Minnesota has several species of native honeysuckle but beware - there is a chance the honeysuckle you have at home may be one of the four non-native species of bush honeysuckle that are invasive in a Minnesota landscape! Here’s how to tell the difference and what to do about this invasive plant.

The invasive honeysuckle species taking over Minnesota woodlands crowds out native plants in much the same way as buckthorn. The plants send out chemical signals to inhibit the growth of nearby plants, have an early leaf out in the spring that shades the plants that do start to grow, and produce berries that have little nutritional value to birds. Areas with large amounts of honeysuckle make attractive bedding sites for deer and consequently, the deer ticks that cause Lyme disease come right along with them! The invasive species to watch for include the Amur (L. maackii), Tartarian (Lonicera tatarica), Morrow’s (L. morrowii), and Bell’s (L. x bella) honeysuckles. 

If you are looking to eradicate invasive honeysuckles in your landscape, your first step would be to identify it. You don’t necessarily need to know which specific species it is. A good rule of thumb to rule out any of the invasives over our native honeysuckles is to look at the stems. If a plant over 2 years old has a hollow brown pith (core) it’s one of the four invasive species. So, get snapping and check your honeysuckles!

In the spring when the ground is moist and right after leaf formation, you can try manually pulling or digging honeysuckles out. Just be sure you get the entire root crown removed. If you need to, you can spray the leaves with glyphosate but you must do it before other surrounding plants leaf out. Just as with buckthorn, the fall is the most effective time to treat with herbicides since plants will be pulling nutrients down into their roots. After cutting the stumps down to the ground, immediately spot treat the top with glyphosate or triclopyr as directed on the product label. Another effective treatment is using basal bark spray with triclopyr ester. If you are able to do prescribed burning, that will kill the top of the shrubs and seedlings but you will likely have to do repeat burns. 

To prevent the honeysuckle from returning, replant the area as soon as possible. winterberry, pagoda and gray dogwoods, common elderberry and black chokecherry are good substitutes for filling your spaces back in. 

If you plan to replace your invasive honeysuckles with natives or just want to add some to your yard, there are two types of honeysuckles recommended by the University of Minnesota Extension to plant in Minnesota.  The Southern bush honeysuckle (D. sessilifolia) which is a zone 4 plant and our native Northern bush honeysuckle (Diervilla lonicera) that is hardy to zone 3. These honeysuckles have several attractive features. Both tend to be adaptable to varying light levels as well as soil types, are good for erosion control and neither has serious pest problems. So, feel free to plant honeysuckles in your yard just be cautious about the type you are introducing into your 

garden.

Resources:

https://extension.umn.edu/trees-and-shrubs/bush-honeysuckle

https://www.dnr.state.mn.us/invasives/terrestrialplants/woody/bush-honeysuckles.html

https://extension.umn.edu/my-minnesota-woods-news/scouting-invasives-species-fall

https://mipncontroldatabase.wisc.edu/search?name=Morrow%27s_honeysuckle&habitat=7&season=8

https://news.wisc.edu/invasive-shrubs-increase-spread-of-tick-borne-disease/

Photo Credits: Amanda Drews (1-5)