Description
This medium-sized, semi-deciduous tree with a round crown occurs at low altitudes. It grows up to 18 m in height. The tree is commonly known for its toxic milky latex that exudes from all parts of it. Its characteristic bark is dark brown to black, thick, rough and neatly cracked into regular rectangular blocks that are arranged in longitudinal rows. Leaves are alternate, simple and are up to 70 x 35 mm and the margins are finely toothed. The young, red leaves are often visible among the older, green leaves in spring. The flower heads are 15-30 mm long, bearing mostly male and a few female flowers. The female flowers are attached at the base of each spike. Flowering takes place in August to September before the new leaves appear. The flowering spikes of this plant are unusual in appearance as the male flowers appear gold-coloured because of the pollen whereas female flowers are blood red. The flowers are visited by bees. The fruit is a capsule that is three-lobed and opens with an exploding sound that can be heard on hot summer days from October to February. The Knobthorn Moth lays its eggs in the fruit and the larvae cause the fruit to jump once they have hatched. This is why they are called ‘jumping beans’.The fruit is eaten by birds, antelope and monkeys. This tree is very attractive in larger gardens, it is fairly drought and frost resistant, but grows very slowly. Although the latex is very toxic to humans it does have traditional medicinal uses, for example, a drop of the fresh latex is applied to a painful tooth as a painkiller. The bark is used to treat stomach pains but large dosages will cause damage to the internal organs. Powdered bark is rubbed all over the body to prevent having a hairy body. Wood smoke is inhaled to drive away evil spirits. Pieces of bark are worn as a protective charm and it is also used as a fish poison. It attracts birds, butterflies and is also ideal for bonsai. Antelope, stock and monkeys eat the fallen leaves while fresh leaves are eaten by Black Rhino and Elephant. Porcupine eat the bark. Although it is medicinal, all parts of this tree can cause nausea and death. The wood is hard and is used for furniture but is lethal if used for fuel. It is more fragrant than sandalwood and can be put into linen cupboards to keep fish-moths away. Even the sawdust smoke is lethal if burnt. I read of children who died after using the branches as skewers to braai their boerewors. The name is derived from the Greek speiros = spiralled or twisted ; stachys= spike as the flowers are in a tight spiral on the spike.
