Ballota nigra has a very strong characteristic smell reminiscent of mould or damp soil, and can be recognised by its clusters of hairy, reddish-purple flowers. It can grow up to 1m (3ft 3in) tall.[6]
Stem and root
It has erect herbaceous stems, wooden and branched at bottom, covered by downy hairs.[6] The plant has a taproot system.
Leaves
The leaves are opposite and decussate, and range from oval-lanceolate to heart-shaped, with crenate or dentate border. They are dark green and usually pubescent, measuring 2–8cm by 2–6cm, and have a 1–3cm petiole. Upper face is wrinkled, with a net-like vein pattern.
Flowers
Black horehound flowers
The flowers are arranged in verticillasters, subspherical to one-sided, with 15–30 flowers. Each verticillaster consist of two condensed dichasial cymes in the axils of normal leaves.
Each flower has an actinomorphic calyx, length 9–10mm, width 7mm, made up of five sepals fused together in a tube with five teeths; and a labiate corolla of 12–14mm, ranging from pink to pale purple to withish. The corolla consist of a tube of about 6mm and two lips; the upper one slightly concave (like a hood) and externally hairy; the lower one glabrous, with two minor lateral lobes and a major central bifid lobe. There are four didynamous stamens, running parallel under the upper lip, with glabrous filaments and yellow anthers. The ovary is superior, with a single white style and a 2-parted stigma.[6][7]
Below the calyx there are five filiform bracts, 8mm long. The flowers are pollinated by a wide variety of different bee species.[7]
Fruit
Each fertilised flower produces a tetrad of black nutlets, cylindrical to ovoid, 2mm long, partially or fully covered by the calyx. The basal end is flat and attached to the receptacle, while the top end is rounded or pointed.
Taxonomy
The plant was described by Linnaeus in Species Plantarum (May 1753). The name Ballota comes from the Greek ballo (to reject), because of the strong offensive smell of the plant; cattle will not eat it. The specific name nigra could refer to the black colour of dried leaves.
Ballota nigra subsp. anatolicaP.H.Davis - Iran, Turkey
Ballota nigra subsp. anomalaGreuter - Greece
Ballota nigra subsp. meridionalis(Bég.) Bég. (syn. B. n. subsp. foetida(Vis.) Hayek) - central + southern Europe; naturalised in Sweden, Ukraine, Cyprus, Turkey, Argentina
Ballota nigra subsp. kurdicaP.H.Davis - Iran, Iraq, Turkey
Ballota nigra subsp. nigra - southern and central Europe, Great Britain, Sweden, Caucasus, Iran, Turkey; naturalised in Belgium, New Zealand, Argentina
Ballota nigra subsp. sericea(Vandas) Patzak - Albania, Macedonia, Greece
Ballota nigra subsp. velutina(Posp.) Patzak - Slovenia, Croatia; naturalised in Argentina
Etymology
The common name comes from the Old English words har, meaning "downy or hoary", and hune, meaning the plant itself. This name refers to the hairs that give the herb its distinctive appearance. In modern times, some alternative medicine practitioners have referred to the plant as "seed of Horus"[8] and claiming that horehound takes its name from Horus, the Egyptian sun god.
Habitat
Ballota nigra is a nitrophilous plant; it grows in ruins, fallows, and hedges at elevations up to 1300 m. It prefers loose, calcareous (alkaline) soils. It tolerates temperatures as low as -5°/-10°C.
Uses
Usually the plant is used dry and harvested when blooming. Syrups can be made from fresh plants.
1 2 Blamey, Marjorie; Grey-Wilson, C. (1989-01-01). The Illustrated Flora of Britain and Northern Europe. London: Hodder & Stoughton. p.336. ISBN0-340-40170-2.
Conti, Fabio; Carlo Blasi; Alessandro Alessandrini; Giovanna Abbate (May 2005). An annotated Checklist of the Italian Vascular Flora. p.60. ISBN88-7621-458-5.
This page is based on this Wikipedia article Text is available under the CC BY-SA 4.0 license; additional terms may apply. Images, videos and audio are available under their respective licenses.
