Fewer gypsy moths are expected in Maryland

ON THE FARM

October 05, 2008|By TED SHELSBY

Based on preliminary information from pest management officials with the state Department of Agriculture, the shade trees in your yard are less likely to fall victim to voracious caterpillars next year than in the recent past.

The state reports that a naturally occurring fungus caused by wet spring weather, along with the Agriculture Department's effective suppression program, has resulted in a decline in gypsy moth defoliation this fall as compared with last year.

State officials also expect less of an attack by the leaf-eating caterpillars next year.

"We will not know for certain until our egg mass surveys are completed in December, but we expect less of a gypsy moth problem next year," said Sue DuPont, a spokeswoman for the Department of Agriculture.

Last year, Maryland suffered its worst infestation of gypsy moths since 1995. The damage spanned 14 counties and Baltimore City, including all the counties in the Baltimore metropolitan area, and ranged from Cecil to Garrett County.

During an infestation, tens of thousands of gypsy moths in their caterpillar stage attack a tree, eating the leaves and robbing the tree of nutrients. Many trees die, while others in a weakened condition are done in by other insect predators, including the two-lined chestnut borer.

State officials say that as many as 15 percent of the trees in an infested area will die.

The damage inflicted by gypsy moths is more noticeable in thick forests, where it is easy to see acres of trees that have lost their leaves.

But the shade trees in homeowners' yards are more at risk. They are out in the open and not protected by surrounding trees, an Agriculture Department official explained.

The caterpillars are usually tiny, about an eighth of an inch long, when they begin feeding on trees. They eventually grow to about 2 1/2 inches long.

The gypsy moth attacks in force. At one Harford County home, the caterpillars were several inches deep beneath trees last year, according to a University of Maryland entomologist.

People usually first notice an infestation when their yards become sunnier, as the leaves from their shade trees disappear.

Last year, Maryland was on the edge of a gypsy moth infestation that spread from eastern West Virginia, through Pennsylvania and into New Jersey.

This year, the Department of Agriculture reported the defoliation of trees on 19,279 acres in 14 counties and Baltimore City.

Seeking to prevent a recurrence of last year's infestation, the Agriculture Department treated trees on more than 99,000 acres of land this spring. It was the department's most aggressive attack against the tree-killers since 1995. It estimates that aerial spraying was 97 percent effective in preventing defoliation. "We encourage property owners and residents to report the presence of any gypsy moth caterpillars, egg masses, or defoliation so that our assessment of any future infestations, as well as our planning for next year's suppression program, is as thorough as possible," said Agriculture Secretary Roger Richardson.

In late June or early July, each gypsy moth female lays about a thousand eggs in a single mass. Gypsy moth egg masses are about the size of a quarter, oval, raised in the center and tan to light brown in color.

Because the female moth deposits hairs and scales from her body in the mass, it appears slightly fuzzy. The mass adheres to the surface on which it is laid - it is not a web, tent or bag.

The egg mass will remain where the female laid it until spring, when the tiny caterpillars hatch.

Agriculture officials tell homeowners to look for egg masses in shaded, protected places such as the underside of tree limbs, crevices in tree bark, ivy-covered tree trunks and buildings. They can also be found on the underside of lawn furniture, inside the wheel wells of campers and trailers, under the eaves of houses and storage sheds, on the foundations of houses and in woodpiles.

Baltimore Sun Articles
|
|
|
Please note the green-lined linked article text has been applied commercially without any involvement from our newsroom editors, reporters or any other editorial staff.