Recap of the 2012 Upper Midwest Invasive Species Conference

Recently, I joined a remarkable assemblage of natural resource professionals, academics, government agencies, business professionals and citizens for the 2012 Upper Midwest Invasive Species Conference (UMISC) in La Crosse, Wisconsin.   It was an outstanding opportunity to learn about challenges for managing the spread of invasive species in aquatic and terrestrial systems with three days filled with plenary sessions, workshops, poster sessions and field trips.

The Forest Pest Field Trip Was An EYE OPENER

On Monday afternoon, folks jumped on the bus travelling to nearby sites located on both sides of the Mississippi River.   It was amazing to see so many invasives in the area and to learn about the impacts to the ecosystem.

The first stop at New Salem, Wisconsin to visit a 60 acre site of American Chestnuts infected with Chestnut Blight using a natural virus.  Established in 1880, this site has been intensely studied by scientists looking to reinstate this majestic tree into Americas forests.

Annosum root rot was the feature for the second stop.  We enjoyed a short hike through a pine plantation to look at the ‘popcorn-like’ fruiting bodies of the fungas, dead pine trees and learned about treating stumps with a fungicide (Sporax).    When we returned to the bus, we cleaned the dirt off our boots, and sprayed them with alcohol to prevent movement of spores.

Oriental bittersweet, Celastrus orbiculatus,  a native plant from China was an interesting stop.   Oriental bittersweet is a vine, that  outcompetes native vegetation and has the ability to climb into the crown of trees.  The vines are substantial in size (up to 4” at the base) and the increased weight can lead to broken branches, and it is common to have trees uproot during high winds or heavy snowfalls.     There is concern because Oriental bittersweet is displacing our native American bittersweet (Celastrus scandens) through competition and hybridization.   During our tour, songbirds were very active in the thicket of bittersweet eating berries, and dispersing seeds as they travel.

Great River Bluffs State Park was the final stop  and visiting a site infested with Emerald Ash Borer exceeded all expectations.   Participants were able to look at ‘S’ shaped galleries, larvae, classic ‘D’ shaped exit holes, and woodpecker damage on  ash trees growing along the trail.  The site is being treated using biological control methods, and suggestions for management were part of the conversation.

On the bright side:

During Tuesday’s luncheon, the MN Invasive Species Advisory Council (MISAC) awarded the Carol Mortensen Invasive Species Awards.  Honors for individual achievement to Marsha Watland, for her work with the Cooperative Weed Management Area in Becker County.   The Forest Pest First Detector Program received the Carol Mortensen Invasive Species Award for Team Achievement.  Members of the Forest Pest First Detector Program include:  Angela Gupta-University of Minnesota Extension, Brian Aukema-University of Minnesota, Dean Herzfeld-University of Minnesota Extension, Gary Wyatt-University of Minnesota Extension, Gary R. Johnson-University of Minnesota, Jeffrey Hahn-University of Minnesota Extension, Kathy Kromroy-Minnesota Department of Agriculture, Robert Koch-Minnesota Department of Agriculture and Ken Holman-Minnesota Department of Natural Resources.  Congratulations everyone!

Special thanks to the conference organizers and sponsors for the fabulous conference—it was great learning!

Julie Miedtke is an Extension forester in Itasca County. She's based in Grand Rapids.

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  1. A very interesting article. How can you tell the difference between Oriental Bittersweet and American Bittersweet?

    1. Hi Gretchen. The best way to tell the two species apart is by the location of their fruit: Berries of Oriental bittersweet are in the leaf axils (where leaves join the stem), but berries of American bittersweet are in terminal clusters. This is illustrated and explained in more detail in this fact sheet from the US Geological Survey (PDF). There are also slight differences in the color of the fruit capsule, which covers the berries, as explained in this guide from the MN Department of Agriculture: Bittersweet Differences.

      Hope this helps.