Minnesota Invasive Species Links

MAIRSC Website Minnesota Aquatic Invasive Species Research Center


DNR Aquatic Species  MN DNR Aquatic Invasive Species 


There seems to be some confusion about the caterpillar species we are seeing, so here are some interesting caterpillar facts.


There are 2 main species of tent caterpillar in our area.  Eastern tent and forest tent caterpillar.  The eastern tent caterpillars are the ones who get together and make a large white silken nest in your tree.  They often pick fruit trees or other ornamental type trees.  They also seem to prefer smaller isolated trees and bushes in ditches and along fence rows.


The forest tent caterpillar does not make this nest. Forest tent moths tend to lay their eggs in bigger trees, most commonly basswood and ornamental trees, but will also chew up oaks and hardwoods.  


The chemical we use will kill both species, BUT unfortunately, we cannot effectively control both species with a single application.  Eastern tent caterpillars hatch out a week or two earlier than the forest tent.  So if we spray when the eastern caterpillars hatch, we will be too early for the forest tent caterpillar.  By the time we spray for forest tent, the eastern tent are nearly finished feeding.


The attached picture shows the two species side by side.  The forest tent is on top of the picture and has hour glass shaped spots where as the eastern tent has a solid white or yellowish line along the top of its back.


If you have the white nests and they are low enough to reach, you can spray them with a contact insecticide from your local supply store, or if you really want to get revenge, dump some boiling water on them!


 To find out more about the spray used go to the website:  westcentralagair.com/forest-tent-caterpillar/

Minnesota Lakes & River Advocates

Find out how Minnesota Lakes & Rivers Advocates (MLR) is working to protect Minnesota water heritage and how you can get involved and stay informed. http://www.mnlakesandrivers.org/