The Old Man of the Forest

Forest Milkberry, Mugambera (Kikuyu), Munguladugi (Kamba)

Scientific name : Manilkara discolor. Family: Sapotaceae

Hidden deep in Karura Forest, the ‘Old Man of the Forest’ (Manilkara discolor) towers over the caves where Mau Mau freedom fighters hid in the 1950s. Today, in happier times, it is admired by the thousands of people who come to walk in the forest.

The tree’s English name, Forest Milkberry, refers to the milky-white liquid that it produces when it is injured. This liquid, which is called latex, dries to create a rubbery, protective layer over the injury.

Humans find latex useful too. The latex from this tree’s cousin, Manilkara chicle is used to make chewing gum chewy. Some latex (though not the Forest Milkberry’s) contains rubber - one of the most useful substances on earth (see further notes below).

There are several species of Manilkara tree growing in Kenya. People use them for making tools, building boats and for medicine. In South Africa the wood is used to make xylophone keys.


The Forest milkberry tree’s leaves grow in clusters at the end its branches. Dark green on top and silvery underneath, they give the tree its scientific name ‘discolor’,meaning to lose or change colour. Its tiny yellow flowers grow at the base of the leaves. They are pollinated by the bats that live in the cave.

The tree’s yellow fruit are juicy and delicious. They are enjoyed by fruit-eating birds, fruit bats and monkeys.

Further reading

Many trees produce latex, and some of this latex contains rubber. Humans have been using natural rubber for thousands of years. It is an essential ingredient for thousands of things we use from surgical gloves to car tyres. The most important rubber producing tree is Hevea brasiliensis comes from the Amazon. Most natural rubber today is produced in enormous plantations in Asia.

Click on this link to read an interesting article about natural rubber in Kids Frontiers in.

Not all trees produce latex when they are injured. Some produce resins like gum Arabic, Myrrh and Frankincense which are also very useful to people. You can read about tree resins here.

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