Read it through once

It is upon the actual bank itself, which is a gentle slope of ten to fifteen feet, that Lupines, Lubia beans, and other plants are regularly cultivated. This narrow green ribbon remains almost always on each bank. Where the cliffs recede, one notices a line of tall, graceful date palms, mixed occasionally with the branched Dôm palm (the nut of which yields vegetable ivory).[66] Tamarisks, conspicuous for their confused, silvery-green foliage, can be noticed here and there. The Acacias are common enough, and sometimes one of them is used as a hedge. It is a spreading, intricately-branched little shrub, with very white branches and stout curved thorns.