Skip to main content
T
T
T

Exotic and Invasive Species

In 2023 the Minnesota Department of Agriculture (MDA) confirmed Emerald Ash Borer (EAB) in portions of Cass County, including a segment of Chippewa National Forest Lands.

Because EAB has been identified in Cass County, the MDA has placed a formal quarantine for a portion of the county, which limits the movement of firewood and ash material out of the area.

The northern border of the quarantine extends west from county line along highway 34 to Walker, Highway 200 to the southern exterior border of Leech Lake Band of Ojibwe, north to highway 200 and east to the county border. For quarantine area details, please see the Emerald Ash Borer Status Map.

No regulated articles are legally allowed to move outside of the EAB quarantine area. Regulated items include:

  • Ash logs
  • Ash tree waste
  • Ash chips and mulch
  • All firewood (non-coniferous)

The MDA issues quarantines for all areas known to have EAB to reduce the risk of further spreading the tree-killing insect.

More about EAB:

Emerald ash borer (EAB) larvae kill ash trees by tunneling under the bark and feeding on the part of the tree that moves nutrients up and down the trunk. Often, the trees show several signs of infestation because of this. Woodpeckers like to feed on EAB larvae, and woodpecker holes may indicate the presence of emerald ash borer. Also, EAB tunneling can cause the bark to split open, revealing characteristic S-shaped galleries underneath.

Emerald ash borer (EAB) is an exotic beetle that was discovered in southeastern Michigan near Detroit in the summer of 2002. The adult beetles nibble on ash foliage but cause little damage. The larvae (the immature stage) feed on the inner bark of ash trees, disrupting the tree's ability to transport water and nutrients. This is what kills the tree. The EAB on its own only moves short distances each year, however through the transport of firewood EAB is spread much more rapidly. 

Reporting EAB:

If you think you have emerald ash borer on your property, or think you may have spotted it somewhere else, here is what you should. 

If it looks like emerald ash borer or emerald ash borer damage, in Minnesota call (888) 545-6684 (Arrest-the-Pest Hotline) 

Biological Control of Emerald Ash Borer (Minnesota Department of Agriculture):

The goal of biological control is to use natural enemies to bring emerald ash borer (EAB) populations into balance and reduce damage.  

  • Biological control is the only management option that can be applied at the forest landscape level.
  • Three parasitoid wasp species are released in Minnesota. Two species attacks the larval stage of EAB under the ash bark. The other species kills EAB eggs that are in bark crevices. These wasps are small like gnats and do not harm humans. They were selected by the U.S. Department of Agriculture’s Animal and Plant Health Inspection Service (APHIS) and Forest Service and tested extensively to ensure that they will not negatively impact other species or the environment. APHIS rears these biological control agents at a specialized facility in Brighton, MI and provides them to states with EAB infestations. 

For More Information:

Last updated May 23rd, 2025

Return to top