Aerial treatments conducted by Indiana DNR divisions of Forestry and Entomology & Plant Pathology to slow the spread of gypsy moth in selected areas of Allen, Miami and Wells counties are scheduled for tomorrow, if the weather allows.

Gypsy moth is one of North America's most devastating invasive forest pests and has caused thousands of acres of defoliation across the eastern United States.

Treatment begins shortly after sunrise but could be delayed until later in the morning or to the next day due to unfavorable weather conditions such as morning fog or rain. Treatment should take about an hour. A second treatment will occur four to 10 days after the first, weather permitting.

During treatment, a yellow airplane flying 75-125 feet above the treetops will conduct the treatment, starting at sunrise and continuing throughout the day, as the weather and flight schedules permit. With favorable weather, treatments may be completed by late morning or early afternoon.

The airplane distributes a spray containing the bacteria Bacillus thuringiensis var. kurstaki, referred to as Btk, into the treetops of infested areas where gypsy moth caterpillars feed on tree leaves. Btk kills gypsy moth caterpillars by disrupting their digestive systems after they ingest it.

Btk has been used for decades by organic gardeners and does not adversely affect people or animals. People who live or work near the treatment areas might want to stay inside when the planes are flying and for about 30 minutes after treatments are complete. This gives the material time to settle out of the air and stick to treetops. For more information on Btk, call toll-free at 1-866-NO-EXOTIC (663-9684) or call your county extension office.

Once treatment begins, rain or high wind may interrupt it for that day. If that happens, treatment would resume the next suitable day and continue until all sites have been treated.

All sites will receive two treatments. The timing of second treatments is also weather dependent, although those treatments will likely begin during the week of May 17.

To determine if your property is in the treatment areas or to view maps of all treatment locations, or for more information about gypsy moth, see gypsymoth.IN.gov.