The Leaves are borne spirally round the branches, often in the thorn axils or on the thorns themselves, or on twigs bare of thorns. They are bifoliate, typical of the genus, rarely over an inch long and mostly a ½ inch, the terminal leaf of a new shoot often being much larger. The mid-rib is extended between the leaflets which are divided to the base and there are three main nerves to each leaflet. They are a light, blue-green or grey-green, with a bloom and are partly sensitive, closing up rapidly after being plucked.
The Flowers are white and can be found all the year round, though the proper flowering season is in the rains or towards the end of them. They are in small racemes at the twig ends, pendulous amongst the leaves, ¾ inch long, with a calyx which splits partially into five parts, remaining attached at the tips and opening beneath, 5 white petals, spoon-shaped with narrow base and broad, pointed tip, 10 white stamens with light brown anthers and a tuft of hairs at the base of each, and a clubbed pistil.
The Fruits are pods about 3 inches long, constricted between the seeds, dull black, slightly curved, containing up to eight shiny, rich red-brown seeds, roughly rectangular with one rounded corner. The seeds rattle loose in the pod which falls entire and rots on the ground. The pods hang in conspicuous clusters and may be seen all the year round.
Uses.—The bark is stripped for binding but is not plaited into ropes.
BERLINIA AURICULATA Benth.—Doka rafi. LEGUMINOSAE.
This is a medium-sized tree of the best savannah types, commonly found in “kurmis” and extending as far north as 11°. It occurs plentifully in Sokoto and Kontagora along the small streams in the south. Averaging 40 feet in height it will reach 60 feet with girths of 8-10 feet. The crown is high, rounded and very dense in the open; flatter and more superficial in heavy forest, topping a 30-feet bole, only 10 feet long in open situations. The flowers and pods are both conspicuous.
The Bark is dark-grey or brown, the scales leaving large, concave scars. The slash is pale brown.
The Wood.—The heartwood is red-brown, the sapwood light with a pink tint. In transverse section the rings are well but unevenly marked red lines. The pores are large and solitary, for the most part in oblique rows, and the rays are extremely fine and invisible to the unaided eye. In vertical section the pores are long and straight and the rings show as dark bands. It is rather a coarse, stringy wood, sawing roughly and picking up in long fibres under the plane. Where the grain suits the plane the finish has a bronze sheen. It is a fairly hard wood and weighs 50 lbs. a cubic foot.