Gypsy Moth Program

Gypsy Moth Outlook 2012 and 2013

Egg Masses 2012-2013
Legend

Since the collapse of the gypsy moth populations in Pennsylvania in 2009, the state DCNR has been monitoring GM egg masses (which are a strong indicator of the following year's population size and vigor) on an annual basis at 2,230 sites throughout the state. Based on the number and rapid increase in egg masses from 2010 to 2011, DCNR expects this year to exhibit a major expansion of the state-wide gypsy moth population leading to a major problem year in 2013. This expansion will most likely be affecting Centre County. Moreover, the average size of the egg masses is very large, indicating healthy emerging populations that are not affected by viral and fungal diseases.

Prediction for Centre County in Summer 2012
DCNR predicts that there could be some noticeable defoliation in the State College Borough and Ferguson, Harris, Potter and probably other southeasterly townships most likely from a southerly blow-in of caterpillars from the Tussey ridgeline and Huntingdon County. These defoliations are unlikely to be major ones, but if they occur, the result will be the establishment of substantially larger populations which will emerge from egg masses in the spring of 2013.

Prediction for Centre County in Summer 2013

Although forecasting insect populations gets more difficult with time, DCNR predicts from the present vantage point (April 2012) that 2013 could be a major gypsy moth year in our county and throughout the state, leading to defoliation in many areas. For the first time in twenty years, counties to the west of Centre, almost up to the Ohio border are showing gypsy moth activity.

Are there any Gypsy Moth Spray Programs Planned for 2012?

No. Federal and State funding for gypsy moth suppression projects has historically only been made available after a risk has been proven (high numbers of egg masses in an area). It is near impossible to plan advance spray programs based on the likelihood of blow-in populations as there is no simple method to accurately survey affected areas (tiny mobile caterpillars are much harder to count than static egg masses on a tree).

In some of the more affluent townships that have large suburban populations living in forested communities, it may be possible to respond to large blown-in caterpillar populations by organizing a spray program at short notice. However the biological insecticide that is universally used for spraying populated areas because of its safety, Bt, is less effective with the later-stage caterpillars.

How about Spray Programs for 2013?

The entomological events of 2012 will determine whether any spray programs will be required. With state and federal budget cuts, it is hard to predict whether gypsy moth suppression programs will be funded. However, legislators have usually responded to homeowner calls by releasing some funds for cost-share programs in bad gypsy moth infestation years.

Homeowner Measures

Most of the homeowner gypsy moth control measures work when young caterpillars are dispersing on tree trunks. Once a population is established in a canopy the only local measure that can be used is trapping and removal with burlap bands that is described elsewhere on this site, but this has only a limited effect. Eradicoat, which proved popular during the last outbreak, is alas no longer available.

This site will be updated as more information on the gypsy moth situation becomes available.

The associated map provided by DCNR shows the sites sampled in Centre and surrounding counties in the fall and spring. Note that there were still many sites that showed no GM egg masses (clear circles).

Karl Mierzejewski
Gypsy Moth Coordinator

Maps

2009 Program

In 2009, a map of the county depicting reported gypsy moth activity was prepared and is available HERE. The map will open in a new page. To enlarge sections of the map, use the magnifying glass tool to draw a box around the geographic area of interest.

On May 22, 2009, the Department of Conservation and Natural Resources Gypsy Moth Spraying Program was completed in residential areas of the county. As in previous years, the program focused on forested residential lands, providing spray coverage (upon request and acceptance) within a 500-foot radius of year-round and seasonal dwellings.

2010 Program

The collapse of the gypsy moth in Centre County as well as other areas of the state indicates that there will NOT be a Gypsy Moth Suppression Program in 2010. In order to keep the public involved and aware of a future infestation, volunteers will be identifying and tracking gypsy moth egg masses in order to limit the severity of future outbreaks of population. Whether Centre County will participate in a future program will depend on several factors, including the distribution of new egg masses in the county and available funds.