trees that shed their leaves every fall. But the holly trees constantly grow their leaves and tend to have three or more years of leaves on their branches at the same time.
Tichenor said the only thing for tree-lovers and homeowners to do is to be patient.
“Just because the holly had its leaves eaten doesn’t mean it’s dead,” he said.