Trichilia dregeana

Trees

BOTANICAL: Trichilia dregeana
COMMON NAME: Forest Natal Mahogany / Natal Mahogany / White Mahogany /cape Mahogany / Thunder tree / Red Ash
OTHER NAMES: Bosrooiessenhout / basteressenhout / rooiessenhout (Afr); uMathunzini (Zulu); umKhuhlu (Xhosa)
SA TREE NO: 300

FAMILY: Meliceae (Mahogany family)

A Family of flowering plants, belonging to the group order Sapindales, containing somewhat 51 genera and 575 species of mostly trees, with a few shrubs and rarely, mangroves and a select few herbaceous plants. Members occur mostly in tropical and subtropical zones, but the family has a wide, pantropical distribution, with species being recorded in China and Australia. Characteristics include large, often compound leaves, dense, branched inflorescence, and fruit that are either in a leathery capsule form or are brightly coloured. This family is considered to be of economic importance, not only for its timber trees, but because many members produce either edible fruits or medicinal oils and resins.

BASIC OVERVIEW

One of our most valuable and handsome indigenous trees, important not only for its ornamental qualities, but also as a source of food and medicine. The Natal Mahogany is an impressive, medium to tall, evergreen tree, with a relatively short trunk, a large, rounded or dome shaped crown of densely arranged, lustrous, dark -green leaves that make a magnificent canopy, and highly decorative, edible fruits.

  • HABITAT: The tree favours high-rainfall areas, with mild winters. Natural growth is somewhat restricted to coastal, evergreen or montane forests, or in the transition zones between forest-savannah and wet, slightly humid, evergreen forest, and the trees can be found especially along the eastern coastline of SA, extending into tropical Africa.
  • DECIDUOUS/EVERGREEN: Evergreen
  • BARK: Smooth and pale grey. On older specimens, the bark often becomes slightly rougher and segmented, creating a somewhat buttressed appearance. The bole of the tree has a distinctive, cylindrical shape, and can reach 120 – 200 mm in diameter.
  • FOLIAGE: The dark green, glossy leaves are arranged in a compound manner, with 3-4 pairs of alternate or opposite leaves plus a large terminal carried on long, somewhat hairy petioles. The lower surface of the leaf is paler, frequently hairless, or with a few, miniscule hairs arranged along the veins, which are set apart widely and occur in pairs of 7-12. The large leaves are broadly oval to oblanceolate, with entire, often wavy, margins, and typically measure at 12.5-21 x 5.5-8.5 cm. The petiole (leafstalk) is 8-10 cm long.
  • FLOWERS: The cream-white flowers are carried in short, densely packed flowerheads or sprays, up to 5cm in length, from October to November. The petals are quite large, up to 2.5 cm long, and are fused into tubes by the stamens (male fertilizing structure of a flower, classically consisting of a pollen-containing anther and a filament). The petals often have a velvety texture, and male and female flowers are carried on separate trees.
  • FRUIT: Very pretty, creamy-brown, green or off-purple capsule, 30-50 mm in diameter, splitting into 3 to 4 valves to reveal brightly coloured seeds. The fruit generally grow directly from the leafstalk, but are sometimes carried on a short petiole of up to 3mm.
  • SEED: Glossy black seeds, often almost completely covered by the bright-red or crimson remains of the aril. Very decorative, up to 6 seeds per fruit. (January to May)

LANDSCAPING DETAILS

  • HEIGHT: 10 – 40 m (usually less on open spaces or in cultivation)
  • SPREAD: 4 -30 m.
  • TOLERANCE: Trichilia is sensitive to frost, especially when young or newly transplanted, and undeveloped trees should be protected from extreme cold for the first 2-3 years. Luckily, if the injury is not too severe, the tree can recover well from frost damages. Very tolerant of fire, but only tolerant of mild, short periods of drought.
  • GROWTH RATE: Young trees are reasonably fast growing, , with an annual girth increase of just over 20cm. As the tree matures, growth lessens slightly, but it is generally a fast grower.
  • LIGHTING REQUIREMENTS: Full sun or semi to deep shade is tolerated. Very adaptable.
  • SOIL AND WATER REQUIREMENTS: Clay or loamy soil. Optimum growth usually occurs in rich, fertile, moist soils, with a slightly alkaline Ph.
  • ADVANTAGES: A wonderfully attractive, large and fast-growing tree that provides splendid, deep shade all year long, and lures a vast amount of wildlife. It is ideally suited for large gardens and parks, and is arguably one of the best trees for lining streets and avenues. Many farmers plant the tree in their plantations due to its vast shade giving abilities It can tolerate high or low light environments, and due to this versatility, it is also gaining popularity as a patio or indoor pant. It also takes well to pruning, and can be easily trained to form a hedge, windbreak or screen.
  • WARNINGS: The bark is extremely toxic, and has been used as an effective fish poison. The seed coat is also known to be contain certain toxins, and should be removed before using the seeds. Only a well-prepared seed-oil should be used, and care must be taken, especially if used internally.
  • WILDLIFE: The dense foliage is popular amongst many bird species as a nesting site, and the fleshy seeds also lure a myriad of seed-eating birds and honeybees. Baboons have been known to eat the seeds, and several butterfly species, especially the stunning Charaxes, use it as a breeding tree.
  • PROPAGATION: Most often propagated from seeds, which should ideally be sown when fresh, as they lose validity upon drying. Plant in a well-drained mixture of equal parts compost and river sand, and place in a bright, warm and moist area. Water often, but allow sufficient time for the soil to dry out to prevent damp and mildew setting in. Germination should occur within a month, and the seedling grow fast, reaching nearly half a metre within the first year.
  • MEDICINAL: A highly medicinal tree. Bark decoctions are primarily used as enemas, (one teaspoon of bark, crushed, and mixed with one cup milk) to treat stomach disorders, kidney infections and subsequent backaches, and are also applied topically to treat scabies. The leaves are boiled, and the liquid is then used to bathe bruises. Poultices are also made from them, and is said to bring relief from eczema. The seed oil is said to speed up recovery of fractured limbs and wounds, and is also used as a massage oil to treat rheumatism. A large quantity of limonoids have been isolated from the seeds, and these have anti-fungal and anti-inflammatory properties. The bark, which is very toxic, does however contains certain elements which could play a role in lessening inflammation and suppressing pain.
  • PRACTICAL: The pale brown to pink wood is soft, evenly-grained and works well, hence its popularity for carvings, especially in the tourist market. Various household items, such a bowls and spoons, as well as furniture and shelving are made from it. It polishes very well, but should be adequately treated to prevent borer attacks, and is not very durable. The scarlet seed arils (superfluous seed covering, typically coloured and hairy or fleshy) can be cooked and eaten as a vegetable, or crushed to extract a milky juice, which can be drunk or used as a food improver. The seeds, apart from being eaten, contain a high-quality oil, which can be used in cooking processes, or as an additive to make excellent soap, cosmetics and even candles.
  • ADDITIONAL FACTS: Trees growing in open, sunny places may start bearing fruit at about 10 years of age, whereas those in more shaded, sheltered conditions may not fruit before they are at least 20 years old.