Gomphocarpus cancellatus

Gomphocarpus cancellatus, previously Asclepias cancellata, stands out among competing vegetation due to the erect stems that become 1,5 m tall, its big leaves and unusual flowers.

G. cancellatus has, like other unusual or remarkable plant, accumulated a number of descriptive names in popular parlance. These include bergmelkbos (mountain milk bush), regopmelkbos (erect milk bush) and dermhout (intestine wood). Each of these refers to some noted feature of the plant. Melkbos is a common name given to many plants containing milky latex, this species being one of them. Leaves drop off to leave lower stems pale grey and bare, resembling intestines.

The leaves of G. cancellatus are opposite, ovate to oblong, leathery and sometimes thinly fleshy. The leaf surface may be hairy or not. Its midrib and lateral veins are whitish and conspicuous, although not always. Leaf colour is dull green and sometimes shiny. The lower surface is often whitish. The lateral veins curve inwards towards the tip in a regular pattern, sometimes about invisible. The margins are entire, sometimes reddish. The leaf tip tapers to a point or is sometimes rounded with a small mucro protruding at the tip. The leaf base is rounded.

The species distribution is in the Northern Cape across Namaqualand in a broad coastal swathe to the Cape Peninsula and Table Mountain in the Western Cape, eastwards along the southern coast and the Little Karoo to the Eastern Cape as far as Gqeberha; also occurring in Namibia.

The habitat is stony slopes in fynbos, succulent Karoo, Albany thicket and other, often semi-arid scrub. The species is not considered to be threatened in its habitat early in the twenty first century (Clarke and Mackenzie, 2007; Manning, 2007; Bean and Johns, 2005; http://redlist.sanbi.org).