The lowlands and the lower mountains, especially southward, are generally treeless.
In the lowlands of the western portion, the Chinese have introduced a large number of cultivated plants and fruit trees.
At the present time compilers of strata maps generally limit themselves to two or three colours, in various shades, with green for the lowlands, brown for the hills and blue for the sea.
Between the Harrar plateau and Cape Guardafui the coast ranges maintain a mean altitude of from 4000 to 5000 ft., and fall generally in steep escarpments down to the narrow strip of sandy lowlands skirting the Gulf of Aden.
It stands on an abrupt hill-spur rising above flat lowlands which form a southward continuation of Romney marsh.