DCNR, Game Commission Spraying Woodlands to Combat Gypsy Moth Damage
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Bracing for a Spring that could be marked by increased gypsy moth infestations and heavy defoliation in some areas of the state, the Department of Conservation and Natural Resources and the Game Commission announced plans this week to expand their aerial spraying efforts to suppress the woodland insect pest.

Game Commission officials announced they have scheduled gypsy moth spraying for a total of 42,731 acres of its more than 1.4 million acre State Game Lands system. Spraying will cover 38 different SGLs, and will occur in late April to early May, as soon as leaves pop out and gypsy moth egg masses hatch.

After a virtual collapse of gypsy moth populations in recent years across most of Pennsylvania, insect numbers have increased to the point where spraying will be necessary on 221,831 acres in 27 counties, the state Department of Conservation and Natural Resources said.

"As we anticipate more gypsy moths, it's very important to remember spraying is designed to protect trees in forested landscapes from moderate to severe defoliation," DCNR Secretary Michael DiBerardinis said. "We can't eradicate an insect that's well established in Pennsylvania and is here to stay."

A total of 64,900 acres of private, state and federal woodlands were sprayed in 19 counties in spring 2007; gypsy moth caterpillars defoliated 681,000 acres.

This year, 21 counties enrolled 95,305 private acres in the program; up from the 11 counties that requested 35,900 acres be sprayed in 2007.

"In this voluntary program, counties and cooperating agencies share the costs of private land treatment," Secretary DiBerardinis said. "This acreage, as well as state lands to be sprayed, is concentrated in the northeast and north- and south-central regions of the state where there have been three consecutive years of oak defoliation by gypsy moth larvae.

"These state lands are selected based on the number and concentration of gypsy moth egg masses, previous defoliation, and ecological, historic, or economic significance."

Nine helicopters and five fixed-wing aircraft will begin the spray program in early May and end shortly after Memorial Day. Spraying is dependent on weather, foliage development and caterpillar development.

"Thanks largely to the gypsy moth's natural enemy — Entomophaga maimaiga — moth numbers had been way down for several years in most areas of the state, and spraying was not necessary," said State Forester Daniel Devlin. "Spraying helps contain the widespread gypsy moth damage we have seen in the past, but the major controlling factor is, and will continue to be, the prevalence of this fungus in our woodlands."

Counties enrolled in 2008 and private acres to be sprayed are: Adams, 370; Bedford, 1,196; Berks, 862; Blair, 582; Centre, 13,371; Chester, 200; Clearfield, 300; Cumberland, 14,443; Dauphin, 11,366; Franklin, 5,115; Fulton, 4,582; Lackawanna, 507; Lebanon, 7,991; Luzerne, 7,761; Mifflin, 435; Monroe, 1,666; Perry, 4,308; Pike, 11,236; Snyder, 1,178; Union, 1,186; and York, 6,650.

In addition, state parks and forestlands, state game lands and other woodlands will be sprayed in Carbon, Clinton, Huntingdon, Lancaster, Juniata and Somerset counties.

Gypsy moth populations dropped sharply between 2000 and 2006, when 700,000 acres of woodlands were defoliated as DCNR treated 82,000 acres in eight counties.

Following a 76-percent reduction in defoliation during spring 2002, DCNR opted not to conduct aerial spraying in 2003, 2004 and 2005, when gypsy moth populations sharply declined due to Entomophaga maimaiga.

"Those participating in spring gobbler seasons may encounter helicopters or other aircraft spraying State Game Lands or other forested areas," said William Capouillez, Game Commission Bureau of Wildlife Habitat Management director. "We want those hunters to rest assured that the spray being used is not harmful to humans, and only will impact gypsy moth caterpillars when they ingest the spray."

The Game Commission will pay $1,349,993.58 out of agency's Growing Greener II funding to the state Department of Conservation and Natural Resources, which oversees the Statewide Cooperative Spray Program for gypsy moths.

"In the summer of 2007, a statewide inventory of gypsy moth impacts on SGLs identified defoliation on more than 93,000 acres," Capouillez said. "To prioritize and focus spraying efforts, we looked at a series of factors, including: the importance of oaks on a particular SGL; socio-political impacts of each SGL; whether there were existing Important Bird Areas, Important Mammal Areas or critical/unique habitats on the SGL; past gypsy moth impacts and resulting forest habitat conditions; and financial values of timber stands."

From this point, the Game Commission identified the 42,731 acres in most critical need of treatment to prevent similar defoliation or loss due to the expected gypsy moth hatch this year. Based on the present data, all spraying will occur in the Northcentral (5,970 acres), Southcentral (27,818 acres), Northeast (1,116 acres) and Southeast (7,827 acres) regions. The Northwest and Southwest regions, which suffered little to no gypsy moth defoliation, are not slated for spraying at this time.

A list of those areas to be sprayed by the Game Commission is available online.

All areas will be treated this year with the biological insecticide, Bacillus thuringiensis (Bt), comprised of naturally occurring Bacillus spores. No chemical insecticides are used.

Gypsy moths are one of the most destructive forest pests in Pennsylvania. Feeding while in the larval — or caterpillar — stage, the insect hatches and begins feeding from mid- to late April in southern Pennsylvania, and in early- to mid-May in the northern part of the state. Oak, sugar maple, beech and aspen trees are affected the most by the forest pest.

When populations peak, the insects may strip trees of foliage, leaving them weakened and susceptible to disease, drought, and attack by other insects. A tree begins to suffer when 30 percent or more of its leaf surface is lost.

Forest insect spray programs are a cooperative effort among DCNR's Bureau of Forestry, county and municipal governments, and the U.S. Department of Agriculture Forest Service's Forest Health Protection Unit.

The gypsy moth was introduced to North America in 1869 at Medford, Mass., where it was used in a silk-production experiment. The gypsy moth first reached Pennsylvania in Luzerne County in 1932, and since then has infested every county.

Homeowners and other private property owners can learn more about the gypsy moth, the damage it causes, and small-scale efforts to combat it by visiting the Frequently Asked Questions webpage.

For information on the progress of gypsy moth spraying activities, visit the Spray Progress Report webpage.


4/25/2008

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