Lepidium draba, former Cardaria draba
Hoary cress is a member of the Mustard family. The Latin draba is from Greek drabe = sharp, bitter. It produces numerous white flowers at the top of the plant which has given it the name of 'white-top'. The Danish name Hjertekarse alludes to Hjerte (Heart), since the seedpods are heart-shaped. The flowers serve as pollen and nectar sources for many insects, and livestock will usually eat hoary cress.
It is native to western Asia and eastern Europe, from where it has spread. Indicating seed may have been in the soil that was used as ballast for sailing ships. It is relatively rare in Denmark but is seen in some coastal areas.
In its native lands it was used as a culinary herb and as a substitute for pepper, and in medicine for diseases as scurvy and as a carminative.
It is a highly competitive weed, and it has become a serious problem in the United States. Idaho has listed hoary cress as a noxious weed.
photo 250508: grethe bachmann , Kalø, East Jutland