Encephalartos hirsutus – Hurter and Glen (1996)
xxx Cycad (Eng), xxx Broodboom (Afr)
Category: Threatened & Protected
The trunks of Encephalartos hirsutus are decumbent and up to 3.5m or rarely 4.2m long. It is 350mm to 400mm in diameter with persistent leaf bases with a golden, densely tomentose (hairy) crown, turning greyish with age.
The numerous leaves are arranged in a dense crown, glaucous, subsessile and rigid with recurved apices. They are 1.1m to 1.2m (-1.4m) long. The petiole is bulbous at the base, tomentose (hairy) and up to 130mm long. The rachis is tomentose, becoming subglabrous with age.
The pinnae are inflexed, with entire margins and the veins are raised on the abaxial surface. The leaflets are directed towards the apex of the leaf at an angle of about 40° to each other. The upper margins overlap with the lower margins of the adjoining leaflets. The basal leaflets are gradually reduced in size but not to a series of spines. The median leaflets are 130mm to 170mm long and 20mm to 24mm wide, narrowly elliptic and somewhat sickle-shaped, gradually acuminate with acute and pungent apices. They are decurrent (turning downward) basally on the rachis with the apices somewhat turned towards the leaf apex.
The cones are dimorphous, waxy bluish-green, glabrous and with smooth scale facets. Up to 5 male cones per stem were seen. They are narrowly ovoid, about 500mm long and 90mm in diameter with peduncles about 120mm long. The exposed faces of the median microsporophylls (male cone scales) are rhombic, about 29mm wide, 30mm long and 7mm high, with the central facet flat or slightly concave. The female cones are ovoid and 1 to 3 per trunk were observed. They are about 400mm long and 350mm in diameter, appearing sessile but with a peduncle up to 60mm long, hidden amongst cataphylls in the trunk crown. The median megasporophylls (female cone scales) are rhombic with four lateral and one central facet, about 50mm wide, 44mm long and 15mm high with the central facet a third of the horizontal diameter of the bulla. About 200 seeds are produced per cone. The sarcotesta is orange-red and the kernel is 30mm to 35mm long and 15mm to 18mm in diameter, ellipsoid in shape, round and smooth.
Distribution & Habitat
Plants grow exposed on south-east facing quartzite cliffs in moist semi-deciduous mixed scrub where observation is often obscured by the dominant Androstachys johnsonii (Lebombo ironwood) trees. At the type locality plants grow exposed on a dry south-facing cliff in association with Androstachys johnsonii, Adenia spinosa (“doringrige bobbejaangif”), Barleria bremekampii and Eragrostis superba (sawtooth lovegrass). The rainfall of some 350mm to 650mm per annum occurs in summer. Over the distribution range of this species, Encephalartos transvenosus is the only other Encephalartos species occurring nearby.
Cultivation & Propagation
E. hirsutus can be treated much the same as E. eugene-maraisii, E. dolomiticus, E. dyerianus and E. middelburgensis, given that the species are related and have a similar habitat. Like all cycads they prefer well drained soils. Plants grow well in full sun. Propagation is by seed.
E. hirsutus was recently described as a new species (Hurter & Glen 1996) and at present is known only from three widely separated localities in the Northern Province of South Africa. The specific epithet hirsutus means “covered with hairs”. Plants of this species were formerly referred to as Encephalartos “decurrens”.
E. hirsutus superficially resembles E. eugene-maraisii, E. lehmannii, E. princeps, E. dolomiticus, E. dyerianus and E. middelburgensis in its stiff, pungent and glaucous leaves. However, vegetatively it is easily distinguished from all six species by the decumbent habit of the trunk, decurrent bases of the leaflets and the raised veins on the abaxial surface of the leaflets. The morphology of the leaves in E. hirsutus is very distinctive. The leaflets are deflexed, overlap with upper margins over the lower margin of the adjoining leaflets and the proximal part of the leaflet bases are shortly decurrent (turning downward), a character not yet observed elsewhere in the genus.
In E. eugene-maraisii, E. dolomiticus and E. princeps the leaflets are also inflexed and overlapping but the veins of these three species are not raised on the abaxial surface of the leaflets and the leaflets are subsessile on the rachis. E. lehmannii and E. dyerianus also differ from E. hirsutus in that their leaflets are subsessile and overlap with the lower margins over the upper margin of the adjoining leaflets, although their median leaflets usually do not overlap. E. middelburgensis differs strikingly from E. hirsutus in its subsessile, strongly succubous leaflets. Profound differences are observable in the cones of E. hirsutus.