The Cycad Page

Cycas revoluta  Thunburg 1782 (King Sago Palm)
Name: leaflets curl under along their edge = revolute
 
This is probably the most widely-cultivated Cycad. Its attractive feathery foliage adds an exotic touch to any conservatory. A plant should not be moved while it's leaves are unfurling as they will become distorted, and being long-lasting, will spoil the plant's very symmetrical appearance for some years. Even a small plant develops a conical caudex which, with age slowly elongates into an unbranching trunk, and may offset at it's base to form a clump. A several centuries old plant may develop a 6 ft trunk.
 
Cycas revoluta is native to the southern Japan islands of Kyushu and Ryukyu, growing further North than any other species of Cycad. It is a very hardy plant, tolerating drought, and light frosts and is almost hardy in South-East England through an average Winter. Several specimens survive planted in sunny corners outside the Temperate House in Kew Gardens.
 
All parts of the Sago Palm Cycad are extremely poisonous to animals if ingested. The seeds contain the highest level of the toxin Cycasin and other harmful metabolites.

Cycas siamensis  Miquel 1863
Name: Siam is an old name for Thailand 
This Cycad produces flat leaves whose colour (silvery-white, yellow, orange, brown) depends on the colour of hairs on the leaves.
 
Native to Thailand and Vietnam. All parts of the plant are poisonous if ingested

Cycas thouarsii  R. Brown ex Gaudichaud 1829 (Madagascar Sago)
Named for: French botanist Louis-Marie Aubert du Petit-Thouars (1758-1831) 
This Cycad has a stout trunk over 30ft tall topped with a crown of up to 40 feathery pinnate leaves. Offsets may be produced along the length of the trunk.
Native to coastal Kenya, Tanzania and Mozambique, Madagascar, Comoros Islands and introduced into the Seychelles. This Cycad probably originated over 140 million years ago and may be the most ancient living species. It is relatively fast-growing, tolerating light frosts.

Bowenia serrulata  Chamberlain 1912 (Byfield Fern)  Syn. B. spectabilis Bull 1878
Name: Latin serrulatus = serrated or toothed, referring to the leaf margins. 
The 10 - 12 in globular subterranean stem produces up to 20 branching bipinnate leaves 4 - 5 ft tall, whose leaflets with finely-serrated edges. The stem has a large tap root.
 
Native to warm, dry Eucalyptus forests of Eastern Queensland where it grows as an understorey plant.

Bowenia spectabilis  Hooker ex Hooker fils. 1863 (Zamia Fern)
Name: Latin spectabilis = remarkable, showy 
The type species for the genus, native to subtropical moist forests in North-Eastern Queensland. The underground stem produces up to seven 4 - 5 ft branching, bipinnate leaves whose leaflets have smooth margins.

Stangeria eriopus  Baillon 1892 (Natal Grass Cycad)
Name: Greek erio = woolly + pus = footed, referring to the woolly petiole base. 
The thick stem is subterranean, with a tap-root and corralloid roots near the surface housing nitrogen-fixing cyanobacteria. The stem is crowned with distinctive pinnately-veined, fern-like leaves. Indeed this Cycad was originally described as a fern (Lomaria eriopus Kunze 1839) and the mistake only realised when seed cones were observed. This variable Cycad has a forest form (above) bearing soft, thin, wide 6ft leaves and a more compact form (below) from open grassland with smaller, thicker 1ft long stiff leaves.
 
Stangeria eriopus matures relatively quickly for a Cycad, usually after 5 - 7 years, from which time male and female stalked cones are produced on separate plants. The cones produce a perfume to attract beetle pollinators.
 
Native to coastal Eastern South Africa and Southern Mozambique, although not within range of salt spray. Stangeria eriopus, especially the root, is a traditional medicine as a purgative and for treating headaches

Ceratozamia hildae  G.P.Landry & M.C.Wilson 1979 (Bamboo Cycad)
Named for: Hilda Guerra Walker daughter of Luciano Guerra who first collected this Cycad in 1959. 
This small Ceratozamia has 3 - 4 ft leaves whose leaflets cluster in groups of two or three pairs either side of the midrib, looking like a string of bow ties. The subterranean trunk offsets to form a clump.
 
Native to deciduous oak cloud forests on limestone soils in the Mexican states of Querétaro and San Luis Potosí, but almost extinct in its habitat. This shade-loving Cycad is relatively fast growing and popular with collectors. Growing naturally at elevations up to 4500 ft, it is said to be frost tolerant.

Ceratozamia kuesteriana  Regel 1857 (Von Kuester's horncone)  Syn. C. angustifolia
Named for: Baron Karl von Küester (1820 - 1893), Administrator & Head of St. Petersburg's Botanical Garden. 
This small Ceratozamia has a globose mostly subterranean trunk producing 3 - 4 ft dark-green leaves with smooth petioles and many narrow drooping leaflets. New leaves are coloured bronze.
 
Native to pine & oak cloud forests at elevations of up to 6000 ft in a limited range of the Sierra Madre Oriental Mountains of the Mexican state of Tamaulipas.

Ceratozamia mexicana  Brongniart 1846 (Mexican Horncone)
Ceratozamia mexicana is the type species of the genus. It has a large prostrate stem, offsetting at the base to make a large clump. New leaves are hairy and may be bronze to light green in colour. The petioles are spiny as are the large cones.
 
Native to wet and dry forests of mountains in the Mexican state of Veracruz.

Ceratozamia miqueliana  Wendland 1854 (Mexican Horncone)
This small Cycad has a mainly subterranean or prostrate stem which produces 6ft spreading pale glaucous green pinnate leaves with broad, pointed leaflets.
 
Native to the Mexican states of Chiapas, Tabasco (extinct) and Veracruz, where it grows at moderate altitudes in cool, moist rainforest. Habitat destruction and collecting threaten the survival of this species. This is not a frost-tolerant Cycad although the subterranean stems may survive light frost.

Ceratozamia robusta  Miquel 1847 (Costilla De León)
Syn. Ceratozamia mexicana var. robusta, Zamia macrophylla
 
This is the largest Ceratozamia species. It develops a 6ft trunk crowned with dark-green pinnate leaves up to 8 ft long, with up to 200 narrow leaflets and a spiny petiole.
 
Native to the Mexican states of Chiapas, Oaxaca and Veracruz, Belize and Guatemala where it grows as an understorey plant in warm, humid forests.

Dioon edule  Lindley 1843 (Chestnut Dioon, Palma de la Virgen)
Name: refers to former use of the seeds to make flour for tortillas. 
Dioon edule has a short trunk up to 10ft tall, bearing a crown of stiff, upright, bipinnate blue-grey leaves with a feathery appearance. Leaflets on young plants have spines but these are absent in mature plants. However, the leaflets still have sharp tips. Offsets may be produced at the base of the trunk.
 
A drought-resistant plant native to arid parts of Eastern Mexico, Honduras and Nicaragua. This is a beautiful plant for landscaping in suitable climates and tolerates light frosts but probably not cold-wet winters. Despite former use as a food plant, all parts including the seeds are poisonous.

Dioon spinulosum  Dyer 1843 (Giant Dioon, Gum Palm)
This is one of the tallest Cycads in the world, potentially reaching heights of 50ft. The pinnate leaves have 140-240 leaflets which have small marginal thorns and are tapered to a sharp point. The cones are the largest of any known plant.
 
Native to the states of Veracruz and Oaxaca Mexico where it grows in tropical rainforest on limestone soils. This species is not hardy but will tolerate occasional light frosts.

Encephalartos altensteinii  Lehmann 1834 (Eastern Cape Giant Cycad, Bread Tree )
Named for: Baron von Stein zum Altenstein, Prussian statesman. 
This large impressive Cycad has a single erect trunk up to 15ft tall, often suckering at the base to form a clump with age. The pinnate 10ft long, deep green glossy leaves are long-lived, but a new flush of leaves is produced in the Spring. The broad, well-spaced leaflets have 1-3 prickles on their margin, but basal leaflets do not merge into spines leaving a short length of bare petiole. The midrib of the leaf is straight, not twisted.There is no wooly fibre in the crown around new leaves. Yellowish male and female cones are produced at the stem tips of separate plants.
 
Encephalartos altensteinii is native to the South-Eastern Cape of South Africa, a Summer rainfall area and a guide to watering the plant. It is commonly grown in tropical gardens, but is very slow-growing. It will not stand more than the lightest frost.
 
 
Left: This huge multi-stemmed E. altensteinii in the Kew Palm House arrived at Kew in 1775 and is claimed as the oldest pot plant in the world, although by no means the oldest specimen in cultivation. A specimen of E. altensteinii in Lednice Greenhouse, Czech Republic is 400 - 500 years old.

Encephalartos arenarius  Dyer 1955 (Alexandria Cycad)
Name: Latin arenarius = growing in sandy places 
Encephalartos arenarius has a stout 4 ft stem that may be either subterranean in leaf litter or prostrate. The plant clumps up by offsetting at the base. The 4 ft pinnate leaves are recurved at their ends and consists of many broad, hard leaflets with prickly lobes. Two forms of E. arenarius are known with either dull green or bluish leaves.
 
Native to coastal sandy dune forest around Alexandria in the Eastern Cape of South Africa, although much habitat has been lost from conversion to pastures.

Encephalartos cupidus  Dyer 1971
Name: Latin cupidus = bristly 
The mainly subterranean main stem produces 3ft pinnate blue-green leaves. The leaflets form a V-shape on the mid-rib and are reduced to vestigal prickles on the petiole. They have 4 - 6 spines on each margin. The cones are greenish.
 
Native to the Eastern Transvaal Drakensberg escarpment, occurring as small populations. Plants may clump up by suckering.

Encephalartos ferox  Bertolini 1851 Syn. E. kosiensis (Zululand or Tongaland Cycad, Tongaland Broodboom)
Name: Latin ferox = ferocious, referring to the rigid, spiny leaflets. 
This medium sized Cycad has a stout 3 - 4 ft long trunk which can be mostly subterranean, pulled down by contractile roots. The pinnate leaves have hard ovate blue-green leaflets with spine-tipped lobes, forming a shallow V-shape along the mid-rib.
 
Left: The male and female cones on separate plants are a dark salmon-pink. The male cone is an elongated cylinder narrowing at each end and the female cone is egg shaped.
 
Encephalartos ferox is native to coastal Mozambique and Natal where it grows on sand dunes and evergreen forests. The starchy pith has been used to make a flour after fermentation to remove toxins.

Encephalartos horridus  Lehmann 1834 (Eastern Cape Blue Cycad)
Name: Latin horridus = bristly 
This low-growing Cycad has the majority of its large 3ft long stem underground, although more may be exposed when growing in rocky terrain. Two forms are recognised: a robust form and a dwarf form with shorter stems and smaller leaves. The freely-branching stem is crowned with 4 - 8 stems of distinctive blue-grey leaves with stiff, spiny leaflets. After becoming mature, each crown of the plant produces a single brown or dark red cone covered in fine hair.
 
Female cones are egg-shaped and male cones cylindrical with narrow ends. Female cones produce toxic seeds surrounded by a fleshy skin which is eaten by birds and monkeys, while discarding and dispersing the more toxic seeds.
 
Native to the Eastern Cape of South Africa around Port Elizabeth and Uitenhage, growing on acidic soils. Because of its unique appearance, natural populations have been depleted by over-collection. Not cold-hardy but may tolerate brief, light frosts.

Encephalartos lanatus  Stapf & Burtt Davy 1926 (Woolly Cycad, Olifants River Cycad)
Name: Latin lanatus = woolly 
This medium-sized Cycad has a globular caudex becoming a thick 4ft tall stem with great age. The stem bears many leaf scars and is crowned with blue-grey 3ft leaves which are covered in silver hairs when young. The leaflets for a V-shape along the mid-rib and the leaves tend to recurve. The cones are also covered with persistent silvery hairs.
 
Native to limited locations in the Transvaal at altitudes of 4000 - 5000 ft. This slow-growing Cycad is frost hardy and adapted to both drought and bush fires but dislikes too much water.

Encephalartos lehmannii  Lehmann 1834 (Karoo Cycad)
Named for: Professor J.G.C. Lehmann of Hamburg who erected the genus. 
This Cycad has a stout trunk up to 6ft tall, crowned with a whorl of beautiful feathery blue leaves 3 - 4 ft long. The stems clump up from the base.
 
Native to the Eastern Cape Province of South Africa. One of the most drought resistant Cycads and tolerates a degree of frost.

Encephalartos longifolius  Lehmann 1834 (Thunberg's Cycad, Suurberg Cycad, Bread Palm, Suurbergbroodboom)
Name: Latin longis = long + folius = leaf 
The thick trunk up to 15ft tall, produces a crown of glossy, dark-green leaves curving outwards towards their ends. The lanceolate leaflets are arranged on the mid-rib in a distinctive V-shape. Their lower margin may have a small number of teeth. This species clumps up by offsetting from the base. The large olive-green female cones are the heaviest of any Cycad. Male cones are brownish. The seeds are very toxic.
 
Native to the Eastern Cape. The starchy pith was fermented to remove toxins and used to make a flour. One of the first Cycads to be discovered by the Swedish botanist Carl Peter Thunberg and Francis Masson in 1772.

Encephalartos natalensis  Dyer & Verdoorn 1951 (Natal Giant Cycad, Natalbroodboom)

 
The stout trunk can grow 20ft tall and is crowned with 10 ft long pinnate leaves with many well-spaced bright-green ovate leaflets, usually but not always without marginal prickles. Basal leaflets are reduced to spines along the petiole. New leaves and cones are covered in yellowish hairs. The cones are yellow and ovoid. Female cones contain toxic red seeds.
 
Native to the Eastern Cape Province and KwaZulu-Natal. The starchy pith of the trunk was processed into a flour. This Cycad is closely related to E. altensteinii.

Encephalartos paucidentatus  Stapf & Burtt Davy 1926 (Barberton Cycad)
Name: Latin paucus = few + dentatus = toothed 
The stout upright or procumbent 20ft trunk produces a crown of glossy green leaves which are covered in brown hairs when young. Individual leaflets are relatively large and lanceolate with few marginal teeth. The cylindrical golden cones are probably pollinated by snout beetles.
Native to mountains of Eastern Mpumalanga, RSA, near Barberton and mountains of North-Western Swaziland.

Above: Encephalartos villosus  Lemaire 1867 (Poor Man's Cycad)
Name: Latin villosus = hairy 
This dwarf species has an almost entirely subterranean stem, it's crown supporting spreading 10ft pinnate glossy dark green leaves. The leaves are covered with white hairs when freshly unfurled.
 
Male plants can produce up to 5 yellowish elongated cylindrical cones with an unpleasant odour when mature. The odour attracts a specific pollinator weevil Antliarhinus zamiae. Female plants have deep yellow ovate cones, developing fleshy dark red seeds that are eaten and distributed by birds.
 
Encephalartos villosus is native to the Eastern Cape of South Africa where it is common, although somewhat depleted by collection and clearance for agriculture. This shade-loving plant typically grows as an understorey plant in forests experiencing Summer rainfall. Old speciments form multi-headed clumps. It is commonly cultivated as a dwarf ornamental plant for landscaping and conservatories.

Encephalartos woodii  Sander 1908 (Wood's Cycad)
Named for: John Medley Wood, curator of the Durban Botanic gardens, discoverer of this species. 
This is a very rare plant, possibly originating as a hybrid. Only a single male plant was ever found, but has been propagated by cuttings of basal offsets so that there are many clones growing in botanic gardens. It is thought to be related to Encephalartos natalensis.
 
Native to Ngoya Forest of South Africa.

Lepidozamia hopei  Regel 1876 (Hope's Cycad)
Named for: Louis Hope (1817-1894) sugar cane planter, pioneer of the Queensland sugar industry. 
This may be the tallest species of Cyad, with the potential to grow 60ft high. The bipinnate 10 ft long leaves have over 150 lanceolate leaflets. Dead leaves are persistent. The 2.5 ft female cones produce bright red oval seeds, which although very poisonous were processed by aborigines into food.
 
Native to North-Eastern Queensland.

Lepidozamia peroffskyana  Regel 1857
Named for: Count Peroffsky, Russian benefactor of the St Petersburg Botanic Garden. 
This species makes a large tree although smaller than L. hopei.
Native to the North coast of New South Wales and South-Eastern Queensland.

Macrozamia communis  L.A.S.Johnson, 1959 (Burrawang)
Named for: habit of growing in large, dense groups 
The caudex is mostly subterranean but can extend above ground as a short trunk in old plants or where the substrate is impenetrable.
 
Native to the open forests along the Eastern coast of New South Wales, extending inland to the slopes of the Great Dividing Range. The common name 'Burrawang' really belongs to this plant although it is often applied to other species of Macrozamia. The toxic yellow to red seeds were processed into flour by the Aborigines.

Macrozamia miquelii  de Candolle 1868
  Syn. Macrozamia miquelii Mueller 1862
Named for: F.A.W. Miquel, Dutch botanist and physician 
The caudex is mostly subterranean but can extend 2 - 3 ft above ground in old plants.
 
Native to coastal Southern Queensland and Northern New South Wales.

Macrozamia moorei  von Mueller 1881 (Moore's Cycad, Bottle Tree)
Named for: Charles Moore (1820-1905), director of the Royal Botanic Gardens, Sydney. 
Macrozamia moorei is the tallest Macrozamia with a massive 3ft diameter trunk up to 20 ft tall and covered with persistent leaf bases. The arching pinnate leaves up to 8ft long have numerous narrow leaflets arranged in a V-shape along the midrib. The lower leaflets degenerate into spines along the short petioles. Male and female cones are on separate plants. The barrel-shaped female cones contain many large scarlet seeds, which are extremely poisonous. However, Aboriginals made flour from the seeds after lengthy soaking in water to remove the toxins.
 
Native to central Queensland. This very slow-growing Cycad is propagated as a conservatory plant or for landscaping in Mediterranean climates.

Microcycas calocoma  De Candolle 1868 (Cork Palm)
 
This Cycad develops a stout 30ft trunk topped with feathery, pinnate dark-green leaves up to 4ft long supported on spineless petioles. The leaflets droop down from the mid-rib. Distal leaflets are of a similar size to those in the middle of the leaf, conferring a characteristic truncated appearance. The cones are cylindrical, yellowish-brown and hairy with two apical projections on each sporophyll. The 2 in long eliptical seeds are reddish.
 
Native to the forested lower slopes of mountains in Western Cuba but endangered through land clearance so the total population may consist of as few as 600 plants. The roots are traditionally used to make rat poison.

Zamia furfuracea  Linnaeus fils. 1789 (Cardboard Palm) Syn. Z. maritima
Name: Latin furfuracea = "mealy, scurfy" 
The short, partly subterranean trunk is crowned with stiff pinnate leaves composed of up to twelve stiff, pubescent leaflets, sometimes with toothed tips.
 
Mature plants produce redish-brown cones in the centre of the plant. Pollination is by the belid weevil Rhopalotria mollis. Female cones produce fleshy, crimson-coloured seeds which are very poisonous if ingested.

Native to the Mexican state of Veracruz, growing in sand dunes where it tolerates some salt spray. A slow growing plant when young but tolerant of cultural conditions. May tolerate very light frosts, with regrowth of damaged leaves. This species is widely grown as a houseplant.
 
All parts of the plant are poisonous if ingested, causing liver and kidney failure and paralysis. There is no antidote.

Above: Zamia integrifolia  Linnaeus fils. 1789 (Coontie, Florida arrowroot, wild sago) Syn. Z. floridana, Z. pumila
Name: Latin integrifolia = entire + folium = leaf, refers to leaf margins without teeth (not quite correct). Seminole Native American  conti hateka = "white flour root" -> Coontie (or koonti). 
Zamia integrifolia has a short 10 in trunk, often mostly subterranean, and a substantial tuberous root. The stem is crowned with pinnate leaves formed from up to thirty pairs of lanceolate leaflets which may have indistinctly toothed tips. Petioles are often prickly and young leaves are covered in reddish-brown hairs. In a temperate climate the leaves can be deciduous during cold periods, making this species relatively hardy to light frosts. Separate plants produce clusters of cylindrical male cones and ovoid female cones.
 
Zamia integrifolia is the only Cycad native to the South-Eastern USA, growing on limestone or sandy soils as far North as Florida and Georgia. Also native to the Bahamas, Cuba, Grand Cayman, Hispaniola, and Puerto Rico although populations have been depleted in parts of the original distribution. Some authors split this variable species into others e.g. Zamia floridana, Z. augustifolia, Z. floridana, Z. pumila, Z. silvicola, and Z. umbrosa.
 
All parts are poisonous if ingested, especially the fleshy red seeds. However, the common name refers to use of the Coontie, with considerable processing, to make an edible starch. Zamia integrifolia and related Zamias are the sole food plants for caterpillars of the endangered butterfly Eumaeus atala.

Zamia loddigesii  Miquel 1843  Syn. Zamia cycadifolia Dyer 1884
Named for: Conrad Loddiges, English nurseryman. 
This Cycad has a small, usually subterranean caudex bearing up to 6 pinnate leaves supported on spiny petioles. The stiff leaflets are lanceolate with slightly toothed margins.
 
Native to sandy soils at modest elevations in Eastern Mexico and Guatemala, where it is common but threatened by habitat loss. A drought tolerant plant suitable for xerophytic landscaping.

Zamia muricata  Willdenow 1806 Syn. Z. verschaffeltii, Z. monticola
 
The short stem, branching with age, produces a crown of up to six upright leaves which increase in length and number of leaflets as the plant matures. This is a relatively fast-growing plant, becoming mature with production of cones after 5 - 6 years.
 
Native to low-level rainforests of Colombia and Venezuela where it grows as an understorey plant in wet clay soils.

Zamia neurophyllidia  Stevenson 1993
Name: refers to the nerve-like network of grooves in the leaves 
This small plant has a short trunk producing up to ten pinnate leaves with small prickles along their margins and prickles along the petiole. Very similar to Z. skinneri from which it was separated, but is smaller and with fewer chromosomes.
 
Native to low-altitude tropical rainforests of Costa Rica, Nicaragua and Panama. Needs moist but not soggy soil.

Zamia vasquuezii  Stevenson, Sabato, Moretti & De Luca 1995 (Chamalillo, Teocinte)
Named for: Mario Vazquez Torres, Mexican botanist who discovered this species. 
A small Cycad with a subterranean trunk producing a crown of 3 ft pinnate leaves with more than 12 pairs of leaflets with toothed margins and small spines on the petioles. Similar to the smaller Z. fischeri, from which it was segregated. Z. fischeri has fewer, smaller leaves with less than 12 pairs of leaflets.
 
Native to pine - oak forests in the Northern part of the Mexican state of Veracruz although severely depleted in its habitat.