Jumping seed tree

The Jumping Seed tree, Sapium ellipticum.

Local names: Kikuyu: Muhathi, Muthathi, Luhya: Mugoso, Luo: Amoyo, Nandi: Mseset, Samburu: Ngereni

The jumping seed tree grows in wet forest or near water at altitudes of between 1000 and 2100 metres. It could often be found it growing around forest edges but is becoming less common because of habitat loss. The tree in this picture is growing in a Nairobi garden in an area that used to be moist forest.

It is a small to medium-sized tree which can grow up to 20 m. It has a single trunk which can be crooked. The branches droop down giving it a spreading crown.  The bark feels rough to the touch but is not cracked.

The leaves  of the Jumping Seed tree are simple, alternate on the branch with many leaves on one branch.  Leaves can be up to 14 cm long with a 1 cm petiole. They are oval shaped, with serrated edges (like a saw). They are shiny dark green on top and lighter underneath and turn dark red before falling.  They feel glabrous (smooth and hairless). The veins are pinnate. There is no stipule.

The flowers are in spikes 5 – 10 cm long. The upper part are tiny male flowers with yellow stamens.  At the base are 2-5 female flowers which are larger on longer stalks. Jumping Seed trees are monoecious having both male and female flowers.

The fruit is a two part red capsule. They are often eaten by insect larvae which move around in the seed making it look as though the seed is jumping.  

The Jumping Seed tree produces latex which gives it its other English name – milk tree.  Only seven families of Kenyan trees have latex so this is a good way to recognise a tree.  The latex is poisonous and was used by hunters in Kenya to poison arrow tips.

The Jumping Seed tree is important for medicine and its leaves are protein-rich and enjoyed by animals.