Prota 2: Vegetables/Légumes
Notizbl. Bot. Gart. Berlin-Dahlem 8: 275 (1923).
Maasai stinging nettle, forest nettle (En). Ortie massaïe (Fr). Mpupu (Sw).
Origin and geographic distribution
Urtica massaica occurs in eastern DR Congo, Rwanda, Burundi, Kenya, Uganda and northern Tanzania.
The leaves of Urtica massaica are wilted, boiled and eaten, or used young and uncooked, as is the case with several other Urtica species throughout the world. In Tanzania this vegetable is considered a famine food, but in Uganda it is locally more popular and frequently eaten.
The Maasai use the leaves to cure stomach-ache. In the Kisii area of Kenya the leaves are used to treat malaria. In Tanzania the macerated roots and leaves are used for the treatment of hepatic diseases. In Rwanda and Burundi Urtica massaica is used alone and in mixtures with other plant species to treat numerous ailments: bruises, injuries, fractures, venereal diseases, rheumatism and urethral leak. In Uganda the leaves are used as a repellent against rats and for protection of crops from grazing cattle.
No extracts of Urtica massaica that have been tested have shown any in-vitro activity against Plasmodium falciparum. A crude extract of Urtica massaica has been tested against soil pathogens (Fusarium oxysporum, Alternaria passiflorae and Aspergillus niger) but did not show biological activity against any of these pathogens. The sting of Urtica massaica is painful but wears off after a few minutes. Acetylcholine, histamine and 5-hydroxytryptamine have been implicated in itching from the stinging hairs of other Urtica species.
Dioecious, erect, perennial herb up to 2 m tall, little branched; rhizome creeping; all parts with 1.5–2 mm long stinging hairs. Leaves opposite, simple; stipules fused, interpetiolar, 1–2 cm long; petiole up to 4.5 cm long; blade ovate, 7–13 cm × 6–10.5 cm, base cordate, apex acute to shortly acuminate, margin usually double-serrate. Inflorescence an axillary, lax, cymose panicle up to 4.5 cm long, 4 at each node. Flowers unisexual, regular, 4-merous, c. 1 mm long, with free tepals in 2 unequal pairs; male flowers with 4 stamens and rudimentary ovary; female flowers sessile, with superior, ovoid, 1-celled ovary. Fruit an ovoid, flattened achene c. 1 mm long.
Urtica comprises about 80 species and is almost cosmopolitan, with most species in temperate regions of the northern hemisphere and about 5 in Africa, 2 of which are introduced weeds. Urtica simensis Hochst. ex A.Rich., an Ethiopian endemic, is also used as a vegetable; it can be distinguished by smaller stipules and simply serrate leaf margins, and it is less robust. Urtica dioica L. has been reported from tropical Africa (DR Congo, Ethiopia), probably as an introduced weed in gardens, but its presence is not confirmed by herbarium specimens. In South Africa and many other regions of the world its leaves are used as a vegetable. It is widely used medicinally in treating asthma, allergies, coughs, rheumatism, symptoms of benign prostatic hyperplasia and paralyzed limbs, and has been recommended as a diuretic and antispasmodic and to stimulate hair growth.
Urtica massaica occurs in clearings and natural open glades in rainforest and moist evergreen bushland, often near human dwellings. It is found mainly at altitudes of 1500–3250 m and is often associated with buffaloes. In grazing areas it is considered an important weed. In Uganda it is an important component of the vegetation of abandoned fields and in forest clearings where grazing takes place.
To stimulate growth of tender sprouts the old stems are cut back. Harvesting should be done with hands protected because of the stinging hairs.
Genetic resources and breeding
Urtica massaica is common in its area of distribution and not threatened with genetic erosion. A single germplasm accession is held by the National Genebank of Kenya.
As a vegetable Urtica massaica will remain important only locally. The widespread interest in other Urtica species because of their medicinal properties, combined with the many uses of Urtica massaica in traditional medicine, may eventually attract attention from phytochemical research.
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Correct citation of this article:
Bosch, C.H. & Schippers, R.R., 2004. Urtica massaica Mildbr. In: Grubben, G.J.H. & Denton, O.A. (Editors). PROTA 2: Vegetables/Légumes. [CD-Rom]. PROTA, Wageningen, Netherlands.