These are generally unproductive, and covered with stunted wood; but the lower country is fertile, and] finely clothed with the baobab, the tamarind and various valuable fruit-trees.
The principal cultivated plants, apart from sugar-cane and coffee, are rice (in great variety of kinds), the coco-nut palm, the areng palm, the areca and the sago palms, maize, yams, and sweet potatoes; and among the fruit trees are the Indian tamarind, pomegranate, guava, papaw, orange and lemon.
The tamarind and banyan are also noteworthy.
Near the hills and along the streams are strips and patches of jungle; the villages are usually surrounded with picturesque groves of tamarind, mango and other shadegiving trees.
It is planted in terraces on the mountain slopes; shady trees, such as tamarind and fig, are planted in the border as a protection from the sun, and the terraces are irrigated by channels led from a neighbouring rivulet or spring.
Among cultivated fruits are the following: - Mango (Mangifera indica), plantain (Musa paradisiaca), pine-apple (Ananassa sativa), pomegranate (Punica Granatum), guava (Psidium pomiferum and P. pyriferum), tamarind (Tamarindus indica), jack (Artocarpus integrifolia), custard-apple (Anona squamosa), papaw (Carica Papaya), shaddock (Citrus decumana), and several varieties of fig, melon, orange, lime and citron.
Other trees, found chiefly on the plateaus, are the baobab, the shea-butter tree, the locust tree, gambier, palms, including the date and dum palm (Hyphaene), the tamarind, and, in the arid regions, the acacia and mimosa.
The forests contain valuable timber trees such as African oak or teak (Oldfieldia Africana), rosewood, ebony, tamarind, camwood, odum - whose wood resists the attacks of termites - and the tolmgah or brimstone tree.
As a whole, the arable tract is a treeless region, except around the villages, which are encircled by fine mango, pipal, banyan and tamarind trees, and intersected with green shady lanes of bamboo.
The forest vegetation, largely confined to the "Isle of Isles" and the southern uplands, includes the Adansonia (baobab), which in the Fazogli district attains gigantic proportions, the tamarind, of which bread is made, the deleb palm, several valuable gum trees (whence the term Sennari often applied in Egypt to gumarabic), some dyewoods, ebony, ironwood and many varieties of acacia.
On the western side of the island the baobab, the tamarind, the rotra (Eugenia sp.), the rofia palm, and several species of fan-palm (Hyphaene) and of Ficus are prominent; and the mango (introduced) grows to a large tree.
Various other adulterants are sometimes used, such as the inspissated juice of the prickly pear, extracts from tobacco, stramonium and hemp, pulp of the tamarind and bael fruit, mahwah flowers and gums of different kinds.
Of plants that furnish food for man the most important are rice, maize and millet, coffee, the coco-nut tree, sago-palm, the obi or native potato, the bread-fruit and the tamarind; with lemons, oranges, mangosteens, wild-plums, Spanish pepper, beans, melons and sugar-cane.