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For the next several columns I’m going to change topics a bit, and rather than discuss various genera and species of succulent plants, I’ll be writing about some of the really strange places where some of these plants are found. Most people assume that cacti and succulents live in deserts, and when they think “desert,” they conjure up a vision of sand dunes, maybe with a camel wandering by, or bizarre rock formations out of the “Krazy Kat” comic strip of the early 20th century. In most cases, this is simply not the case. The average habitat in which cacti and succulents grow resembles the interior foothills of California , semi-arid, sparsely dotted here and there with trees, and marked by occasional outcrops of bare rock. Whether in Mexico, South Africa, Argentina or Madagascar, these rocky outcrops and ledges are the type of micro-habitat selected by many succulent plants. Others succulents take shelter on flats or gentle slopes, where they often grow on the edges of, or even beneath, brush and shrubs. These fairly dry, but not totally arid habitats, no matter where they are, tend to resemble each other, at least in a general way. When looking at a photograph of dry hills, from Namibia, Sonora or Utah, it’s impossible to quickly and incontrovertibly determine exactly what place you are looking at—it could be any of them.
In sharp contrast to these topographic generalities of semi-aridity, however, a picture of one of several areas that are home to some of the most interesting succulents and cacti would almost immediately reveal itself to anyone with a decent familiarity with these sorts of very strange places. Many of the regions could be considered true deserts, but with little if any resemblance to the clichéd image of such habitats. The one I’m going to be featuring in this month’s column is that portion of northwest South Africa called Namaqualand .
Beginning near the town of Vanrhynsdorp (about 150 miles north of Capetown), and extending south to north for about two hundred miles, to the Namibian border, Namaqualand more-or-less parallels the Atlantic coast and averages a little less than fifty miles in width. It consists of several environmentally distinct sections, of which the northernmost, the unique environment called the Richtersveld, deserves a column all its own. The others include areas called the Hard Veld and the Sand Veld, and the southern part of Namaqualand centered around the very strange land of the Knersvlakte.
The western coastal regions of South Africa remain green and pleasantly pastoral for several dozen miles as you drive north along the national highway, the N-7. After a while, though, the landscape starts looking drier, and an assortment of succulent plants will appear in any appropriately open or rocky stretch of soil. Although all this country is in the winter rainfall area, most of it receives enough moisture to support a good cover of vegetation, and most of the succulents that live here have not had to undergo extreme modifications in order to be able to survive. The outlying members of the more specialized groups that do live here are often unusually well behaved in cultivation, able to survive more water and less specialized soil conditions than their northern cousins. The countryside near towns such as Piketberg and Clanwilliam, though supporting interesting populations of succulent plants, looks fairly ordinary, not unlike coastal California . Near Vanrhynsdorp, however, all that changes.
The dominant feature in this southern stretch of Namaqualand is the Knersvlakte, a several hundred square miles landscape of flat plains and low hills, almost all of which is completely covered with chunks of white quartz. The pebbles lay on top of sandy, highly alkaline soil almost completely devoid of organic matter. Quartzfields are characteristic of South Africa , though they also exist in a few other places in the world, but the Namaqualand quartzfields must be the most spectacular. Because they lie near the coast, in what can be termed a fog-desert, these Namaqualand quartzfields receive no rain in summer, and only a little in winter. Consequently, their complement of plant-life has had to adapt both to very odd soil and very odd rainfall patterns as well.
The Knersvlakte is the remnant of an ancient river delta; several million years ago the Orange (or Gariep) River emptied into the Atlantic a couple of hundred miles father south than it does today, and because of some twist of geology, the ancient river left this mostly flat plain covered with quartz. I used the term “spectacular,” but the Knersvlakte isn’t spectacular the way the Grand Canyon , for example, is. It’s spectacular in its oddness instead. From a distance the quartzfields look like vacant lots covered with gravel and almost devoid of vegetation. In reality, they support a huge variety of plant life, thousands of different species, a great many of them endemics. Almost all these plants, however, are very small, many tucked in between the quartz pebbles. Many are well camouflaged; all the species in the genus Argyroderma, for example, are Knersvlakte endemics, members of the Mesembryanthemaceae (Ice Plant family), that look like sky-blue Easter eggs partly cut in half. Their blue color blends in well with the quartz pebbles, and only the giant aggregations of plants formed by some of the species give them away from a distance, turning whole patches of ground blue instead of white with thousands of succulent blue heads growing within a few square yards. Mesembs, large and small, make up a major portion of the plant population of the quartzfields, ranging from good sized clumping plants to tiny individual species, but as a rule, the denser the quartz cover, the more miniaturized its inhabitants, or if not truly miniature, than truly strange, such as the two mesembs genera, Monilaria and Dactylopsis (or Phyllobulus) that can form bizarre little groves of (respectively) paired upright leaves covered with shimmering papillae, or weird upright clusters that strongly resemble the fingers of rubber gloves. This is during the winter “rainy” season; during the summer drought, and paired uprights shrink into columns of dried-up beads, while the fingers turn into very dead-looking husk-like blobs. Other mesembs from the quartzfields look like clusters of half-inch tall, diminutive footballs made of magenta leather, rounded bits of green or red jelly, or tiny green stones flattened and flush with the soil. They share their territory with dwarfed tylecodons, members of the Crassula family, with small underground tubers, short, almost hidden stems and round or heart-shaped, third of an inch wide, almost spherical leaves, green or red and marked with dots and tiny bristles. Quantities of bulbs flourish on the fringes of the quartzfields, bulbines that grow as either thick rosettes of transparent leaves or paired leaves that are nothing more than clear-topped blobs, and Gethyllis species with narrow leaves that forms spheres of tightly knit spirals. There are crassula species here, with thick, white leaves like the chunks of quartz, miniature aloes, intensely succulent, stocky armed medusa-type euphorbias, dwarfed Sarcocaulons (now called Monsonia, members of the Geranium family), and a wealth of succulent genera such as Anacampseros, Adromischus, Othonna, and more unlikely-looking bulbs, such as the thick-leafed Lachenalia anguinea. A few non-succulent plants also make their way into the quartzfields, members of the Scrophulariaceae (Snapdragon family) among them, but the denser the quartzfield, the smaller and more specialized the plants.
Between the southern Namaqualand , where smaller quartzfields exist along with the Knersvlakte, and the Richtersveld, much of the country consists of a landscape of oddly eroded granite and quartzite domes. This is the Hard Veld, a landscape of rocks, small rises called koppies, and the domes themselves, that can reach several hundred feet in height. Much of the flat land between these rock hills had been turned into farmland—it seems rich but the rains are erratic and week, and half the farms are abandoned, the old fields completely covered with opportunistic African daisies (osteospermums and other genera) that completely, almost unbelievably, carpet the land in blazing orange. Bulbs abound here, amid the rocks, including many species of Babiana, Gladiolus, Lapeirousia, as well as odder things such as Androcymbium, with bracts like glowing red cups or white piece of origami paper surrounding small flowers and Ornithoglossum, with pendent flowers that look like dark brown, purple and almost black columbines. Undisturbed land here is covered with shrubby euphorbias, larger aloes, culminating in the twenty foot tall “quivertree” or “Kokerboom,” Aloe dichotoma, and succulent pelargoniums. The potholed ridges of the domes support unique populations of miniature crassulas and conophytums, while at the summits, where water pools up for awhile during the cool months, a surprisingly lush flora manages to thrive, with sarcocaulons densely leafed, three feet tall and four feet wide, twined about with the vining Pelargonium praemorsum, with wide open, four inch flowers, white with purple and red stripes that look like butterflies. Sedges and ferns also cluster around these very temporary water holes on the dome tops. Descending the crumbling, curving, steep slopes can be an interesting experience, and you may end up quite a distance from where you expected.
The Sand Veld is the area right along the coast, beach sand that’s far enough from the present shoreline to support plant growth of a fashion. There’s a surprising variety that stays right near the coast, several species of aloe, the strongly tubercled upright growing clubs of Euphorbia schoenlandii as well as spiky small-growing shrublike species, an array of clustering grape-like conophytums, Moraea species and other bulbs. Farther north into Namaqualand , the Sand Veld changes as it merges with the bleak landscape of the Richtersveld, and I’ll discuss this land of diamond mines, forbidden zones, and Dr. Seuss plants in the next column.
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