Most South Dakotans have heard of the common buckthorn weed that has been spreading through our state for decades. It gives a new meaning to the phrase “the buck stops here.” It was imported from Europe by early Americans, thinking it would have ornamental uses. It quickly established itself to North American soils by using birds to spread its unwanted seeds.
If common buckthorn is not removed the result is the shading out of native plants, reduce dplant diversity in the infected area, and a host for undesirable pests.
There is some evidence that common buckthorn affects the soil in a way to inhibit the growth of some native flora. Buckthorn unripened fruit is an overwintering host for the soybean aphid eggs. It is also an alternate host for alfalfa mosaic virus and crown fungus, which causes oat rust disease. Lastly, buckthorn is also considered to be a winter host for the newly arrived invasive spotted wing drosophila fruit fly, which attack and destroy strawberries, raspberries, and other soft fruits.
To identify common buckthorn, look for the following characteristics. It is a leafy shrub or a small tree. They have dark green leaves which are elliptical or ovate and vary from 1 ½ to 3 inches long. The twigs will have thorns at their tips. Bark and stems are brownish or grayish in color. Small, green-yellow flowers will appear in the late spring. The shrub will produce a round purplish black fruit. The fruit is not eatable and causes diarrhea in birds, hastening its spread. It will not grow in mowed or tilled areas but will populate in woodlands, ditches, fence lines, and other undisturbed areas. It commonly gets started where birds perch. If allowed to establish, it will take years of labor to eradicate it.
If you are lucky enough to have mature common buckthorn, wood carvers prefer the burnt red-orange dense heartwood. Wood turners can make beautiful colored turned art pieces. The straight stems make excellent walking sticks. When dried, the wood is very dense and makes a slow burning firewood.
Isn’t that an appropriate end to one of South Dakota’s most uninvited invasive plants?
There are control options for the common buckthorn. The best is to recognize the plant and eliminate it before it gets established. Young seedling can easily be pulled out by hand or dug out using a spade or potato fork. Medium size plants can be pulled out by wrapping a chain around the stem and pulling with an ATV or tractor. There are commercial pulling tools available that are effective.
Just cutting off the common buckthorn will later be discovered as a disaster. Lopping off the main stem will result in multiple stems in the following years and helping it become a better established plant. There are chemical options that are effective. Those options can be obtained by contacting the SDSU Extension Service or search the https://extension.sdstate.edu website. Just type in “buckthorn” in the search box.