Plant invasion a bit hairy
Last fall I noticed many green clumps of an unknown origin growing in my flower beds. I hoped that whatever it was would disappear with the coming of winter. Unfortunately, this did not happen and now there is an invasion of hairy bittercress.
The bittercress seems to be everywhere this year and I wondered how it arrived. Doing some research I found it can come with mulch or the seeds can be in a container plant you may have purchased or someone else nearby has a plant or plants and bittercress easily spreads.
The seed pods explode at the slightest touch so once some of the plants get a foothold, they are off and running. The leaf stalks grow from a basal rosette and can grow up to 4 inches long and are sparsely hairy.
Each leaf stalk has five to nine paired leaflets and the largest of these is at the top of the stalk. The flower stalks can grow up to 10 inches tall. The flowers are small, white, and have four petals and when they are blooming, the seed capsules are forming. The seed capsules are ½ to 1 inch long and an olive green color. This is when they can explode and spread.
The best way to eliminate this pest once it has flowered is to pull or hoe out the entire plant. Do this as soon as possible in the spring before the seeds have a chance to spread. Weed killers should also work but be careful when using around flowers.
Hairy bittercress came to us from Europe and Asia and seems to love being in the states, especially in disturbed soil and sunny areas where the soil is moist. Other names for hairy bittercress (Cardamine hirsuta) are snapweed, pepperweed, flick weed, and land cress.
Maryellen Walter is a Penn State Butler County Master Gardener.
