Stachys arvensis is a species of flowering plant in the mint family known by the common names field woundwort and staggerweed. It is native to Europe, Western Asia, and North Africa. It is known on other continents as an introduced species and widespread weed.
It grows in many types of habitat, including disturbed areas, and often in moist spots. It is an annual herb producing a branching stem up to about 60 centimeters in maximum height. The stem is squared in cross-section and it is covered in rough hairs. The oppositely arranged leaves have hairy, serrated or toothed blades up to 2 or 3 centimeters long which are borne on short petioles.
The inflorescence is made up of interrupted clusters of flowers borne in the axils of the leaf pairs. Each cluster has up to 6 flowers with pinkish corollas in hairy purple-tinged calyces of sepals.
This plant might be poisonous
How to get rid of:
It is best controlled in cereal crops as young seedlings using bromoxynil (eg Bromotril, or in Jaguar or Image) or suppressed by using Hussar (iodosulfuron). In other crops, trifluralin can control it, clopyralid can give reasonable knockdown of it when applied early enough, atrazine and simazine kills it, and it is also controlled by non-selective herbicides such as glufosinate and glyphosate.