Kigelia africana

  • Sausage Tree (E)
  • Cucumber Tree (E)
  • Worsboom (A)
  • Umbongothi (Z)
  • Modukguhlu (NS)
  • Mubvevha (V)

Description

  • The only species of its genus, found only on the African continent, this medium to very large tree has one of the richest and most diverse legacies of all our indigenous trees, and is regarded as sacred by numerous communities. Many religious meetings are held underneath the tree, and it is usually protected where other trees are cut down. The typically short and squat trunk is beautifully grooved and twisted on older trees, with a lovely, light pastel grey, flaky bark and a densely leafy, elegantly rounded crown of large, shining leaves. The trees tend to form a low spreading canopy, and become festooned with masses of very large, dark scarlet to maroon, tubular flowers that adorn the tree on long, pendulous stalks, and overflow with copious amounts of sweet nectar. The enormous, grey-green, cylindrical fruits that follow hang from the branches on sturdy, elongated strings, and are an invaluable source of food for many animals. The trees are a truly spectacular sight both in flower and fruit.

SA Tree

  • 678

Family

  • Bignoniaceae (The Jacaranda, Trumpet creeper or Catalpa family)
  • Commonly known as the Bignonias, this is a fairly large family of flowering plants belonging to the Lamiales order.
  • They have a nearly cosmopolitan distribution, but are mainly found in the tropical and subtropical, temperate parts of the world, with the greatest diversity occurring in tropical South America.
  • A few different counts exist, but the leatest research has narrowed the family down to about 80 genera and somewhat 860 species of trees, woody shrubs and subshrubs, many vines and a few herbaceous plants that frequent high altitude, montane habitats.
  • The most common members are the woody vines, and they form an important part of tropical forest ecosystems. The vines belonging to this family can easily be recognised by their prominent leaf tendrils.
  • Members can be characterised by their oppositely paired, usually bipinnately compound leaves and capsuled fruits.
  • A select few genera still bear leathery berries.
  • The flowers are typically large, bilaterally symmetric, bisexual and bell or funnel shaped.
  • Many species yield excellent timber and are prized for their decorative and/or medicinal and practical uses.
  • Some species are known to contain poisonous substances.

Habitat

  • Widespread in tropical Africa and the north eastern parts of south Africa, from the coast to elevations of about 2800 m.
  • They frequent moist, warm areas, and are often found in deep, alluvial soils near rivers and streams.
  • The trees also grow in wet savannah-woodlands and associated bushveld, as well as floodplains and riverine fringes in Natal, Transkei, warmer parts of Gauteng, Mpumalanga and Swaziland.
  • The trees prefer areas with a mean annual rainfall in the range of 800 – 2 000 mm.

Bark

  • Thick, light brown to grey, smooth on younger trees, often flaking in thin round patches or longitudinal fissures on older specimens.

  • The main stem is typically straight, short and thickset, with a diameter of 600-1000 mm.

Foliage

  • Semi-deciduous.

  • (The tree is evergreen where rainfall occurs throughout the year, but deciduous where there is a long dry season.)

  • Large, compound (200-380 mm), opposite or 3-whorled leaves, typically growing in clusters from the ends of branchlets.

  • Each leaf consists of 4-6 pairs of, large, oblong to broadly elliptic-ovate leaflets (30-180 x 25-110 mm), plus an unpaired, terminal one.

  • The basal leaflet pairs are typically much smaller than the more terminal pairs.

  • The leaves have a hard, stiff and leathery texture, with a layer of fine to rough hairs on both surfaces.

  • Above, they have a lovely, olive-grey to yellowish-green colouring, while below they are paler green, with prominent, raised lateral veins.

  • The margins are finely and obscurely toothed, often distinctly wavy, and taper to a broadly rounded or pointed tip.

  • Fresh growth is a beautiful, coppery-red, turning bright green with age.

  • The leafstalk generally has a length of between 8 & 15 cm.

Flowers

  • Large, striking, trumpet-shaped, dark-red to maroon flowers, with heavy, bright yellow veins on the outsides, carried on lax, 5-12 flowered, drooping, pendulous sprays of up to 900 mm each.
  • The flowers are each held erect in a conspicuous, cup-like calyx.
  • They have velvety insides, crinkly petals and a somewhat asymmetric shape, curving up and in around the edges.
  • About 50 bisexual flower buds are produced per stalk, and they open at night and fall the next day, in succession.
  • They are short-lived, and as soon as one flower has been pollinated, the other buds on the same inflorescence will usually abort to avoid the simultaneous development of too many heavy fruits at the same time. (Late September- October)

Fruit

  • A very large (1000 x 180 mm), hard, oblong-cylindrical, sausage-shaped, indehiscent drupe.
  • The fruits are grey to greyish-brown in colour, and are often heavily dotted with small, raised lenticels when young.
  • Long, sturdy, fibrous stalks support the hanging fruits, and each can weigh up to 10 kg.
  • The insides contain a heavily fibrous pulp and numerous small, round, brown seeds. (December – June)

Height

  • 3-20 m

Spread

  • 4-10 m

Medicinal

  • This tree truly has a mind-boggling amount of medicinal and cosmetic uses, and various pharmacological investigations have confirmed the presence of bioactive constituents in nearly all parts of the plant.
  • Research has confirmed numerous anti-inflammatory, analgesic, antioxidant, anticancer, antibacterial, antifungal, antidiarrheal, antidiabetic, anticonvulsant (anti-seizure effects) and CNS stimulating properties.
  • The unripe fruits are used as a vermifuge and in the treatment of piles and are also made into a poultice to treat rheumatism and pain.
  • The desiccated and pulverized fruits are commonly used as a disinfectant, and topical applications are said to treat skin cancer, sores, wounds, ulcers, abscesses, psoriasis, fungal infections, eczema and acne.
  • The antimicrobial and soothing properties of the fruits have made them popular additives in many skin lotions and cosmetics.
  • Internally, concoctions have been used for dysentery, parasites and worms, malaria, diabetes, stomach disorders, pneumonia and as a laxative.
  • Bark decoctions are made into a pain-relieving mouth gargle, and is also said to treat dysentery, syphilis and gonorrhoea.
  • An infusion of the bark can be used to wash the head as a way of treating epilepsy.
  • Many of the traditional medicinal uses have not been fully investigated, and these should only be used as guidelines while further research is being conducted.

Practical

  • The baked fruits are used as a beer additive and are said to promote fermentation.
  • The seeds of ripe fruits are edible, and contain high amounts of energy, as well as significant amounts of phosphorous, protein, and lipids.
  • They are usually roasted before being consumed.
  • In turn, the seed oil is rich in oleic acid and essential fatty acids.
  • The boiled fruits are also used to produce a red dye, and the roots are reported to yield a bright yellow dye.
  • The wood is pale brown, light, not very hard, but quite tough, and is said to work well.
  • It is used as a good general-purpose timber and also to make shelves, fruit boxes, building materials, fence-posts and poles, hunting and fishing gear, musical instruments, carvings and smaller household items.
  • Sturdy dugout canoes have also been made from larger pieces.

Warnings

  • The fruits are reputed to be toxic- and should be avoided.
  • The trees have invasive root systems, can reach gigantic proportions, and bear exceptionally large and hard fruits, so care should be taken when choosing a position – do not plant near driveways, carparks, pools or other permanent structures that could be damaged by the expanding root system or falling fruits.

Wildlife

  • The heavily scented flowers open at night, and attract bats, who act as the main pollinators.
  • The flowers are naturally rich in nectar and will also lure a multitude of insect life – including moths, beetles, wasps and butterflies.
  • Nectar feeding bird species will flock to the flowers to get a taste of the sweet golden liquid, and the fallen fruits are readily devoured by monkeys, baboons, various bushbuck and on farms and game farms, livestock and game.
  • The fruits, both ripe and unripe, are said to be poisonous to humans, but are eaten by monkeys, baboons, bush pigs, porcupines and rhino.
  • The leaves contain essential amino acids as well as other minerals and nutrients including calcium, magnesium, and iron, and are browsed by elephants and kudu.

Advantages

  • The Sausage tree is perfectly suited for large gardens, parks, farms and reserves- where it will produce invaluable shade and food for a large number of animals.
  • It will also make a good, sturdy and decorative street side tree in warmer areas.
  • The trees can be planted next to river and stream banks, where they will help with future stabilisation.
  • In the garden, it is a most handsome shade giving tree, providing light, dappled shade throughout the year in warmer climates.
  • Planted in a rockery, they add vibrancy and colour, and they also make good boundary and hedge or screening plants.
  • Highly attractive when planted as an ornamental or accent feature, with decorative flowers and unusual fruits.
  • A fast grower in warm climates and provides food and shelter for a variety of wildlife.

Tolerance

  • The trees are tolerant of a wide range of external factors but are mostly suited for the warmer parts of the country, as the leaves are extremely sensitive to frost.
  • It can tolerate some cold, but not extreme and long-lasting frosts, and will survive in colder areas if adequately sheltered for at least the first 4-5 years.
  • It prefers areas with a relatively high annual rainfall, preferably no less than 500 mm, but established trees can endure the occasional, moderate, seasonal drought.
  • Older trees can withstand quite high temperatures. It is not suitable for very cold or dry areas.

Growth Rate

  • A relatively slow-growing tree; depending on the environment.
  • Under ideal, warm and moist conditions, it grows up to 1 m per year, but growth slows down in colder areas.
  • A good, sturdy, shaped-giving size may be reached within 5-6 years.

Lighting

  • Full sun.

Soil & Water

  • The trees will accept a wide range of soil types and have been found growing in very clay and rocky sols.
  • They prefer a well-drained, loamy, peaty and moist soil, with a slightly acidic to neutral ph.
  • Red clay and sandy soils will also be accepted.

Propagation

  • Readily and easily propagated from seed, wildlings or hardwood cuttings, the latter generally has a lower success rate.
  • Dry seeds store well under cool, airtight conditions, and viability can be maintained for at least 3 years.
  • Although pre-treatment is not essential, seeds may be soaked in hot or boiling water for 1 minute prior to sowing.
  • Sow the seeds in seedling trays filled with pure river sand, (preferably in the month of September), then cover them with a shallow layer of sand or compost, and keep moist, but not overly wet.
  • Store in a cool, bright and humid area. Germination typically commences within 10–25 days.
  • It is best grown in warm areas, due to cold intolerance