Origin and Habitat: Encephalartos transvenosus occurs intermittently over a large area in the Limpopo Province, (northern Transvaal), South Africa. In the south the distribution starts in the northern parts of the Drakensberg mountain range. Further northwards a large isolated subpopulation is found in the Modjadji Nature Reserve. The distribution is then taken up in the Soutpansberg mountains. It extends over most of this mountain range and continues further east to the middle of the Thohoyandou area. This species is very abundant in several locations, including the remarkable cycad forest at Modjadji, the only cycad forests in Southern Africa. The Modjadji cycad forest is truly an awe-inspiring place. It is estimated that it contains between 10,000 and 15,000 fully grown E. transvenosus (the largest concentration of a single species of cycad anywhere in the world), with some individuals reaching the astounding  25-40 ft (8-12 m) and there are some other very large subpopulations.
Altitude range: 1,970-4,920 ft (600-1,500 m) above sea level.
Habitat and Ecology: All localities of E. transvenosus are on mountain mistbelt zones. Plants grow in tall grassveld and mixed bushveld, mainly on steep rocky slopes facing southeast. A rainfall greater than 20 in a year is experienced in the region, with frequent mists providing cool, humid summers. The region is free of frost. Porcupines are known to ringbark cycads in some areas and if accessible, the cones are destroyed by the porcupines when they strip the cones of their succulent cone scales. Baboons occasionally break off the immature cones. The Leopard Magpie moth larva is capable of destroying the newly sprouted leaves of a cycad. Certain seed-eating snout beetles of which there are a number of species, can in the case of a heavy infestation, destroy an entire seed crop. The attractive, brightly colored seeds attract squirrels, baboons, monkeys and dassies. Some birds such as louries, parrots and trumpeter hornbills are also attracted to the seeds. Only the soft tissue covering the seed is eaten and the kernel is then discarded. Plants are removed from the wild by collectors and there is loss of habitat in some places.

Description: Encephalartos transvenosus is a robust, tall-growing arborescent cycad from the genus Encephalartos. It looks like a palm tree with a crown of fairly straight, shiny green, spiny leaves, but producing cones, often resembling those of a pine but far larger. They are dioecious which means male and female cones are produced on separate plants. Mature leaves are straight and flat, with broad leaflets tending to droop away from the rachis. The new leaves are light green covered with fine brown hairs, while the mature leaves dark green and glossy. Leaflets overlap, and carry 3-6 spines on both margins, and basal leaflets gradually reduce to prickles, although leaving some clear petiole. It is thought to be closest to Encephalartos paucidentatus, which has narrower, clearly spaced and mostly entire leaflets.
Derivation of specific name: The species name transvenosus refers to the fine network of veins between the main veins. These can be seen when the leaf is held up to the light.
Stem: Stout erect, generally unbranched, occasionally branched after injury to crown, up to nearly 12 m tall (many between 4-7.5 m), 40-45 cm in diameter deeply scored in a netted pattern, apex of stem with some brown wool. Typical of the species is the appearance of numerous dormant buds along the base of the stem.
Leaves: 150-250 cm long, dark green, highly glossy, flat (not keeled) in section (opposing leaflets inserted at 180° on rachis). Petiole fairly short straight, with no prickles densely tomentose at first, glabrescent, except for pulvinus. Leaf-base collar not present. Rachis yellowish, straight, stiff, recurving towards apex, not spirally twisted. Leaflets preading more or less at right angles to rhachis, broad, lanceolate or ovate, often slightly curved, strongly discolorous, somewhat overlapping upwards, not lobed smooth on upper surface, with unevenly prominent veins on lower surface. Margins flat; upper margin lightly toothed (1-3 teeth); lower margin lightly toothed (1-3 teeth). Median leaflets 16-25 cm long, 25-45 mm in width. Those at the base are reduced to prickles.
Cones: 1-4 borne together on short stout tomentose peduncles.
Pollen cones: Ovoid to subcylindric, yellow, 30-40 cm long, 13-15 cm in diameter, obtusely rounded at base and apex; median scales 4-4-5 cm long, 2-5 cm broad with sharp lateral ridges.
Seed cones: Massive, oblong-oval in outline, yellow, 50-80 cm long, 20-30 cm in diameter, weighing up to 34 kg and are very handsome in the heart of the big green leaves.
Seeds: Oblong, 40-50 mm long, 20-27 mm wide, sarcotesta brilliant orange-red.

Cultivation and Propagation: As a garden subject, Encephalartos transvenosus is the tallest and one of the most spectacular of all cycad species. With dark glossy green leaves, the seedlings grow rapidly, developing into an attractive garden plant with 1 m long leaves in four to five years. This is one of the fastest growing cycads and responds well to cultivation provided it has a well-drained soil, frost-free conditions and regular watering during the dry months. It is an adaptable plant well suited to warm temperate and subtropical climates. It is more moisture-tolerant than most South African cycads. It can be grown in full sun without its leaves burning. When young they can be grown as a container plant and eventually transplanted into the garden. As a garden plant, this cycad will usually hold two or three crowns of leaves, all in good condition.
Soils: It prefer well drained, gritty soil with plenty of water, especially in dry weather.
Transplanting: This species transplants easily as a mature plant, although it is recommended to remove all of the leaves before doing so. This makes for easier handling and the plant will recover sooner due to less moisture loss.
Waterings: In cultivation prefers moist soil with good drainage for optimal growth. But it is eventually drought resistant. Irrigation systems can be detrimental to cycads, damaging the leaves and stems from the pressure of the water as well as over-watering.
Fertilization: Naturally undemanding for nutrients, it responds very well to regular applications of fertilizer. Growth can be greatly improved through the application of fertilizers. Most growers find that a fertilizer having an even NPK (Nitrogen, Phosphorus, Potassium) balance, and supplemental trace elements, provides a good start for cycads.
Exposure: It thrives and grows best in full sun or partial shade.
Wind tolerance: It prefers a sheltered position providing protection from the prevailing winds.
Hardiness: Frost sensitive.
Traditional uses: The seeds are a brilliant orange-red, and the thin fully ripe flesh surrounding the kernels is relished by the children of the village. In the past, the pith from the stem of cycads was removed, then enclosed in an animal skin, fermented and ground into a meal which was used to make bread.
Propagation: It may be propagated by seeds. They are among the easiest plants to germinate.

"Encephalartos transvenosus" Text available under a CC-BY-SA Creative Commons Attribution License. 14 Nov. 2005. 07 Mar 2021. </Encyclopedia/PALMS_AND_CYCADS/Family/Zamiaceae/29893/Encephalartos_transvenosus>

You might also like...

View different category...