Lake County Soil and Water Conservation District (Lake County SWCD) staff has been hard at work on City of Two Harbors property, removing a variety of terrestrial invasive species. Terrestrial invasives are plants that are not native to an area and have a tendency to out-compete more desirable native trees, shrubs, and wildflowers.
Japanese barberry is a newcomer to the Northland, and one of the worst that we could get. This thorny shrub spreads aggressively and completely takes over areas when left untreated. A large patch was recently identified by Lake County SWCD on the bike trail north of Super One, and last week SWCD staff began the long process of managing the plant. This involves hand-digging and pulling, as well as the use of a 400,000 BTU propane torch to burn the base of the plant. This species is not fire-tolerant, so burning the growth points at the base of the plant can be an effective means of control. More information will soon be available to Lake County residents regarding the importance of reporting and controlling Japanese barberry infestations.
Lake County SWCD staff has been working on Lighthouse Point and in Memorial Park, removing isolated patches of tansy along the paved bike trail, and replacing these patches with plugs of aggressive native species such as bee balm, small white aster, cup plant, and Maximillian sunflower. Large patches of Japanese Knotweed along Park Road are also being cut down, and will be treated later in the summer.
“Memorial Park, Lighthouse Point, and the trails that run through those areas are such assets to the City. Lake County SWCD feels it is worth being pro-active in controlling the invasive plants that are there before they take over the space,” said Dan Schutte, Lake County SWCD District Manager. “Folks in central and southern parts of Minnesota have completely lost the battle against these invasive species. Once they are established, there is really no going back to the diverse natural environment without spending enormous amounts of time, energy, and money.” That means that all of the birds, butterflies, and other animals that used to live in the area and use the native plants and trees would be gone, with little incentive to return. Buckthorn, honeysuckle, and reed canary grass are other aggressive invasive species found in the Lighthouse Point area. Lake County SWCD will continue efforts to manage invasive species at these sites throughout the summer, and is always looking for community members interested with helping inventory or control terrestrial invasive species in our area.
Aggressive small white aster plugs being planted in areas where tansy has been removed along the Memorial Park trail in Two Harbors in an effort to outcompete next spring's aggressive slew of tansy.
Lake County AIS Plan - Adopted August 2015, updated in 2018, subject to further updates
Lake County AIS Plan Appendix A - Lakes Summary from 2015
Lake County AIS Plan Appendix B - Lake County AIS Prevention Plan Partners
AIS Lakes Summary - Adopted August 2015 subject to updates
The MN DNR has put together a wonderful series of videos showing how to clean equipment to avoid spreading terrestrial invasive species: