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Encephalartos horridus
(Jacq.) Lehm.
Eastern Cape Blue Cycad
Zamiaceae
Encephalartos horridus is a species of cycad in the family Zamiaceae. It is restricted to a small area in Eastern Cape province, South Africa. It is often grown as an ornamental for its attractive appearance.
Description
Encephalartos horridus is a short plant usually with underground stems, often with offsets at the base. Leaves are rigid, 0.5 to 1 m long and 10 to 15 cm wide, pinnate, on a 12 to 15 cm long, 1.2 cm diameter stalk. They have numerous leaflets, 10 to 13 cm long and 2.5 to 3.5 cm wide, reduced to prickles at the base of the leaf. Leaflets have two to three sharply pointed lobes that are often strongly twisted and interlocking with neighboring leaflets. They are strikingly silver-blue when young, aging to a dull green. Male (pollen) cones are sometimes found in pairs. They are approximately cylindrical, 20 to 40 cm tall and 6 to 12 cm wide, bluish green at the base and covered with brownish hair. The stalk is 4.0 to 4.5 cm long, dull green, brown-hairy. Sporophylls (cone “scales”) are distinctly faceted, 3.5 to 4 cm long, with the main facet being 15 to 18 mm high and 35 to 40 mm wide, and a beak that extends out 1 cm. Seeds are borne on separate plants. Female cones hold seeds, and are solitary. They are bluish green with brownish hair, ovoid, about 20 to 40 cm long, 15 to 20 cm wide, on a hidden stalk. Sporophylls are distinctly faceted, with the main facet being 3 to 3.5 cm high, 4 to 4.5 cm wide, projecting a few cm out, with a rough surface and distinct edges. Seeds are about 2.5 to 2.8 cm long, 1.5 to 1.8 cm wide, with an outer layer (sarcotesta) that is reddish (Whitelock 2003).
Uses
Note: Please see the disclaimer regarding any information about medical or edible uses.
Encephalartos horridus is often grown as an ornamental because of its attractive, unusually blue-colored leaves (Whitelock 2003). It is hardy in USDA zones 10 to 12, and prefers full sun, rich, well-draining soil, and medium moisture (MBG).
Distribution
Encephalartos horridus is often grown as an ornamental because of its attractive, unusually blue-colored leaves (Whitelock 2003). It is hardy in USDA zones 10 to 12, and prefers full sun, rich, well-draining soil, and medium moisture (MBG).
Status
Encephalartos horridus is listed on the IUCN Red List as "Endangered". The species has undergone significant population decline, and is threatened by over-collecting, as well as habitat destruction for development. It is listed in Appendix I of CITES, an international treaty regulating the trade of endangered species (Donaldson 2010).
References
Donaldson, J. S. 2010. Encephalartos horridus. The IUCN Red List of Threatened Species. https://dx.doi.org/10.2305/IUCN.UK.2010-3.RLTS.T41905A10587904.en.
MBG (Missouri Botanical Garden), Encephalartos horridus. Plant Finder. [accessed 2019 Feb 12]. http://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?taxonid=279662.
Whitelock, L. M. 2003. The Cycads. Portland: Timber Press.
MBG (Missouri Botanical Garden), Encephalartos horridus. Plant Finder. [accessed 2019 Feb 12]. http://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?taxonid=279662.
Whitelock, L. M. 2003. The Cycads. Portland: Timber Press.
Description
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