Pasture management

By Tanner Marquardt

Student Intern

University of Minnesota

Extension

PRESTON, MN — As of June 1, 2023, the Minnesota Department of Agriculture warned to watch for the tree of heaven and the spotted lanternfly. These are two invasive species that, at the moment, are not common throughout the state, but they are spreading closer to the southeast corner of Minnesota from the eastern United States.

The tree of heaven is an invasive plant that produces abundant seeds, crowds out our native species, and secretes a chemical into the ground that is toxic to surrounding plants. It has smooth gray bark with chestnut brown twigs. It has large leaves that grow between one to four feet in length. Each one of these leaves contains 11-41 smaller leaflets. Around June it produces clusters of small yellowish-green flowers that may have an unpleasant odor. The tree can be found almost anywhere from the edges of river banks to openings in a forest. However, they are intolerant to shade so they cannot grow under the canopy of an established forest. The tree will begin to take over forests during times when the canopy thins and allows enough light to pass through for the tree of heaven to establish itself.

The spotted lanternfly is an invasive insect species, and its preferred host is the tree of heaven. However, it will feed on many economically important plants as well. Spotted lanternflies are roughly 1-1 1/2” long. They are gray with black polka dots on their upper wings, and their lower wings are a combination of black, red, and white. The larvae are black with white spots, and as they approach adulthood, they become red with spots. As they eat the sugary sap from plants, they expel excess sugar water called honeydew.

Besides the damage that can be done by the lanternfly eating the plants, the main concern is the black sooty mold that grows on the honeydew left behind after the lanternflies feast. This mold causes more damage to plants than the bugs themselves. While sooty mold can easily be washed off, it can make grapes and other fresh fruits unmarketable. Some ways to control the spread of lanternflies are to remove host plants, and finding and destroying eggs. For small amounts of lantern flies, you can build a circle trap which is essentially a net tied to a tree that funnels the lanternflies into some sort of container that they cannot escape from.

This information was sourced from Pennsylvania State University Extension, University of California, University of Minnesota Extension, MN Department of Agriculture, and Pennsylvania Department of Agriculture. If you find either the tree of heaven or the lanternfly please report it through the Minnesota Department of Agriculture “Arrest the Pest” program that can be found on their website. If you would like confirmation that what you found is the spotted lanternfly or tree of heaven please reach out to your local Extension educator. Residents of Fillmore or Houston counties can call (507) 765-3896 or (507) 725-5807.