Ajuga reptans


Ajuga reptans is commonly known as bugle, blue bugle, bugleherb, bugleweed, carpetweed, carpet bugleweed, and common bugle, and traditionally but less commonly as St. Lawrence plant. It is an herbaceous flowering plant, in the mint family, native to Europe. It is invasive in parts of North America. Ajuga reptans is also a component of purple moor grass and rush pastures, a Biodiversity Action Plan habitat in the United Kingdom.
Ajuga reptans has dark green leaves with purple highlights. It is a spreading and dense ground cover. The leaves grow tall, but in the spring it sends up tall flower stalks bearing many purple flowers. The flowers are frequently visited by flies, such as Rhingia campestris.

Description

Ajuga reptans is a sprawling perennial herb with erect flowering stems and grows to a height of about. The stems are squarish with hairs on two sides and the plant has runners that spread across the surface of the ground. The purplish-green, stalked leaves are in opposite pairs. The leaf blades are hairless and are elliptical or ovate with a rounded tip and shallowly rounded teeth on the margin. The inflorescence forms a dense raceme and is composed of whorls of blue flowers, each with dark veins on the lower lip. The calyx has five toothed lobes and the corolla forms a two-lipped flower about long with a short tube. The upper lip of each flower is short and flat with a smooth edge and the lower lip is three-lobed, the central lobe being the largest, flat with a notched tip. There are four stamens, two long and two short, which are longer than the corolla and are attached to the tube. The ovary is superior and the fruit is a schizocarp with four chambers.

Habitat

Woods and rough pastures.

Distribution

Common in Ireland, and throughout Great Britain.

Pollination

The species is monoecious, with male and female flowers on the same plant. Pollination is by bees or Lepidoptera.

Uses

Grown as a garden plant it provides useful groundcover. Numerous cultivars have been selected, of which 'Catlin's Giant' has gained the Royal Horticultural Society's Award of Garden Merit.
Bugle is also known as "carpenter's herb" for its supposed ability to stem bleeding.
Bugle is a primary nectar source of the pearl-bordered fritillary and the small pearl-bordered fritillary. It is a secondary nectar source of the brimstone, chequered skipper, common blue, cryptic wood white, dingy skipper, Duke of Burgundy, green-veined white, grizzled skipper, heath fritillary, holly blue, large blue, large skipper, large white, marsh fritillary, orange-tip, painted lady, small white, and wood white butterflies.
Ajuga reptans herb has been used in traditional Austrian medicine internally as a tea for the treatment of disorders related to the respiratory tract.