Typha capensis is synonymous with most large as well as small freshwater bodies. These perennial, leafy aquatic plants with their distinctive velvety-brown flower-spikes are truly cosmopolitan inhabitants of southern Africa.
Typha capensis is a monoecious (having the reproductive organs in separate structures but borne on the same individual), perennial marsh herb which has a very fast colonizing habit by means of creeping rhizomes. The stems are erect and simple, and terminate in dense, cylindrical flower-spikes. The leaves are long, bluish grey to green, strap-shaped and with parallel veins. Leaves vary in length from 0.5 to 1.5 m and more.
The inflorescence is a dense spike of closely packed flowers, yellow at first, turning brown later. Flowers are unisexual and minute. The male flowers are in the upper portion and female flowers in the lower portion of the spike. The flowers themselves, lacking tepals, are reduced to 1 carpel (female flowers) or 2-5 stamens ( male flowers), packed together with hairs. The fruit is 1-seeded, minute and has many hairs which aid wind dispersal. Typha capensis flowers from December to January.
Typha capensis is such an abundant plant in South Africa, many people regard it as a pest as it is known to spread very fast. It is not in any way endangered or threatened.
Distribution and habitat
Bulrushes are found throughout the world and southern Africa. It is most common in aquatic situations whether in standing or slow-flowing waters. Marshes, stream banks, dams and lakes are most commonly inhabited by Typha capensis. The muddy substrate of these water bodies help the plants to anchor its rhizomes firmly.
Derivation of name and historical aspects
The genus name Typha is from the Greek typhos, meaning marsh, referring to the habitat, or possibly typhe, meaning cat's tail, alluding to the inflorescence. The specific name capensis is given for the Cape where it occurs in abundance.
As mentioned before, this plant is adapted to muddy and wet conditions. The strong fibrous roots that arise from the rhizomes help to anchor the plant so that it can withstand strong winds without being swept away in the water. Owing to variation in water content of marsh habitats, the rhizome structure may show both hydric (water) and xeric (dry) adaptations. In Typha the prominence of mechanical and conductive tissue indicates the plant's mesophytic (plants capable of coping with both extremes of water and drought) ability due to the presence of abundant storage parenchyma, aerenchyma, and hydrophytic tissue. The thickened endodermic layer affords a means of protection against moisture loss during drought. Since both the mechanical and conductive tissues are well developed, the plant is able to grow erect without being supported by the water. Perhaps the most distinctive feature of stems of amphibious plants like the bulrush is that they have large internal air chambers crossed by diaphragms that are pervious to air. These are particularly important to provide aeration to the submerged parts. The leaves of amphibious plants show the greatest variation in both form and structure when the plant is subjected alternately to the air and water environment.
Typha capensis is an important plant for many species of birds that are closely associated with water. The dense stems provide ideal shelter and nesting opportunities for birds such as the Moorhen (Gallinula chloropus), African Black Duck (Anus sparsa), the Red Bishop (Euplectes orix), Yellowrumped Widow (Euplectus capensis), and the Common Waxbill. The submerged stems of bulrushes provide ideal nurseries for hatchlings of several freshwater fish species not to mention frogs, toads, terrapins and other aquatic organisms.
Uses and cultural aspects
A decoction of the rhizomes is used for venereal diseases or during pregnancy to ensure easy delivery: decoctions are taken orally or applied externally to promote expulsion of the placenta. It is also said to strengthen uterine contractions. It is also taken to promote fertility in women, to enhance male potency and libido, to improve circulation and for diarrhoea and dysentery. The fleshy, spongy rhizomes are dug up and may be pounded to a meal and used as a source of starch. The pollen may also be used as a high-protein food. The leaves are used to make hand brooms and are also used to some extent in weaving and thatching.
At a symposium on Typha held in cape Town in 1989, it was reported that Typha, despite its potential to be an invader, does have several economic benefits. It can be used as a subsistence crop as all parts of the plant can be eaten and is grown as a speciality food source in America. The pollen is used to produce a plant growth regulator in Japan. Aside from traditional medicinal uses as outlined above, the plant can also be used for craft work and house building. Leaves were used for caulking barrels and for insulating the roofs of early houses at the Cape.
After dipping in kerosene the female inflorescences can be used as torches, or they can used as decorative dry flowers. The floss can be used for stuffing and padding.
The plants have also been used to make paper in South America. The plant can also be used for water purification and green manure.
Growing Typha capensis
Typha capensis can be grown by dividing the large clumps. The fast-growing rhizomes spread quickly and soon form large clumps of leaves. It will only grow well where the soil is under the water or very wet. It can, if necessary, be controlled by chopping back new rhizomes. To make maintenance easier and to manage growth, plant bulrushes in separate containers which may then be submerged. When necessary, remove the container from the water and cut back the plant and replace in the water.
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Harold Porter NBG