Combretum erythrophyllum

River Bushwillow (E)
Riviervaderlandswilg (A)
Rooiblaar (A)
Rooiblad (A)
umhlalavane (Z)
umdubu (X)
muvuvhu (V)

Description

A highly decorative, small to medium sized, single or multi-stemmed, densely foliated tree, with a beautifully mottled, pastel grey bole and glossy, almost lance-shaped leaves that turn beautiful shades of russet gold and purple in autumn. The trunk is often quite short, branching and curving low down, giving the tree a drooping, tortuous appearance. Masses of creamy, puffball like flowers appear shortly after the flush of fresh spring leaves, followed shortly by striking and unusual, winged fruits that remain on the tree for many months. Its lovely shape, beautiful bark and its constantly changing foliage makes this stately tree a most worthwhile garden subject.

SA Tree

Family

Combretaceae (The Bushwillow or White Mangrove family)
A family of flowering plants belonging to the order Myrtales, comprising of trees, shrubs and lianas, with somewhat 600 species and 20 genera, occurring mostly in tropical and subtropical parts of the world. Only three species are known to frequent mangrove-like, muddy habitats or estuaries. Members can be characterised by leaves that are simple, alternately or oppositely arranged, often with prominent venation, and stipules that are absent or reduced. The flowers are mostly bisexual, less often unisexual, and radially symmetric. Fruits are generally a flattened, ribbed or winged drupe, with a single seed, although there are exceptions.

Habitat

Most often found along permanent river and stream banks and in riverine forests and associated bush clumps, where it tends to form thick stands.
The typically multi-stemmed trunks can often be seen reclining towards and overhanging the water due to the annual torrential flooding.
Away from watercourses, where the water table is high enough, it can sometimes be found in open woodland, bushveld and grassland.
Found from the coast to elevations of about 1500 m, in northern Natal, Transkei, Orange Free State, Northern Cape, Gauteng and North West areas, extending into Swaziland and Zimbabwe.

Bark

Usually a smooth, pale grey or yellow to orange-brown on young trees, becoming darker as the tree matures.
With age, the bark tends to flake in patches to reveal a pale grey under surface and sometimes large lumps, giving the tree a mottled appearance.
The stems may later scale into parts, leaving dark brown spots behind, and often, insects eat into the young twigs, especially during the autumn months, causing them to die and break off.
Giant slits can sometimes be observed on the bark of very large trees.
The main stem is single and erect, or multi-stemmed from the base, with a dimmer of 400-600 mm.

Foliage

Deciduous.

Simple, typically opposite, or sub-opposite, elliptic to oblong-elliptic (50-100 x 15-40 mm), sharp tipped leaves, carried on short, lateral twigs.
Less often, the leaves may be alternate or in 3-wholrled clusters.
Young leaves are yellowish-green on both surfaces, glossy and fibrous.
A flush of fresh, whitish, inflorescence-like leaves can often be observed in spring, and these tend to drop as the flowers develop.
As the leaves mature, they become a fresh, light to dull, medium green.
Mature leaves are usually only very finely hairy or hairless above, with 6-10 pairs of conspicuous, indented, forward sweeping lateral veins, and a thinly leathery texture.
The undersides are yellowish-green, finely velvety, and the margins are entire and very finely hair fringed.
The leafstalk is 1-4 mm long. In autumn, the leaves turn a beautiful, yellowish russet-red.

Flowers

Dense spikes of inconspicuous, creamy to pale yellowish-green, semi-spherical, puff-ball like flowers (8-12 x 10 mm), carried in the axils of the leaves.
The flowers tend to appear shortly before or after the first new leaves and are wonderfully fragrant. (September- November).

Fruit

4-winged, greenish brown when young, ripening to a yellowish, honey-brown.
The fruits are usually 1-1.5 cm long and have well-developed apical pegs.
They tend to remain on the tree until the next flowering season. (January- October).

Height

5-13 m

Spread

4-10 m

Medicinal

The leaves of this tree have been recorded as containing several triterpenoids, as well as flavonoids and polyphenols.
Extracts of the bark and leaves have shown numerous antibacterial, antifungal, anti-inflammatory and antioxidant activities.
Combretastatin A-4 disodium phosphate, a compound found in several Combretum species, is said to show strong tumour-inhibiting properties, and is currently undergoing further clinical studies.
Concoctions of various parts are used to treat pain, coughs, infertility, stomach disorders, venereal disease and are also taken as purgatives.
Pieces of bark are infused with water and either taken internally or applied topically to treat festering sores and wounds.
The dried and powdered gum can also be applied to sores.

Practical

The wood is coarse grained, tough and works well, with an even yellow-brown colouring.
It is popular as a general-purpose timber, and has been used in the construction of buildings, furniture, ornaments, troughs, smaller household utensils and grain mortars.
It makes an average quality firewood.
A rich, dark brown dye can be extracted from the roots, and this is used for tanning purposes.
Damaged stems exude a sticky, elastic gum that can be used as a non-cracking varnish.
The dried fruits are often used in floral arrangements.

Warnings

There are reports of the seeds being used as a de-worming remedy, but care should be taken as they are poisonous and are known to cause severe hiccups.
The roots have been used medicinally but are regarded as poisonous.

Wildlife

The flowers will lure many butterfly species, and it is also the larval host plant for several species, including the Hairtails, Policeman’s and the Orange-barred Playboy.
Bees, wasps, beetles and more will also be attracted.
Wasps lay their eggs in the fruits, and these attract several species of insectivorous birds.
A select few seed-eating birds may also be attracted, and the trees are popular nesting sites.
The leaves are occasionally browsed by elephants and giraffes, as well as larger antelope.

Advantages

With its range of beautiful seasonal colours, it is the ideal tree to add colour and vibrancy to gardens all year round.
It makes a lovely single specimen or focal tree and will do well in very wet areas where other plants might struggle.
It does not have an aggressive root system, so it can be planted close to paving and driveways or pools and other permeants structures without fear.
It provides lovely shade, and has a generally hardy nature, making it idea for street side planting, and it will do well even in cold Highveld gardens.
Planted on a large, open lawn or in a park, it is sure to attract attention.
The trees make good, sturdy natural windbreaks and screens, and can be trimmed down to form a beautiful hedge.

Tolerance

Lauded as one of the most responsive and adaptable of the Bushwillow species, it tolerates a good amount of climatic and soil variations.
It is remarkably tolerant of frosts, but only after 2-3 winters.
Unestablished plants should be adequately sheltered for at least 2-3 years.
The tree can resist and endure the occasional drought, but while it is establishing itself, (first 3-4 years), it should be watered regularly as to not hamper development.
It tolerates a wide range of very different soil types, even poor and stony soils.

Growth Rate

Moderate to fast, 600-1200 mm per year under ideal conditions.
(A height of 6 m can sometimes be achieved in less than 4 years).

Lighting

Full sun or light, partial shade.

Soil & Water

A wide range of soil types will be accepted, ranging from heavy, dark loam and alluvium, more clayish soils to sandy and rocky, granite types, with a neutral ph.
It has moderate to high water requirements, especially during the developing years.
Water at least once or twice per week.

Propagation

Very easily propagated from fresh, unparasitized seeds.
Soak the seeds in water overnight to help soften the outer coatings and aid germination.
Sow in a well-drained, fertile mixture of river sand and compost (2:1), and place in a bright, temperate area.
Mist the soil often, making sure it stays moist but not overly wet.
Germination is rapid, and usually occurs within 2-3 weeks.