Close to Shwaib the topography is extremely varied, with sand dunes, gravel plain and mountain. The border with Oman is approached across the stony alluvial plain running parallel to the Hajar mountains.
Small farms and agricultural plots are present, with newly constructed low-cost housing oriented to see the sunrise over the mountains. Ghaf (Prosopis cineraria) trees are a characteristic feature of the landscape, growing on both the plains
and in sand dune terrain.
The large grey-green round-leaved Sodom’s apple (Calotropis procera) has beautiful waxy flowers. A member of the milkweed family, Asclepiadaceae, it has a poisonous milky sap and is not grazed. It is, however, valuable to wildlife, being the larval food plant of the widespread plain tiger (Danaus chrysippus) butterfly. The larvae clearly do not suffer from the effects of the latex and, moreover, are able to store the poison not just during the larval stage but into adult life. This confers protection from would-be predators and as a consequence the female (only) of a non-poisonous butterfly, the unrelated Diadem (Hypolimnas misippus) has come to mimic the plain tiger.