The rocky ridges of the great plateau, destitute of all vegetable mold, are wholly bare and arid, admitting not the slightest degree of cultivation.
Many of the mountains of Azerbijan, naked, rigid, and furrowed, may compare even with these desert ranges for sterility.

The higher parts of Zagros and Elburz are sometimes of the same character; but more often they are thickly clothed with forests, affording excellent timber and other valuable commodities.

In the Elburz pines are found near the summit, while lower down there occur, first the wild almond and the dwarf oak, and then the usual timber-trees of the country, the Oriental plane, the willow, the poplar, and the walnut.

The walnut grows to a large size both here and in Azerbijan, but the poplar is the wood most commonly used for building purposes.

In Zagros, besides most of these trees, the ash and the terebinth or turpentine-tree are common; the oak bears gall-nuts of a large size; and the gum-tragacanth plant frequently clothes the mountain-sides.