Land Plants - invasive

Nipplewort (Lapsana communis) on May 31, 2022

Originally reported as Garlic Mustard (Alliaria petiolata)

Submitter has sample

Description of specimen

Description? It’s all over my yard!!!!


Thank you for the report, Stephanie!
From the picture, this actually appears to be nipplewort (Lapsana communis), a common garden weed. While not native, it generally is not nearly as much of a threat in sensitive areas as garlic mustard is. Nipplewort is easy to confuse with garlic mustard. The leaf shape is similar, but adult garlic mustard leaves tend to be a bit more triangular. Also, 2nd year (bolting) garlic mustard currently has white flowers and seed pods forming (upright cylindrical siliques) and nipplewort is either still bolting or has yellow ray flowers. This would be a crucial find though if confirmed garlic mustard. Thank you so much for the report, and please keep your eyes out--you never know where pesky priority weeds will pop up!

To control nipplewort, you will want to mow and/or hand-pull before the plants start to flower and set seed. To control with mowing, you will need to mow regularly, as plants will re-grow and re-flower. Hand-pulling is more effective, but you will need to monitor the area and pull plants several times every year to diminish the soil seed bank. Herbicides are also effective.

Thanks again for your report!

Sarah Hamilton (she/her)
Native & Invasive Plant Specialist
503.949.6832 (work cell)

Sarah Hamilton
June 1, 2022, 9:17 a.m.