Emerald Ash Borer (EAB) is an invasive insect that has killed millions of Ash trees throughout North America. Since 2009, EAB has been detected in 46 counties in Minnesota, including Anoka County. MN is home to over 1 billion Ash trees, all of which are vulnerable to EAB infection.

Trees affected by EAB dry out and rot quickly, creating public safety hazards. If allowed to decay, these conditions can cause trees to become dangerous to manage. Removing ash trees in high-traffic areas including along public trails and neighborhood streets is a top safety priority. Learn more about Emerald Ash Borer on the ACD Website.

Oak Wilt is a fungal disease that affects all species of oak trees. It is spread by sap beetles and through the tree's root systems. The disease affects Oak species differently; it can kill Red Oak trees in 2-3 months whereas White Oaks can live up to 20 years after becoming infested. It's important to know the signs of Oak Wilt to prevent further forest damage. Learn more about Oak Wilt on the ACD Website. 

 Help Stop the Spread!

Avoid cutting and pruning Ash trees from May 1 - September 31 as EAB insects are most active during this time. Do not transport firewood offsite from where it was collected. The Twin Cities metro and much of Eastern, MN is within an EAB quarantine zone and transporting firewood out of these areas risks spreading EAB.

Avoid cutting and pruning Oak trees from April 1 through July 31 as sap beetles are most active during this time. Treat spring and summer tree wounds with a water based paint or pruning wound sealer to avoid attracting sap beetles. Do not transport firewood off the site where it was collected. The Twin Cities metro and much of east central Minnesota is infested with Oak Wilt. Transporting firewood out of this area risks spreading this forest disease.

The unseasonably warm winter extends the 'don't prune' window and it probably starts in March for 2024. 

 ACD was a recipient of the MN Department of Natural Resources ReLeaf Community Forestry Grant to help efforts to manage Oak Wilt and EAB in Anoka County. A variety of tree species will replace those affected by Oak Wilt in the Anoka Nature Preserve (ANP), including treating Common buckthorn in 2024-25 to free up space for new trees to be planted in 2026. Ash trees at Kings Island in the City of Anoka will be removed in early 2024 and new trees will be planted in 2025. Planting at both of these sites will be completed with the help of volunteers. If you have interest in helping out as a volunteer, sign up here!

For more information contact Logan Olson, Restoration Technician, at This email address is being protected from spambots. You need JavaScript enabled to view it..

Believe it or not, winter is a busy time of year for ACD's field crew. This winter, our buckthorn crew has started a five-year restoration project at Lamprey Pass Wildlife Management Area (WMA) in Columbus, MN. A popular destination for waterfowl hunting, Lamprey Pass is the second largest WMA in the North Metro. 

The Lamprey Pass site is currently overrun with common buckthorn, a large invasive shrub that crowds woodland understories and shades out native plants. ACD's crew is working hard to remove this invasive plant from the WMA, creating a more open habitat which will benefit native plant species and make the woodlands more hospitable for hunters. The images above and below demonstrate the impact of clearing buckthorn on the site. For more information about treating buckthorn, contact Logan Olson, Restoration Technician at Logan.Olson @AnokaSWCD.org 

Root boring weevils are a method of biocontrol that target knapweed without affecting surrounding native plants. As larvae, root weevils burrow into the roots of spotted knapweed and feed on them throughout winter and spring, leaving the plants dead or weakened. The weevils we released at ANP were adults who will lay their eggs at the base of the plants through early fall and hopefully begin to weaken the population of spotted knapweed within the preserve.

ANP was a promising candidate for root weevils biocontrol because the site has a large, dense population of spotted knapweed, and the weevils will not be disturbed by mowing or other land management activities. It can take several years to see the effects of the weevils, and the site will be monitored to see if they have been established. The weevils were provided by Monika Chandler from the MN Department of Agriculture, who delivered them in a sealed paper cup where they were kept refrigerated or in a portable cooler until the time of their release later in the afternoon. 

Article and photos provided by Sally Herman, Seasonal Technician with ACD  

Earlier this year, the MN Dept of Agriculture (MDA) added Amur Silvergrass (Miscanthus sacchariflorus) and Winged Burning Bush (Euonymus alatus) to the Restricted category of the state noxious weed list. It is unlawful to sell or propagate Restricted plant species and landowners are encouraged to manage their spread.

Amur silvergrass has been used as an ornamental plant in the US for over a century. It forms dense colonies that can aggressively outcompete native species. Consider replacing this species in your landscaping with showy native grasses such as little bluestem (Schizacharium scoparium), yellow prairie grass (Sorghastrum nutans), or prairie dropseed (Sporobolus heterolepis).

Winged burning bush was also introduced to the US as an ornamental shrub. While its dense thickets made it a popular hedgerow plant, they also enable it to crowd out native vegetation when allowed to spread into natural areas. Winged burning bush produces many seeds which are distributed by wildlife, allowing it to easily spread over long distances. Consider replacing this species with native shrubs such as serviceberry (Amelanchier alnifolia), chokecherry (Prunus virginiana), and button bush (Cephalanthus occidentalis).

Learn more about identification and management of these invasive species with these MDA resources on Amur Silvergrass and Winged Burning Bush. 

ACD Contact: Carrie Taylor, This email address is being protected from spambots. You need JavaScript enabled to view it., 763.434.2030 x190

Lymantria Dispar is an invasive moth formerly known by the common name Gypsy Moth. Last year, the Entomological Society of America officially changed the common name for this invasive species to the Spongy Moth. Romani people, Europe's largest ethnic group, generally consider the common name "Gypsy Moth" to contain a racial slur. The Entomological Society of America states that "while the use of an ethnic slur is enough reason to stop using a common name, the former common name was doubly inappropriate in that it linked a group of people who have been treated as pests and the targets of genocide with an invasive pest insect that remains targeted for population control and eradication, all of which combined to have dehumanizing effects for Romani people."  

The new common name for Lymantria Dispar, the spongy moth, refers to the insect's light brown, fuzzy egg masses. This new name also aligns better with other countries common name for this invasive species. This moth is known for defoliating deciduous forests while in their caterpillar form. This repeated defoliation causes stress and can leave trees vulnerable to other diseases and pests. Spongy moths were introduced to the United States from Europe in the nineteenth century. They have spread from their initial location in Massachusetts westward, in both the United States and Canada. 

Since 2004, Minnesota has been a member of the U.S. Forest Service's Slow the Spread (STS) program. Cook and Lake Counties are the only places with reproducing spongy moths in Minnesota. Parts of Eastern Minnesota are within the transition zone, and most of the state is still listed as an uninfested zone. Currently, Anoka County is still within the uninfested zone, but the spread of the spongy moth is occurring at a rate of 3 miles per year.

Non-native Phragmites is a highly invasive plant that can invade wetlands and shorelines, outcompete native vegetation, and degrade wildlife habitat. Fortunately, most of the infestations in Minnesota are small and there is hope that the invasive grass can be controlled.

Coon Creek Watershed District and ACD staff first detected non-native Phragmites in Anoka County in 2018 along the Ham Lake shoreline. The 2,500 square foot stand was herbicide treated in fall 2018 and mowed in January 2019. No Phragmites was found at the Ham Lake site in 2019 and 2020. One sprout of Phragmites was found in 2021 and dug up.

Additional non-native Phragmites infestations have been found and verified by UMN in Anoka County. The treatment success at Ham Lake inspired staff to continue additional efforts to control non-native Phragmites. In 2019, the Anoka County AIS Prevention grant paid for treatment of 14 additional Phragmites sites that were detected in the 2019 growing season.

The MN Department of Agriculture Noxious Weed grant provided funds for the Metro Counties to collaborate and treat over 80 sites in 2020 and 2021. The University of MN, MN DNR, and MN DOT are also tracking and treating additional sites throughout the state. Sites will continue to be monitored to determine treatment needs.

Photo below shows a stand of Phragmites at a site in Anoka County being monitored in 2020. Follow up treatment occurred in September 2021.

Find more information and distribution maps can be found at the links below:

https://www.eddmaps.org/distribution/viewmap.cfm?sub=59038

https://www.dnr.state.mn.us/invasives/aquaticplants/phragmites/index.html

https://maisrc.umn.edu/phragmites

Early fall can be a great time to identify invasive species around your property. Invasive species can potentially outcompete native plants. Controlling invasive species can help increase native plant diversity and create better habitat for local wildlife. It also help stop the spread of invasive seeds to your neighbor's property and other natural areas. The first step in managing invasive species on your property is by identifying them. Three species to look out for this time of the year are:

Canada Thistle is an aggressive perennial that produces many seeds. They are best identified by their wavy spiny/toothed margins that can be prickly if walked through. Most of their purple flowers have turned into a ball of white fluff by this time of year

Purple loosestrife is listed as a MDA prohibited noxious weed that grows along shoreland areas. Purple loosestrife can make it difficult to access open water and the dense root systems can even change the hydrology of wetlands. Leaves are lance-shaped with smooth edges and grow up to four inches long. They are usually arranged in pairs opposite each other on the stem, and rotated 90 degrees from the pair below. Individual flowers have five or six pink-purple petals surrounding small, yellow centers. Single flowers make up flower spikes, which can be up to one foot tall. This is a great time to look for the bright purple flowers along your shore.

Common tansy is also an invasive species that is currently flowering. The flowers are bright yellow and button like arranged in a flat-topped cluster. The leaves look fern like with reddish-brown stems. It is very common invasive species in the arrowhead of Minnesota. This quick spreading species can greatly impact landscape restoration efforts.

You can reach out to ACD if you want to confirm an invasive species on your property or want advice on how to manage the invasive population. 

Owners of loved and valuable pets sometimes have a microchip implanted to help recover them if they are lost or stolen. The same technology is now being used to help the Anoka Conservation District remove destructive carp from lakes.

We recently added microchip PIT tags to 187 carp in Typo Lake (Linwood Township). Those carp are now telling us when and proportionately how many carp are visiting baiting stations in the lake. An underwater sensor detects the carp when they are near the bait. A floating, solar-powered control unit uploads that data to the internet. This allows us to spring the nets around the bait at times that are likely to catch the most carp.

Graph: Number of PIT tagged carp visiting baited net stations over 7 days. Note the increase over time and the peak just after midnight. 

Siberian peashrub (Caragana arborescens) is a restricted noxious weed in Minnesota. It has a background similar to Common Buckthorn, commonly found in hedge groves, shelterbelts, and wildlife plantings. Siberian peashrub is not as common as buckthorn but is becoming more prevalent throughout the state. These plants have an extensive root system and the ability to self-reproduce to create new infestations. Last year, infestations in Bunker Hills regional park were surveyed and mapped by ACD staff. These maps were used during three days of targeted treatment by ACD this winter. After three days, ACD completed cut-stump treatment on 14 infestations which totaled approximately 3.5 acres.