A precarious hold on life

Although the list of extinct succulents is, mercifully, still short, there are many instances where life hangs by a thread. Saphesia flaccida (page 135) is a distinctive member of the Mesembryanthema-ceae with a long, thick caudex and unique fruit structure. It was known in cultivation in 1804 and given its scientific name by Baron Jacquin from material studied in his famous garden at Schoen-brunn near Vienna. For a period of 130 years all that was known of it was Jacquin's very fine published colour plate1, and one specimen in the herbarium at Kew. Then in 1934 a few plants were recognized growing in the wild at Kalabas Kraal near Cape Town. By 1950 H.Herre, curator of the Stellenbosch Botanic Garden, could find only one survivor2 in that locale and the whole area is rapidly disappearing beneath the plough. Xerosicyos pubescens is a curious member of the cucumber family, very different from the other known members of its genus. It was known from a single male plant, now dead, in Tananarive Botanic Garden in Madagascar; its habitat, though not exactly located, is thought to have been in that part of the island now completely cleared of wild flora.

Some succulents are more common in cultivation than in the wild. One such is Aloe variegata. the 'Partridge Aloe', so familiar on cottage windowsills in the Northern Hemisphere. The reason for its decline in its native South Africa is over-collecting to meet the demand for quick sales. Field collectors are much blamed for the near-extermination of rare species, but they are only one of many adverse

Right (7.1 J: The Hester Malan Wild Flower Reserve near Springbok in South Africa. a line unspoiled area of mountains and valleys covering 12.000 acres To the rich native flora are added other plants from N

factors—a serious one. but not the worst. Even the most ruthless habitat-stripper usually leaves behind a few specimens that are too large, too old. misshapen or inaccessible, whereas grazing animals, bulldozers and weedkillers make no such distinction.

Dwarf, free-flowering succulents have suffered more than most because their rising popularity in America, Europe and Japan has increased the drain on habitats. In 1968 1 visited the type locality of Mammillaria louisae. a most alluring miniature, near Socorro in Lower California and spent an hour searching the ground with two other lynx-eyed botanists. Although this species was once abundant in that area, we found less than a dozen, and a second visit in 1974 confirmed the scarcity. What is so frustrating is that M.louisae is one of the easiest cacti to raise from seed, and two-

year-old plants flowerand set seed readily (7.3), so there is absolutely no justification for plundering wild populations.

TTie introduction of the ostrich to South Africa and the goat to almost anywhere has had a profound effect on natural vegetation. The recording angel's list of crimes committed against plant lovers by goats must run to many volumes. The unique Talinum guadalupense (15.4) has been eaten off Guadalupe Island, 400km (250miles) south of San Diego, and survives only on rocky islets that no goats have yet reached. Goats are not choosy about their diet, and few plants are spared. Many of the more choice succulents owe their survival to the shelter of small shrubs, and once theseare removed nothing can survive, and a true desert takes over.

A long list could be made of the factors responsible for the retreat of natural vegetation: expanding cities, agriculture, mining, the building of roads and airstrips, weedkiller spraying, polluted air. overgrazing, overcollectingand soon. We cannot demand a halt to these, any more than we can expect a "Keep out" notice on a nature reserve to deter nomadic tribes in East Africa whose survival depends upon finding new grazing grounds. It is a lot easier to catalogue the causes than to supply remedies.

Is there a remedy? Legislation to control collecting is one obvious step to take, and it has been introduced in Africa and North America. But it has its drawbacks. One is that genuine nature lovers are made to suffer along with the commercial grabbers and grubbers. Botanists and nurserymen become involved in endless paperwork to comply with the law, and the demise of

rare plants may even be hastened by placing restrictions on their free circulation in cultivation. Meanwhile, despite the laws, digging goes on, because the areas involved are too vast for adequate policing.

Nature reserves provide an ideal answer: conserve slices of the habitat

known to be rich in endangered species. But whereas game parks for animals are many and well-publicized, the equivalents for plants are much fewer, although some of the game parks incidentally preserve plants of the area. The Hester Malan Wild Flower Reserve near Springbok in

(12.000acres)of splendid, rugged, largely unspoiled country rich in endemics, and more are added from time to time to conserve the whole of the flora of Namaqualand. We need many more flow-

¿ssszszs.

s: Which plants are most endangered? And where? The areas concerned are vast, and most of the sampling is limited to roadsides. This over the known habitats in an aeroplane and noted the long gaps between where one track ends and the next begins. The going is rough 01 stretch toward th unsurveyed.

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