Picture of an emerald ash borer

Emerald Ash Borer (EAB) in Saint Paul

Emerald ash borer (EAB) is a destructive insect pest that attacks and kills all species of ash trees (Fraxinus genus) native to North America. EAB is native to Asia and has no natural enemies in North America. The adults are small, iridescent green beetles that live outside of trees during the summer months. The larvae are grub or worm-like and live underneath the bark of ash trees. Trees are killed by the tunneling of the larvae under the tree's bark.

The first infestation of EAB in Minnesota was discovered in Saint Paul in 2009, though it is believed that it arrived as early as 2004. While EAB spread starts slowly—usually undetected in the upper canopy of ash trees—it reproduces exponentially and advances quickly to kill all of a community’s ash trees, usually within 10-15 years of arrival. Now 20 years in (2004-2024), EAB in Saint Paul remains at a critical stage. 

Emerald Ash Borer (EAB) Resources & Information

Ash tree management map

Ash Trees Painted With Green Rings

Green paint is only used on ash trees, and signifies they have been marked and scheduled for removal. The other most commonly used paint color on trees is red, which also signifies removal, but is used for any non-ash species. If you have further questions regarding paint being used on trees, please call Forestry Customer Service at 651-266-6400.

Forestry will begin marking 2024 Structured Removal ash trees in December and will begin removing those trees in January. Please refer to the Structured Removal web page and the interactive EAB web map for more information about the removal plans for 2024.

Emerald Ash Borer (EAB) in Minnesota & Nationwide

Emerald ash borer was first discovered in SE Michigan in 2002, but it is thought to have been present since the early 1990's. Since its' arrival to North America, it has spread to numerous states and Canadian provinces. Check the links below for the most up-to-date statewide and nationwide EAB information.

Additional Emerald Ash Borer (EAB) Resources

Emerald Ash Borer Information Network

Minnesota Department of Agriculture logoMinnesota Department of Natural Resources logoUniversity of Minnesota Extension Service logo

Last Edited: March 7, 2024