LA CROSSE, Wis. -

An aerial attack to stop the spread of an invasive moth is ongoing this week.

Weather permitting, the Wisconsin Department of Agriculture has planes spraying a non-toxic pesticide to stop the spread of the Gypsy Moth once again this year.

This week, planes will be seen in La Crosse, Trempealeau, and Jackson Counties.

The goal is to slow the spread of the moth by focusing on areas where the pest has not been established. "It's all a matter of timing. The gypsy moth caterpillars have just hatched. They're moving up into the leaves to start eating. We want to get that spray on there so they will eat those leaves," said Rick Hummell from the Gypsy Moth Program.

Spraying has already been completed in Vernon County.