The Wood is whitish, a brown colour being given it by the lines of hard tissue. It is apt to discolour with mould. In transverse section the close concentric rings of hard and soft tissue are very distinct, the pores are very numerous in the bands of soft tissue of varying width, the alternating bands of hard tissue being almost free of pores. The rays are straight, the larger plainly visible, the finer often closer together, showing as light-reflecting bands in radial section. In tangential section the hard tissue makes a well-defined grain of light brown. The wood is soft, the grain coarse; it works easily with tools, the plane giving a rough finish. Weight 50 lbs. a cubic foot.
The Leaves are bipinnate, about 2 inches long with 6-8 pairs of pinnae cut up into some 15 pairs of leaflets. There are typically three in the angle of each pair of thorns and they are dark green when full grown.
The Flowers are in yellow balls about ½ inch in diameter, 1-4 in the axil of a leaf. They have 1½ inch stalks, are sweet scented and appear from January onwards in masses which make the tree all yellow at a distance. The young leaves appear just as the flowers are going.
The Fruits are slightly curved, flat, jointed, embossed pods, 3-5 inches long, light brown with green tinges and finely veined. When ripe the pod splits up both edges, and the seeds, 6-10 in number, remain fastened to the edges by the long twisted attachments, from which they break loose gradually, the pod sections remaining attached to the tree for some time before this occurs. Many pods fall with the seeds still attached to them. The clusters of curved, split pods are most conspicuous and they contract considerably during the ripening stages.
ACACIA SIEBERIANA DC.—Fara kaya, Bauji. LEGUMINOSAE.
This common and widely distributed species has, when full-grown, some similarity to Acacia campylacantha, especially when the species occur in the open. Its long, white thorns distinguish it from the latter. It is occasionally met with as pure forest, but should not be confused with Acacia Seyal, the “Talh” acacia, which is very like the small A. Sieberiana and has yellow flower-balls and ochrey bark. Old trees are a height of about 50 or more feet with girths of 5-6 feet. They have large round crowns and sometimes rather persistent lower twigs, though 20 feet boles are not uncommon. It grows well in dry situations and frequently occurs, mixed with A. Seyal, in open, dry country.
The Bark of young trees is yellowish and smooth, this feature persisting on the branches of older trees, which have rough, small, square scales, grey in colour on the stem and larger limbs. The bark exudes a gum which is white, clear and brittle when dry, making a fair mucilage. The slash is yellow, with dark red edges.
The Thorns, persistent everywhere except on the bole and largest limbs, are fine, straight and white, with very acute points. They are in pairs at about 120° to each other, pointing slightly forward, up to 3 inches long. On new shoots they are green and soft, hardening as the shoot ages. Quite small thorns are found at the tip of the shoots.