DROUGHT SURVIVORS

We walked along a ridge on one of the nearby hills the other afternoon and were struck by the shrubs, flowers and succulents that have managed to survive not only a devastating fire that burned the area about a year ago, but the current severe drought conditions and the number of cattle that pass through the area from time to time – part of the Urban Herd I keep mentioning. These drought survivors are proof that it is best to focus on indigenous plants for one’s garden. I will focus on three of the succulents that we came across in the veld.

The first is Faucaria tigrina also known as Tiger’s Jaw.

It was exciting to come across these plants that are endemic to the Grahamstown area. They grow in Albany Thicket as well as on open sandstone patches and among rocks. Rather frighteningly though, they have become such an endangered species that they have been listed in the Red List of South African Plants! This is largely because their natural habitat is shrinking due to urban expansion as well as overgrazing.

As you can see, they grow in clumps of stemless, star-shaped rosettes with the threadlike structures that collect water vapour from the surrounding air and direct it down toward the roots of the plant. The seeds are borne in hard fruit capsules. The many whitish flecks on the reddish leaves resemble the lichens and reddish rocks in its natural surroundings – a good camouflage for, except for those growing in bare patches, they were difficult to see. Here is a picture of a lichen-covered rock nearby:

The first documented discovery of Faucaria tigrina was during an expedition in 1789 by Francis Masson, who collected plants for Kew Royal Botanical Gardens, where they were named by Adrian Haworth. The genus name comes from the Latin word faux meaning jaw and tigrina for tiger.

While on the subject of Adrian Haworth, the next interesting succulent is the Haworthia reinwardtii, commonly called Haworthia or as Zebra Wart. This genus is named after the same Adrian Haworth mentioned above in 1821.

These plants are also indigenous to the Eastern Cape, occurring south to south-east of Grahamstown between the Kowie and Fish Rivers and eastwards from the Fish River towards East London. They typically grow on dry rocky hillsides, often under taller emergent shrubs, or in the shade of rocks. It was disturbing to find a number of these plants had obviously become uprooted by cattle passing through the area – that Urban Herd again!

As you can tell from the photograph, the tightly-packed, columnar rosettes of this plant are comprised of small, pointy, fleshy leaves of dark green marked with bumpy, raised white bands that form a rosette. The mature specimens form into spreading clumps of numerous small rosettes connected by fleshy, fibrous roots.

The last of the succulents I want to show you is the Euphorbia obesa, also called a Zulu Hut or Baseball plant. This was a particularly exciting find out here in the veld, not only because they are so well camouflaged that they can be very difficult to see, but because they too are endangered. They are slow-growing and have been subjected to illegal over-collection in their native habitat – also in the Eastern Cape – and are now protected by national (Nature Conservation) and international (CITES) legislation and may not be removed from its natural habitat.

These plants contain water reservoirs that see to their survival during times of drought. Their preferred habitat is very stony and hilly and they grow in full sun or in partial shade. Young plants resemble a sea-urchin in shape, while older plants can become elongated. The flowers are produced on fork-branched peduncles – the dry remnants of which can be seen in the next photograph.

Professor Peter Macowan (1830-1909), a botanist from Gill College in Somerset East, discovered Euphorbia obesa growing near Graaff-Reinet in 1897. He collected this peculiar ball shaped succulent plant and sent it to the Royal Botanical Gardens, Kew, where the plant named by Joseph Dalton Hooker (1817-1911).

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