Optimising Pesticidal Plants: Technology Innovation, Outreach and Networks

Fruit-bearing Zanha africana tree

Distribution and habitat

Z. africana is found in open woodlands, on granite ridges and sometimes in riverine forests, at 600-1550m altitude, in Kenya, Angola, Mozambique, South Africa, Zimbabwe, Tanzania and Democratic Republic of Congo. In Kenya it occurs in open woodlands and farms, in wooded grasslands in Kiangombe, Makueni and Katumani.

Flowering and fruiting habits

It is a tall shrub or small tree 12-17m tall, bole branchless up to 6m with reddish to brown bark, scaling off in large flakes. Crown open with erect branches; twigs hairy when young. Leaves are alternate, compound with 3-6(-8) pairs of leaflets, stipules absent, petiole 1-5cm long. Inflorescence is terminal or axillary panicle with flowers in dense clusters. Flowers are unisexual, regular, small, greenish, sweet scented, 2.5mm long. Fruit is ellipsoid fleshy drupe reaching 2cm x 2cm, velvety, hairy, yellow to bright orange with one seed which is ellipsoid up to 1.5cm x 1cm.

Uses other than pesticidal

Timber- Wood is used for construction, door frames, tool handles, flooring, ship building, furniture, toys and agricultural implements.

Food- The fruits are eaten by man but can cause severe diarrhoea in eaten in excess. Seeds can be poisonous.

Soap- Saponins are present in root bark, stem bark and fruits.

Medicinal- Traditionally used as a medicine in many African countries. In Tanzania, root decoction used to facilitate child birth, treat constipation and fits. Root preparations are also used to treat toothache, rheumatic pains, pneumonia, vertigo, fungal infections headaches, colds and fever Fodder- Leaves are eaten by cattle, goats and sheep.

Apiculture- The tree is planted for nectar for honey bees.

Propagation and cultivation

Propagation is done with fresh seeds which are recalcitrant. Propagation has been shown to be successful with root and stem cuttings.

Seed collection & Storage

Fruits are collected when mature. Seeds are harvested by hand. Seeds are recalcitrant and should be used fresh. Care should be taken as seeds can be poisonous.

Recalcitrant seeds cannot be stored for long periods of time.

Parts used

Root bark

Preparation

Dry and grind

Uses

Can be used both pre and post-harvest

Target organisms

Against broad range of insects, mainly in storage