Got Nature? Blog

Early spring brings the emergence of new life in the forest. Unfortunately, not all that life actually belongs there. Several invasive plants are encroaching on woodlands and crowding out the desirable native plants we enjoy and wildlife depend upon for food and shelter. One of the characteristics of some invasive plants is early leaf emergence and growth, which allows us to scout for their presence more easily, while native species are still waking up from winter. Two species that start growing very early in the spring are garlic mustard and Asian bush honeysuckles. Both plants are rapidly greening up and growing as I speak. Look for the kidney to heart shaped leaves of garlic mustard on the forest floor. This biennial will soon be sending up flower stalks from the second season plants that will have white four-petaled flowers. The flower stalks can be up to three feet tall or more depending on the health of the plant and the quality of the growing site.

Early spring leaves of garlic mustard.

Asian bush honeysuckle is a medium to large bush that also inhabits the forest understory and edge or disturbed areas. Leaves and twigs area arranged opposite each other. If you slice the stems open, they are hollow inside with fuzzy brown or tan lining​. Flowers are yellow, white or even pinkish and tube-shaped. The fine twigs and stems have a light tan or gray-tan color. Leaves are rapidly expanding now, so they will be easily detected until our native plants catch up with leaf cover.

Early growth of Asian bush honeysuckle.

Controlling these plants helps native plants continue to thrive and provide habitat for our wildlife. Garlic mustard can be pulled from moist soil. If seed pods are present, remove the plants from the area and burn or bury them. Foliar herbicides like glyphosate products may be used to spray garlic mustard. If the plants have already set seed pods, the seed may become viable even if the plant has been sprayed, so removal may be the only effective treatment at that time.

Asian bush honeysuckle can be controlled in several ways, depending on the size of the plants. Small plants can be pulled from moist soil. Foliar sprays with herbicides like glyphosate can be effective. Large bushes may be cut and the stumps treated with a brush-killing herbicide. For any herbicide application, read and follow label directions.

Purdue University has invasive species information resources at FNR Extension and Indiana’s ‘Most Unwanted’ Invasive Plant Pests/Indiana Cooperative Agricultural Pest Survey (CAPS) Program.

Lenny Farlee, Sustaining Hardwood Extension Specialist
Hardwood Tree Improvement and Regeneration Center (HTIRC)
Forestry and Natural Resources, Purdue University