Description
The stems of E. heenanii are well-developed and
suckering or branching from the base. Mature trunks are erect or
become procumbent with age. They are up to 3m long and 400mm in
diameter. The cataphylls are linear-lanceolate, often persisting
in a dry brittle form on the upper half of the trunk and are
very densely woolly with long golden brown hairs in the crown.
Leaves are 1m to 2m long, the rachis is incurved
and often slightly twisted at the apex, giving a "cup-like"
appearance to the plant's crown. The petiole can be up to 200mm
long and is round in cross section.
Median pinnae are succubously orientated,
ascending in the plane of the rachis and markedly reflexed from
the rachis. Leaflets are oblong-lanceolate in outline, 100mm to
150mm long and up to 20mm broad. The margins are entire or have
1 to 2 teeth. The lower leaflet surface has prominently raised
veins and while the upper surface often has small wart-like
protuberances. Lower leaflets are reduced but not to a series of
prickles.
Male cones are usually single or in groups of 2
to 4. They are sub-cylindrical in shape and pedunculate. They
are 270mm to 300mm in length, 120mm to 180mm in diameter and
covered with dense brown wool. Cones are seldom glabrous. The
male cone is similar in appearance to the female cone. A single
female cone is usually produced and rarely 3. It is pedunculate,
broadly ovate and 200mm to 350mm long, 170mm to 200mm in
diameter and covered with dense shaggy golden hair but is often
a glabrous yellow.
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Female cone |
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Male cones |
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Seeds |
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Leaf detail |
Distribution & Habitat
This species is known with certainty from a very
small mountainous area on the border between Swaziland and the Republic of South
Africa. It grows in open grassland on steep slopes at an altitude of about
1500m. The climate is hot in summer and cold in winter. The area gets summer
rainfall of 1200mm per annum.
Cultivation & Propagation
This species has little horticultural potential and
is notoriously difficult to cultivate. Mature plants seldom survive
transplanting and desiccate easily after removal. Plants are also prone to
fungal attack after transplanting. Seedlings are rare in trade, due to the fact
that plants seldom cone in cultivation. Plants are rarely seen in cultivation
and will probably always be a sought after collectors item.
Notes
The Makonywa, Ngwenya and Big Buffalo ranges form
part of the most eastern outliers of the south eastern Transvaal Drakensberg.
They are home to many endemic animal and plant species, including three of
southern Africa's rarest cycads, Encephalartos paucidentatus, E.
laevifolius and E. heenanii. The first indications of the latter
species' existence came from the exploration work of Mr. Denis Heenan in the
Piggs Peak district of Swaziland in 1969. The new taxon was found growing in
close proximity to large populations of E. paucidentatus and E.
laevifolius, and the first thought, which could not be ignored, was that it
could be a hybrid between these two unlike species. No supporting evidence for
this idea was found, however, and the lack of fresh cones hampered the
description of the species. It was not until 1971 that patient fieldwork by Mr.
Heenan and his son David, were rewarded with the discovery of fresh cone
material, which were sent to the late Dr. A Dyer at the then Botanical Research
Institute. The description of E. heenanii was published in 1972 and
honours the role played by Mr. Heenan in its discovery.
This species has clear affinities with the E.
transvenosus / E. paucidentatus group. It shares similar
characteristics, although the plants are much smaller in stature. E. heenanii is
probably most closely allied to E. paucidentatus and several natural hybrids
between the two species have been noticed. The two species share such
characteristics as the reflexed leaflets (in some E. paucidentatus
specimens at least) and the prominently raised veins on the lower leaf surface.
The relationship of E. heenanii with plants from the Lebombo Mountains east of
Stegi in Swaziland needs some investigation. These plants have inflexed
leaflets, densely golden woolly cataphylls and the veins are also prominently
raised on the leaflet abaxial surface, but the leaves are straight in comparison
with the characteristic incurved leaves of E. heenanii.
It appears as if this species was never abundant and
illegal collecting, even in the years before formal description, has reduced
numbers in the wild to near extinction. Plants are presently conserved in the
Somgimvelo Nature Reserve (RSA) and the Malolotja Nature Reserve in Swaziland.
During a survey in 1985, it was found that fewer than 500 plants existed in the
wild. Few cycads have captured the imagination of collectors as E. heenanii
has. It appears as if the inaccessibility of the terrain is no deterrent to
poachers who even hire helicopters to remove mature specimens. It is a sad state
of affairs that there are more mature specimens of this species in cultivation
than in nature. This species must be considered as endangered and close to
extinction by conservation authorities. This is mainly due to the taxon's
severely restricted distribution, intensive pressure from collectors, its
inability to reproduce sexually, inter specific hybridization, encroachment on
it's habitat by forestry activities, cultural and medicinal use and the presence
of possibly introduced fungal pathogens. An intensive exsitu conservation
project has been started in the Lowveld National Botanical Garden and it is
hoped that this species will be saved from extinction. |
Tree like,
Branched
Green leaves
Full Sun
Medium Water
Light Frost
Height: 3m |
Distribution
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Eco-types
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Habitat photo - Piggs Peak, Swaziland
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References & Acknowledgements
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Encephalartos Vol 40: Focus on Encephalartos heenanii - Johan
Hurter
- 1972. R.A. Dyer, Bothalia 10(4): 539-546
- Habitat Photo 1 -
Photographer Unknown
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Other Links
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