Foraging in Nairobi

Know these first

What can hurt you around Nairobi in October

6 species on our hazard list have been recorded near here this month, 4 of which can kill a healthy adult. Learn these before you learn anything you intend to eat.

• Can kill24 records nearby

  Castor oil plant

  Ricinus communis

  Mistaken for

  Its mottled seeds look like beans, or like fat ticks, and children pick them up; it grows as a weed on riverbanks, roadsides and rubbish heaps across Africa.

  How to tell

  Big, glossy, hand-shaped leaves with five to eleven pointed, toothed lobes, often flushed red; spiny three-lobed seed capsules; and smooth, shiny, bean-like seeds mottled brown and grey with a small pale cap at one end.

  What it does

  Ricin. Four to eight chewed seeds are considered a lethal dose for an adult: burning mouth, then bloody diarrhoea, dehydration and collapse over several days. Seeds swallowed whole may pass unbroken, but never count on it.

• Can kill7 records nearby

  Oleander

  Nerium oleander

  Mistaken for

  Nothing edible, but it is planted along roads and in gardens everywhere, and its straight green stems look like ready-made braai skewers.

  How to tell

  A shrub with long, narrow, leathery leaves in pairs or threes, each with a strong pale midrib; clusters of pink, white or red flowers; and long, thin pods of fluffy seeds.

  What it does

  Cardiac glycosides in every part. It is bitter, so serious poisoning is uncommon, but toddlers have died after eating the leaves. Never use its stems as skewers or its leaves for tea.

• Can kill4 records nearby

  Thorn apple (Datura)

  Datura (the whole genus)

  Mistaken for

  Young plants come up among amaranth (morogo) and other wild greens in maize fields and gardens, and children eat the seeds.

  How to tell

  A coarse, rank-smelling plant with large, irregularly toothed leaves, big upright trumpet flowers, white or purple, and a spiny, walnut-sized capsule packed with small dark seeds. Amaranth has smooth-edged leaves and only bristly flower spikes.

  What it does

  Atropine and scopolamine: dry mouth, hot flushed skin, a racing heart, huge pupils, then delirium and hallucinations that can last a day or more. It has killed adults and children.

• Can kill4 records nearby

  Yellow oleander

  Cascabela thevetia

  Mistaken for

  Nothing edible, but it is a common hedge and garden shrub across tropical Africa, and children play with the hard seeds.

  How to tell

  Narrow, glossy, willow-like leaves; funnel-shaped flowers, usually yellow, sometimes apricot or white; and a fleshy fruit that ripens red to black around one large, hard seed. Twigs bleed milky sap.

  What it does

  Cardiac glycosides that drying and cooking do not destroy: vomiting, then a dangerously slow, irregular heartbeat. Every part is toxic; swallowing the seeds is a common means of suicide in South Asia.

• Hospital30 records nearby

  Euphorbias (milk bushes, naboom, pencil tree)

  Euphorbia (the whole genus)

  Mistaken for

  Prickly pear and other cacti — many African euphorbias are spiny, leafless succulents that look exactly like cacti — and the pencil-stick hedges of Euphorbia tirucalli around farms and villages.

  How to tell

  Break a stem: a euphorbia bleeds white milky latex at once. Cacti such as prickly pear bleed clear or slimy sap, and their spines grow from small fuzzy cushions; euphorbia spines grow singly or in pairs, never from a cushion.

  What it does

  The latex burns skin and mouth, and in the eye can cause temporary blindness. Wear gloves and eye protection near a cut plant, and never rub your eyes.

• Hospital29 records nearby

  Lantana (tickberry)

  Lantana camara

  Mistaken for

  Blackberry-like clusters of small dark berries that children pick; it smothers forest edges, roadsides and farmland across East and southern Africa.

  How to tell

  A scrambling shrub with square, prickly stems, rough leaves that smell sharp when crushed, flat clusters of tiny flowers that change colour as they age (yellow to orange, pink or red), and tight bunches of small berries ripening green to glossy purple-black.

  What it does

  The green, unripe berries are the dangerous ones: vomiting, diarrhoea and difficulty breathing have been reported in people. Livestock that eat the leaves suffer liver damage and severe sunburn.

These are recorded within about 40 km of here in this month, from verified public observations. It is not a complete list of what is dangerous — nothing is — and a species missing from it may still be in your woods. Never eat anything identified from a photograph and a description alone.