Fewer gypsy moths are expected in Marylanders' backyards next year

The Baltimore Sun

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.

"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 counties.

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 it is the shade trees in homeowners' yards that 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 more sunny, 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 97.2 percent effective in preventing forest 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 thorough as possible," said Agriculture Secretary Roger L. Richardson.

In late June or early July, the gypsy moth females lay 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 the following 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.

Residents also can get information or report egg masses, caterpillars or defoliation by calling the state Department of Agriculture at 410-841-5922.

When nature attacks

For grain farmers, wildlife in the form of deer, geese, bears and groundhogs can be even more destructive than the gypsy moth.

Maryland farmers lost an estimated $9 million in potential crop production last year because of wildlife damage, according to a survey by the state office of the U.S. Department of Agriculture's National Agricultural Statistics Service.

The results were collected and tabulated from the USDA's fall acreage and production survey, which featured nearly 1,400 reports.

Damage statewide was attributed to the following wildlife species with the corresponding estimated percent loss caused by each species: deer, 84 percent; groundhogs, 7 percent; resident geese, 3 percent; migrant geese, 3 percent; bears, 1 percent; and other species, 2 percent.

Estimated economic loss was the greatest in northern central Maryland, with crop losses reported at $2.6 million, 29 percent of the state's total estimated losses.

The lower Eastern Shore reported $2.2 million in damage; Southern Maryland, $2.1 million; the upper Eastern Shore, $1.8 million; and Western Maryland, $300,000.

Crop farmers spent an estimated $600,000 last year on preventive measures such as fences, frightening devices and repellants.

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