- Botanical: Hagenia abyssinica
- Family: Rosaceae
- Hits: 744
Known asAfrican redwood, East African Rosewood, brayera, cusso, hagenia, kousso, Kosobaum, Kossobaum
Parts Usedflowers, fruit
Stomach & Intestinaltapeworms, emetic
Dioecious, small to medium-sized tree, up to 20 m tall; bole rarely straight, up to 60(–220) cm in diameter; bark pale red-brown, flaky; crown wide, umbrella-shaped; young branches densely covered with short, villous hairs and long, erect, silvery, soft, often glandular hairs turning reddish-green, with ring-like, long persisting leaf scars. Leaves alternate, imparipinnate, up to 50 cm long; petiole up to 15 cm long, with 2, up to 1.5 cm wide, thin, leafy lateral wings (adnate stipules) at base surrounding the twig as a sheath; leaflets up to 17, alternate to subopposite, subsessile, narrowly oblong to elliptical, 9–15 cm × 2–5 cm, obliquely obtuse at base, acuminate at apex, margin serrate and long silky hairy, the teeth usually ending in a thickened gland, pinnately veined with veins prominent below and having long silky hairs; much smaller, suborbicular leaflets up to 2.5 cm in diameter may occur alternating with the normal leaflets. Inflorescence a terminal, drooping, much-branched, many-flowered panicle up to 60 cm × 30 cm, yellowish, often bright red tinged; branches villous to long silky hairy, sticky, subtended by leafy bracts, rachis usually zigzag. Flowers unisexual, regular; pedicel up to 3.5 mm long, densely hairy, subtending bracts clasping the pedicel at base, bracteoles reniform; hypanthium a conical, silky hairy tube 2–3 mm long, with 2 whorls of (4–)5 green or reddish tinged lobes (epicalyx and calyx), in male flowers epicalyx lobes smaller than calyx lobes, in female flowers larger and enlarging up to 10 mm long in fruit; petals (4–)5, vestigial, up to 1.5 mm long, alternating with the calyx lobes; stamens 15–20, filaments up to 3 mm long in male flowers, in female flowers rudimentary; pistils usually 2, free within the hypanthium, ovary with a tuft of hairs at top, style subfiliform, stigma capitate, usually only one ovary per female flower developing to fruit, in male flowers functionally sterile. Fruit a globose to ovoid achene up to 2.5 mm in diameter, with a thin, papery, pale to brown pericarp, white-hairy at top, enclosed by the dry persistent hypanthium with the epicalyx serving as wings. Seed subglobose to subovoid, only slightly smaller than the fruit, usually with a wrinkled, brown, glabrous testa.
Properties & Uses
Purgative and anthelmintic; the Abyssinians are greatly troubled with tapeworm, and Kousso is used by them to expel the worms. One dose is said to be effective in destroying both kinds of tapeworms, the taenia solium and bothriocephalus latus; but as it possesses little cathartic power the subsequent administration of a purgative is generally necessary to bring away the destroyed ectozoon. The dose of the flowers when powdered is from 4 to 5 1/2 drachms, macerated in 3 gills of lukewarm water for 15 minutes; the unstrained infusion is taken in two or three doses following each other, freely drinking lemon-juice or tamarind water before and after the doses. It is advisable to fast twenty-four or forty-eight hours before taking the drug. The operation is usually safe, effective, and quick, merely causing sometimes a slight nausea, but it has never failed to expel the worm. Occasionally emesis takes place or diuresis, and collapse follows, but cases of this sort are extremely rare. It is said in Abyssinia that honey gathered from beehives immediately the Kousso plants have flowered is very effective in teaspoonful doses as a taenicide, its effect being to poison the worms.
Native to the high-elevation Afromontane regions of central and eastern Africa. It also has a disjunct distribution in the high mountains of East Africa from Sudan and Ethiopia in the north, through Kenya, Uganda, Rwanda, Burundi, Democratic Republic of Congo, and Tanzania, to Malawi and Zambia in the south.
A volatile oil, a bitter acrid resin, tannic acid, and a bitter principle called A Kosin and B Kosin, which is found in Kousso, but thought to be decomposition products. The principle constituent of Kousso is Koso-toxin, a yellow amorphous body, possibly closely allied to filicia acid, and Rottlerin; other inactive colourless bodies are crystalline Protokosin and Kosidin.