Galeopsis species - Hemp-nettles

There are three species of these arable weeds in Lanarkshire. They usually require to be in flower to tell them apart.

They are all roughly-bristly with spear-shaped, coarsely-toothed leaves.

The calyx has five widely spaced, spine-tipped spines.

Galeopsis tetrahit - Common Hemp-nettle

Corolla 12-20 mm long rarely more than 1.5 times the length of the calyx. Central lobe flat at most only slightly notched and the dark markings fall well short of the tip. Record Galeopsis tetrahit agg. if not in flower.

Galeopsis bifida - Bifid Hemp-nettle

Central lobe flat notched, folded downwards towards the margins. The dark markings extend almost to the edge.

Galeopsis speciosa - Large-flowered Hemp-nettle

Overall bigger, stem swollen below nodes with yellowish-tipped glandular hairs.

The lower lobe has a bold purple blotch and the upper corolla usually yellow. 27-35mm and twice the length of the calyx.

Galeopsis bifida NS7163 14Aug2019 PW

Flower can be purple, mauve, white or (rarely) yellow. Differs from G tetrahit mainly in the lowest lobe of the flower, which is clearly notched, somewhat convex, and has the dark markings reaching close to the edge, or else the lobe uniform in colour.

Galeopsis bifida 30July2017 NS6257

Stem with conspicuous dense spreading hairs. Stem swollen at the leaf-junctions.

Galeopsis bifida NS5670 13Aug2017 PW

There is a notch in the lower lip, the edges are rolled over and the pink lines are close to the margin.

Galeopsis bifida NS5670 13Aug2017 PW

Galeopsis bifida NS7066 07Jul2018 PW

Stem with conspicuous dense spreading hairs. Stem swollen at the leaf-junctions. Flower purple, mauve or white, but not yellow (except in centre). Lowest lobe of flower not or scarcely notched and the dark lines on it not reaching the margin. Compare G bifida.

Galeopsis tetrahit 3Jul2017 NS9353

Galeopsis tetrahit NS5565 25July17 PW

Galeopsis bifida in the front and Galeopsis speciosa behind showing the difference in the flower and plant sizes.

Galeopsis bifida front, Galeopsis speciosa behind NS7163 14Aug2019 PW

Flowers usually yellow, white and purple and can be all yellow. Lowest lobe of flower not notched. Stem roughly hairy almost bristly and swollen at the leaf-junctions.

Galeopsis speciosa NS5872 29Sep2018 JW

Galeopsis speciosa NS7069 23Jul2016 MJP

Galeopsis speciosa NS5671 13Aug2017 PW