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Post by Melanie on Jan 8, 2007 16:27:04 GMT 1
Range A dwarf ebony, the identity of which has been confused with T. ebenus for the past 170 years. It probably occurred as a small shrub in arid areas of the north under the rain shadow of the central ridge. The genus is made up of just three species endemic to St Helena, two of which are extinct in the wild. Population The last sighting of it was recorded in 1771. www.iucnredlist.org/search/details.php/30561/summ |
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Post by Melanie on Jul 5, 2008 16:44:02 GMT 1
syn: Trochetia melanoxylon, Melhania melanoxylon, Dombeya melanoxylon
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Post by Melanie on Jul 5, 2008 16:47:32 GMT 1
Trochetiopsis melanoxylon (R.Brown ex Aiton f.) W. Marais St. Helena Dwarf Ebony St. Helena Blackwood T. melanoxylon was not distinguished from T. ebenus until 1995, both species being subsumed under the former name until then. Confusion between the two species remains in some of the literature. T. melanoxylon was a dwarf shrub growing at low altitudes in the arid rain shadow areas north of the central ridge. The bark of old wood is rather rough, and dark olive-black in colour. The foliage is alternate, long-petiolate and stipulate. The stipules are awl-shaped. The ovate leaves are 3-nerved, cordate at the base, with subentire margins. The are smooth above, and covered with a ferruginous stellate indumentum beneath. This indumentum is shared with the young shoots, petioles, peduncles, bracteoles and calyx. The flowers are large and campanulate, opening white and becoming pink or rosy as they age. They are borne on solitary, axillary peduncles, with one or two flowers borne on each peduncle. They are involucellate, the three bracteoles being ovate-lanceolate, and closely appressed to the calyx. There are 5 stamens, and 5 dark purple, club-shaped, staminodes. The fruit is an ovate, obtuse, capsule, with two or three seeds in each cell. It is much shorter than the persistent calyx. Due the confusion between T. melanoxylon and T. ebenus the status of T. melanoxylon is not wholly clear to me, but it would appear that T. melanoxylon is extinct, not having been recorded since 1771, and that plants in cultivation under this name are T. ebenus. www.malvaceae.info/Genera/Trochetiopsis/Trochetiopsis.html#melanoxylon |
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Post by Melanie on Jul 5, 2008 16:55:33 GMT 1
Added to this grim picture were the effects of habitat destruction. The impact of great numbers of goats on the native vegetation can hardly have been less than extremely deleterious. Man devastated the forest cover for fuel and timbers, and any regrowth was prevented by goats. Several plant species became extinct, the most notable of which was the ebony tree Melhania melanoxylon, which was entirely destroyed to provide fuel for burning lime. The great forests of St. Helena were wiped out by the beginning of the 19th century (Melliss, 1875). Added to this were the numerous intentional introductions of exotic plants that began under the Portuguese and increased under later British colonization. Today the only remaining native vegetation, dominated now by the tree fern Dicksonia arborescens, is confined to a small area on the high central ridge of the island, and this area is fast being encroached upon by New Zealand flax (Phormium tenax), gorse (Ulex), and other introduced plants. Probably as a result of habitat destruction the endemic land snails of St. Helena fared poorly, and, as with the birds, a greater proportion of the species are known only from fossil and subfossil remains (Wollaston, 1878). Paleornithology of St. Helena Island, South Atlantic Ocean si-pddr.si.edu/dspace/bitstream/10088/1952/2/SCtP-0023-Lo_res.pdf |
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Post by Melanie on Jul 5, 2008 17:00:00 GMT 1
St Helena is divided into three vegetation zones: Op the coast zone, extending inland for 1 m. to 12 m., formerly clothed with a luxuriant vegetation, but now " dry, barren, soilless, lichencoated, and rocky," with little save prickly pears, wire grass and Mesembryanthemum; (2) the middle zone (400-1800 ft.), extending about three-quarters of a mile inland, with shallower valleys and grassier slopes - the English broom and gorse, brambles, willows, poplars, Scotch pines, &c., being the prevailing forms; and (3) the central zone, about 3 in. long and 2 m. wide, the home, for the most part, of the indigenous flora. According to W. B. Hemsley (in his report on the botany of the Atlantic Islands),' the certainly indigenous species of plants are 65, the probably indigenous 24 and the doubtfully indigenous 5; total 94. Of the 38 flowering plants 20 are shrubs or small trees. With the exception of Scirpus nodosus. all the 38 are peculiar to the island; and the same is true of 12 of the 27 vascular cryptogams (a remarkable proportion). Since the flora began to be studied, two species - Melhania melanoxylon and Acalypha rubra - are known to have become extinct; and at least two others have probably shared the same fate - Heliotropium pennifolium and Demazeria obliterata. Melhania melanoxylon, or " native ebony," once abounded in parts of the island now barren; but the young trees were allowed to be destroyed by the goats of the early settlers, and it is now extinct. Its beautiful congener Melhania erythroxylon (" redwood ") was still tolerably plentiful in 1810, but is now reduced to a few specimens. Very rare, too, has become Pelargonium cotyledonis, called " Old Father Live-for-ever," from its retaining vitality for months without soil or water. Commidendron robustum (" gumwood "), a tree about 20 ft. high, once the most abundant in the island, was represented in 1868 by about 1300 or 1400 examples; and Commidendron rugosum (" scrubwood ") is confined to somewhat limited regions. Both these plants are characterized by a daisyor aster-like blossom. The affinities of the indigenous flora of St Helena were described by Sir Joseph Hooker as African, but George Bentham points out that the Compositae shows, at least in its older forms, a connexion rather with South America. The exotic flora introduced from all parts of the world gives the island almost the aspect of a botanic garden. The oak, thoroughly naturalized, grows alongside of the bamboo and banana. Among other trees and plants are the common English gorse; Rubus pinnatus, probably introduced from Africa about 1 775; Hypochaeris radicata, which above 1500 ft. forms the dandelion of the country; the beautiful but aggressive Buddleia Madagascariensis; Physalis peruviana; the common castor-oil plant; and the pride of India. The peepul is the principal shade tree in Jamestown, and in Jamestown valley the date-palm grows freely. Orange and lemon trees, once common, are now scarce. www.1911encyclopedia.org/Claude_Louis,_comte_de_Saint-Germain |
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Post by Melanie on Jul 5, 2008 17:01:48 GMT 1
1 Partridges: according to J. C. Melliss (Ibis, 1870, p. 170) the Indian Chukar, Alectoris gracca chukar (J. E. Gray) had been introduced into St Helena and had become abundant as early as 1588, when Cavendish mentioned it in his Travels. Sclater (Syst. Av. Aethiop. 1924) also records it as an introduced species. The doves may have been the European Rock Dove, Columba livia Gm., also recorded in St Helena by Melliss as both a wild and domestic species, probably introduced. 2 Melhania melanoxylon Ait. 3 Melliss saw the last living Ebony trees in 1850, and in 1875 ornaments made of its wood were fetching good prices. He remarks, ‘That this tree once formed a considerable portion of the vegetation clothing the Island in those parts that are now quite barren, is strongly evidenced by the many references to it in the local records’. St. Helena (London 1875), p. 245. Ebonywood was used to burn lime with. Its bark and that of the related redwood were both used in tanning leather. Melliss quotes an Ms record of 1709 that their destruction was hastened ‘by the Tanners, that for lasieness never took the paines to barke the whole trees but only the bodys, leaving the best of the bark on the branches, by which means has [sic] destroyed all those trees, at least three for one …’ .—ibid., pp. 226–7 n. www.nzetc.org/tm/scholarly/tei-Bea02Bank-t1-body-d5-d8.html |
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Post by Melanie on Jul 5, 2008 17:13:10 GMT 1
Melhania melanoxylon, Ait. Melhania melanoxylon, Ait., Hort. Kew, ed. 2, iv. p. 146 ; Melliss, St Hel., p. 245, t. 29. Pentapetes erythroxylon, Bot. Mag., t. 1000, non Ait., Hort. Kew, ed. 1, ii. p. 438. Dombeya erythroxylon, Andr., Bot. Rep., t. 389. Dombeya melanoxylon, Roxb. in Beatson's St Helena Tracts, p. 307. Trochetia melanoxylon, Benth. et Hook, f., Gen. Plant., i. p. 222. Alcea arbor populnea, &c, Pluk., Almag. Mant., p. 6, et Amalth., t. 333, fig. 3. St Helena.—Endemic. Barren rocks near the sea, and not far from Sandy Bay— Roxburgh; at Man and Horse and High Hill—Burchell. " Native Ebony." This tree appears to be quite extinct in the island, and probably no longer exists under cultivation. In Burchell's time it grew in the localities named above, and, according to bis notes in Kew library, in a few others. " This plant I believe to be now extinct. It formerly grew on tbe outer portions of tbe island near the coast, at altitudes of 1000 to 2000 feet, where tbe weatberbeaten stems are still found deeply embedded in tbe surface soil. Tbe last plant I saw was a small one growing in the garden at Oakbank about twenty-five years ago, but it is not tbere now, and I have in vain searcbed tbe wbole island over for another. The leaves were dark-green, and the flowers white ; tbe wood is very bard, heavy, black in colour, and extremely brittle. It is still collected and turned into ornaments, which are mucb prized on account of its rarity. That this tree once formed a considerable portion of tbe vegetation, clothing the island on those parts tbat are now quite barren, is strongly evidenced by tbe many references to it in the local records."—Melliss. Roxburgh mentions that he saw tbe ebony in two gardens only, where it had in many years grown to tbe height of only two or three feet, with many longer branches spreading flat on tbe ground, well decorated with abundance of foliage and large handsome flowers. Source: Report on the scientific results of the voyage of H.M.S. Challenger during the years 1873-76 : under the command of Captain George S. Nares, R.N., F.R.S. and Captain Frank Turle Thomson, R.N. (1885) . www.archive.org/details/reportonscientif188501grea |
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Post by Melanie on Jul 5, 2008 17:59:17 GMT 1
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Post by anotherspecialist on Jul 5, 2008 20:16:26 GMT 1
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Post by anotherspecialist on Jul 6, 2008 10:40:51 GMT 1
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Post by anotherspecialist on Jul 6, 2008 10:45:27 GMT 1
  Repository Royal Botanic Gardens, Kew (K) Collection Type specimens Collector Forsyth, No# unknown Country Saint Helena (St Helena) Identifications Trochetiopsis ebenus Q.C.B.Cronk [family STERCULIACEAE] (stored under name); Verified by Brodie, S. M., 05-1997 Dombeya melanoxylon Roxb. [family STERCULIACEAE]; Trochetiopsis melanoxylon (R.Brown ex Aiton f.)W.Marais [family STERCULIACEAE]; Notes Herbarium of the late W. J. BURCHELL, D. C. L. Presented by Miss Burchell, May 1865 Ex herb. A. Blambert Repository Royal Botanic Gardens, Kew, London, England, UK, K000241239 Data last modified 07-06-2005 www.aluka.org |
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Post by Surroundx on Apr 26, 2015 9:38:31 GMT 1
Cronk, Q. C. B. (1986). The decline of the St Helena ebony Trochetiopsis melanoxylon. Biological Conservation 35(2): 159-172. [ Abstract] |
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