IN THE GARDEN
From page 31 conditions. All parts of the plant are poisonous when ingested, and handling the plants may irritate or even blister the skin. Small infestations can be removed mechanically, but all seed pods should first be removed to prevent recolonisation, and gloves should be worn to protect the skin. Once the plants have been removed, ensure that the entire rhizome has also been removed be-cause any remnants will merely regrow. Removed plants can be burnt or allowed to rot in black bags in the sun to prevent them from re-growing where they are discarded. Smallholders are urged not to plant this species but rather to grow the indigenous yellow vlei iris, Moraea huttoni, which also produces attractive, yellow flowers, and can be used in similar situations. Another ornamental alien that has escaped cultivation to become invasive in many parts of the country is the Madagascar Periwinkle( Catharanthus roseus), a declared invader in South Africa which must be controlled, or eradicated where possible. It is an erect, perennial plant up to one metre high, with a
Butterfly Bush
Madagascar Periwinkle
woody base. The leaves are bright green and glossy, with attractive pink or white flowers in the axils. Each flower has five petals that fuse to form a tube at the base. Plants flower throughout the year. Infestations can be removed by hand-pulling. Gloves should be worn to protect the skin from the latex, and all seeds must first be removed from the plants to prevent them from germinating in the disturbed soil. The collected seeds must be destroyed, preferably by burning. Herbicides designed for broad-leafed plants may be used. The third member of this terrible trio is the Butterfly Bush( Oenothera lindheimeri), which is a perennial herbaceous plant native to parts of North America, which was imported into South Africa as a garden ornamental. It grows upright and spreads in a grass-like manner from a woody root-stock, and can reach as high as one metre. Attractive, butterfly-shaped flowers are borne in spikes, and open at sunrise in sequence along long stems. Owing to the fact that
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