Galeopsis bifida is a plant species in the genus Galeopsis . It is an annual plant native to Europe and Asia but now found in Canada and northeastern, Midwestern part of United States. It has other alternative names such as Bifid hempnettle,split-lip hempnettle and common hempnettle. Early botanists thought that its corolla resembled a weasel hence they gave the name Galeopsis to its Genus. It is often confused with other species such as Mentha arvensis

Mentha arvensis

Mentha arvensis is a species of mint with a circumboreal distribution. It is native to the temperate regions of Europe and western and central Asia, east to the Himalaya and eastern Siberia, and North America.It is a herbaceous perennial plant growing to 10–60 cm tall...

, Dracocephalum parviflorum and Stachys pilosa Nutt but its flowers shape and leaf's structure makes it distinguishable from the rest of the species.

Distribution

Galeopsis bifida naturally occurs throughout Canada,northeastern and Midwestern part of United States. It was also introduced in some parts of New Zealand and Canary Islands located just off the northwest coast of mainland Africa. It also has been reported in southeast, central and western Alaska. It is an important weed in the communities of Alaska..

Habitat and Ecology

Hempnettle mostly grow in disturbed sites, roadsides, gardens, agricultural lands, wet heaths and sometimes in the woods. It creates a dense mid-forb layer dominating the regular grass and low forbs. It utilizes limited nutrients and requires moist soil, usually prefers moderate levels of acid and basic soils..

Morphology

Hempnettle could grow up to 1 meter high depending on the type of area. Its leaves and flowers are hairy. Leaves are simple, 1 to 5 inches long, opposite, margins are serrate and ovate shaped pubescent on both sides. The stem is swollen below the leaf nodes. Its flowers could be in purple, white or pink and are terminal in axillary clusters.

Flowers and fruit

Its corolla is bilabiate meaning that it has two lips. An upper lip and lower lip, the upper lip has one lobe and the lower lip has three lobes covered with hair on the lower side of the lobe. They are bell shaped and bilaterally symmetrical. They range about half to three fourth of an inch. Pistil contains of two fused carpels, its stigma is two lobed. It also contains four stamens, two of which are long and two are short. Its style is solitary. Its flowering time is between July to September. Its fruit is a schizocarp and brown in color.
This plant is self pollinated. They have a capacity of producing up to 2,800 seeds which can remain dormant under soil for few years.Their seeds are large and are unable to adapt long distance wind dispersal, but it can be accomplished with the help of animals fur. Their germination occurs not that deep into soil. and it takes place within a month..

Usage

They aren't any medicinal uses through this plant but its oil obtained from the seeds is used as a polish for leather. On the other hand, these plants are very poisonous and could cause paralysis.. It has been declared noxious in Manitoba, Alberta, Quebec and some parts of Alaska..