Gypsy moth caterpillar populations are extremely high throughout the oak forests in northern Michigan. The presence of caterpillars has been a nuisance, and many oak trees have been severely defoliated as the caterpillars continue to eat the leaves.
What can you do?
Installing sticky bands on trees can help keep the gypsy moth caterpillars from climbing back up the trunk of a tree. On hot afternoons, gypsy moth caterpillars spin a web to lower themselves down from the tops of the trees to escape the heat. In the evening, or the next morning, the caterpillar will attempt to climb back up the trunk of the tree to begin feeding again.
Sticky bands prevent the caterpillar’s ascent. Dozens if not hundreds of caterpillars will congregate below the sticky tape where they can easily be targeted with a soap and water spray or plucked off and collected in a bucket of soap and water. Repeat daily.
Sticky bands can be constructed using duct tape and petroleum jelly. Simply wrap three overlapping bands of duct tape, sticky side down on the bark, around the tree. Then, take a small amount of petroleum jelly on your finger and run it across the middle band.
Applying petroleum jelly directly to the bark is not recommended and could injure the tree. Similarly, applying too much petroleum jelly will cause it to melt and run down the tape and come in contact with the bark, causing injury.
It may be tempting to use a chemical insecticide on the caterpillars. However, that is not recommended due to the many beneficial insects that could be affected. Rather, use a heavy mixture of soap and water to spray the caterpillars directly.
In addition, while young caterpillars are lethally affected by eating the bacterial insecticide, Bacillus thuringiensis kurstaki, or Btk, applied to the leaves…
Source: Big Rapids Pioneer