A portion of gassa tree
Gassa is a wild growing multipurpose tree from East Africa. It grows naturally at altitudes ranging between 500 to 1500 metres in Ethiopia, Somalia and Some parts of Kenya, Sudan and Uganda too. The fruits are edible and eaten during normal times but more at the time of food shortage.
Gassa trees are also planted by farmers as shade trees in homes as well as gardens in Bedessa woreda (district) of Ethiopia.
A tall tree with spreading crown, upto 35 m high, with long straight cylindrical or slightly fluted bole; bark grey-brown, rough and finely fissured; young shoots subglabrous, usually with pale raised lenticels.
A herbarium specimen of gassa
Leaves elliptic to oblanceolate, rarely ± obovate, 8–17 cm long, 3–6.3 cm wide, upper third of leaf tapering to acuminate apex (especially in crown leaves), rarely acute or ± obtuse, narrowly to broadly cuneate, thinly coriaceous, dull green above, greyish-green beneath with a sparse indumentum of minute closely appressed hairs; lateral nerves ascending, finely raised, looped near margin, intracostal veins present; petioles l–3 cm long, glabrous.
Flowers 1–6, congested in axils of current leaves; pedicels stiffly erect or horizontal, 8–12 mm. long, puberulous; calyx up to 5 mm long, ± densely pubescent; lobes fused at base forming a cupular structure up to 2 mm long, outer lobes ovate, up to 3 mm wide, inner lobes slightly smaller; corolla pale yellow, tube 1.5–2 mm long; outer lobes narrowly lanceolate, up to 5.5 mm. long; median lobe elliptic, up to 5.5 mm. long; filaments 2.5–3 mm long, anthers up to 2 mm long; staminodes narrowly oblong to ligulate, up to 2 mm long, apex with 1–3 (usually 2) slender laciniate processes up to 2 mm long; ovary depressed globose, pubescent, 10–12-locular; style 6–8 mm. long, with a base ± swollen and pubescent.
Fruits subglobose, up to 3 cm. in diameter, glabrous, with milky pulp.
Seed shiny brown, ± obovoid and flattened, 1.3–1.7 cm long, 7–8.5 mm wide; hilum lateral, oblique and extending to base.
The fruits are edible and eaten by local people.
Gassa is a good shade tree and therefore planted by people, especially farmers, for shade.
Other popular uses of gassa trees are firewood, timber for heavy constructuions, farm tools and tool handles. The wood is very hard to saw and often has rot in the heartwood, tending to split with nailing, but very strong and durable. It has been used for flooring, spear shafts, building and electric poles. As it does not rot in water, it has also been used for boat and bridge construction.
Gassa trees are raised from seed. As one can find plenty of wild seedlings below the large trees, so these are also collected.
The seedlings have to be protected for a couple of years. These are then left to nature.