Minnesota's Emerald Ash Borer Problem

June 3, 2022
By now, many have heard about the little green bugs crawling into the news, firewood and millions of ash trees across the country. The Emerald Ash Borer (EAB) is this invasive species that will soon infect and kill most of the ash trees in Minnesota. Minnesota is especially susceptible to this infestation because ash makes up a staggering 15 percent of the total tree population in the state. In the next few decades it is expected that almost all of these trees will need to be removed and replaced, making it one of Minnesota’s greatest challenges today.
ash tree in minnesota infected with emerald ash borer

About the Emerald Ash Borer

The invasive Emerald Ash Borer was first discovered in the United States in 2002 and moved to Minnesota by 2009. EAB is native to Eastern Russia, Japan, Korea and northern China.

The life of the EAB takes place below the bark of the ash trees. The EAB larvae will feed under the bark, and quickly infest the entire tree. This process of invading ash trees results in the trees becoming light-colored, referred to as “flecking.” Additionally, the presence of EAB in ash trees creates tunnels beneath the bark called “galleries.” The infestation of Emerald Ash Borer is dangerous for the health of ash trees because the EAB will disrupt the flow of a tree’s nutrients. Generally, once the symptoms are present, the tree will die within the next one to three years.

Considering the fact that there are roughly one billion ash trees in the state, the spread of the EAB has made a large impact on the communities within Minnesota. It would seem that the frigid winters that Minnesota experiences would help control the spread of the EAB, but unfortunately it does not stop the spread completely.

How to identify ash trees

Quarantine for infected trees

In order to slow the spread of EAB, the state enacted a quarantine on various types of product and waste wood. The quarantine now impacts 34 counties across the state, including Hennepin county and most of southeast Minnesota. It regulates ash logs, tree waste, and mulch, as well as all types of deciduous (trees whose leaves fall each year) firewood. This wood is free to move about within the quarantine zone but cannot cross its bounds. This quarantine system protects less infected areas by slowing the human caused spread of EAB. The bugs can only fly about a half mile radius from their original tree, but they can easily hitch a ride on pieces of wood, meaning many people unknowingly bring them to new areas. Much of the reason EAB has spread so fast is because of this human transportation. The quarantine may be a pain if you’re trying to transport ash wood, but it’s a must to keep EAB from infecting trees faster than they can be removed.

Emerald ash borer injections

Current solutions


If an ash tree has lost more than 50% of its foliage, treatment will likely fail. Otherwise, treatment is a viable option that can keep the tree alive for around 2-5 years, depending on the tree’s age and the severity of its Emerald Ash Borer (EAB) infestation. When treating ash trees for EAB, the chemicals emamectin benzoate and azadirachtin are injected directly into the tree’s trunk, acting as an insecticide, killing off any existing EAB and preventing new eggs from hatching. Ultimately, keeping ash trees alive will provide ecosystems with all of their benefits such as erosion control, animal habitat, and converting carbon dioxide into breathable oxygen. The insecticides must be applied every two years or there is a high risk that the EAB will resurface, so continual treatment would be necessary to prevent further outbreaks. Cities are encouraging private landowners to treat their ash trees, which prevents them from getting EAB in the first place. The largest and most notable downside to treating an EAB infested ash tree is that treatment will only delay the inevitable, which, as mentioned earlier, will occur within 5 years. While ash trees provide countless ecological benefits, and keeping them alive would seem to be the most sustainable solution, runoff of chemicals used to treat EAB can be harmful to other plant and animal life. Most tree care companies offer ash tree treatment; however, DIY treatment is also an option, with many online tutorials. Whatever you decide, it is important to ensure that the company or treatment method you are working with is following legal regulations, and is environmentally safe.


Whether your ash tree has EAB, or is just showing signs of dying, removal is the most environmentally safe course of action. Removing an infested or dying ash tree will prevent the insect or disease from spreading to other trees in the area. Another benefit to removal is that many companies will buy infested ash trees so long as there is some healthy wood inside, meaning that you could receive a profit from this action. Removing any tree will rid the area of any benefits that the tree provides such as erosion control, animal habitat, and overall health of the landscape. Many landscaping and tree care companies offer ash tree removal services. Removal can also be done yourself, so long as it is done safely and in a way that follows laws surrounding tree removal. Cities are also starting removal and treatment plans for ash trees on public land. Urban cities that are outside the quarantine zone make sure they only use ash wood that isn’t from the quarantine zone, and they have plans to remove and treat ash trees from their cities at a slow rate to be prepared for EAB reaching the city. Rural areas are trying to do the same thing on public land, but the main solution for private landowners is to log the wood and use it as firewood.

Leave it

Sometimes, ash trees can be too large, costly, or time consuming to treat or remove. In this case, it is best to simply allow the tree to live out its life cycle, and succumb to the infestation. The fully dead tree can then be recycled, mulched, composted, and more. This saves the money and hassle sometimes involved with treating and removing trees. Allowing EAB to fully consume the tree will increase the insect’s presence and chance that it will spread to other nearby ash trees.

Uses for waste wood


Biomass plants are a great solution for the infected wood. Biomass allows the wood to be burned for energy use in Minnesota. Using biomass is a carbon neutral way to create energy which means less emissions from fossil fuels would be released into the air. Biomass is also a more cost effective way to create energy than using fossil fuels because biomass is mostly dead crops, wood or solid waste. There are four biomass plants in Minnesota. However, some of these plants are not located in the quarantine area for EAB. These plants also can only take a limited quantity of wood which hinders the efficiency of disposing of the wood.


Putting the wood into a composting plant is also a sustainable way to dispose of the wood. Composting is used to recycle organic material like wood. Compost enriches soil and reduces the need for chemical fertilizers. The product of this composting process is either compost or mulch which is then sold to consumers like businesses or schools which need large amounts of it. In the Twin Cities, a good option is the Shakopee Mdewakaton Sioux Community Organics Recycling Facility, which processes waste wood.


Another way to repurpose the wood would be to use it in furniture, parks, and boardwalks. Hardwood is good for furniture, flooring, or even baseball bats. The wood could also be repurposed into wood chips to use in parks. It is important to get in contact with businesses that specialize in this craft in order for the wood to be used in these ways. Wood from the Hood is an example of a business that takes discarded wood and repurposes them into a variety of hardwoods. This company can only take specific tree parts, and transportation is needed to get the wood to their facility.

The VANTAGE Program

This article was written by Charlie Ballbach, Sarah Johnsen, Luke Miller, Mia Banks and Lauren Weick, students in the VANTAGE program. These students partnered with Clean Energy Economy MN (CEEM) to tackle Minnesota’s problem with Emerald Ash Borer and how it can be used to further biomass in the state. VANTAGE is a high school experiential learning program for high-achieving students. VANTAGE students partner with organizations in the community to complete projects each semester as part of their VANTAGE experience.

The projects must address a real issue, and they require an outside partner for the student team to work with. Ideally, the project would address a business need that an organization doesn’t currently have the bandwidth to address with itscurrent resources, so it would provide a win-win for students and the organization.

Students are enrolled in specific tracks, so projects are allocated in those areas. Opportunities include Global Sustainability, Business Analytics, Global Business, Design + Marketing, and Public Policy.

There is no cost associated with partnering with a VANTAGE team, but partners do have to invest a small amount of time (under six hours spread across 3 months). Clean Energy Economy MN members who are interested in participating can contact Virginia Mooty Rutter for more information.

Learn more about the VANTAGE Program

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