General Info

This impressive Tree may reach 21m high.  Short Spines are present.  Leaves are large and simple.  Small, monoecious, 5-merous flowers are in compact cymes.  Fruit is an ellipsoid berry with a single Seed.

Description

Bridelia micrantha, Bridelia stenocarpa.

RSA Tree No. 324.

Common names: Mitserie, Mitzeeri, Mitzeerie, Coastal Goldenleaf, bruinstinkhout, wild coffee.

Family Phyllanthaceae. In this diverse family Latex as well as Spines are usually absent.  This is diagnostic and excludes them from Euphorbiaceae.  There are about 50+ genera and 2 000 species in this family.  They are most numerous in the tropics and most members are trees.  Leaves are usually simple, alternate and petiolate.  Leaf margins are usually entire and leaves are present in most species.  The actinomorphic Flowers are usually unisexual and are monoecious or dioecious.  The superior Ovary has 2 ovules in each locule.  The Fruit is a berry, drupe or schizocarp.  Local genera containing trees include Antidesma, Bridelia, Cleistanthus and Heywoodia.

Name derivation: Bridelia – named after Samuel Elisee de Bridel (1761-1828) – a Swiss-German moss specialist.  micrantha: Greek – small flowered.  There are 4 species of this genus in southern Africa.

Conservation Status: L C. (Least Concern).  2009 (Raimondo et al.).

Tree

This fast growing, deciduous Tree is frost resistant.  It may reach up to 21m in height with a spreading, fairly open crown.  It is common in high rainfall areas.  In the open, away from tall competition, the rounded crown is spreading.  Bark is brown/grey and rather flaky in younger specimens.  It becomes rough and cracking almost into squares in older specimens.  Short, blunt Spines occur on younger branches and may remain on the main trunk (photo 617).  Branches are hairy only when young and have many raised dark lenticels (a usually raised corky oval or elongated area on the plant that allows the uncontrolled interchange of gases with the environment).  Branches may also have white patches.  The young branches are green to brown and hairy (photo 187).

Leaves

The semi deciduous tree has simple Leaves that are elliptic to obovate and large – up to 28 x 12cm.  They are dark shiny green above but lighter, usually smooth and may have some hairs below.  The alternatively arranged leaves are in the same plane (photo 621).  Young leaves are often purplish to reddish and, prior to falling, the mature leaves often develop a spectacular bright red or gold colour (photo 341).  The Blade has up to 15 pairs of often-yellowish lateral Veins.  Most of them run up to the margin without branching – forming a herringbone pattern.  They spread towards the apex in the process.  These veins protrude slightly below and all veins may be clearly seen against a strong light (see photo 622).  The Apex is tapering, bluntly or sharply pointed or acuminate (an acute apex whose sides are somewhat concave and taper to a protracted point).  A drip-tip may be present.  The Base is broadly tapering to rounded.  The Margin is entire (with a continuous margin, not in any way indented but may be hairy) and may be wavy or may appear to be scalloped.  The Petiole (leaf stalk) is up to 1,3cm long, thickset and hairy – at least when young.  Small green Stipules (basal appendages of the petiole) are visible but soon fall off (photo 71).

 

Flowers

The very inconspicuous small (up to 3mm in diameter) Flowers are located in clusters in leaf axils.  They are in compact Cymes (broad, more or less flat-topped, determinate flower clusters, with central flowers opening first).  Flowers are unisexual and monoecious (separate male and female flowers on the same plant).  The Male Flowers have a short Pedicel (stalk of a single flower in a cluster), which is absent in female flowers.  The 5 triangular Sepals are usually small.  Petals are smaller than the sepals and obovate (the terminal half is broader than the basal).  The 5 Stamens have basally joined filaments and a rudimentary ovary is present. In the Female Flowers, the disc (fleshy or elevated development of the receptacle) is double and surrounds the base of the ovary.  This superior Ovary usually has 2 locules with 2 ovules in each.  Flowers are best viewed with a hand lens.  (Oct-Apr).

Fruit

The Fruit is a small ellipsoid Berry (pulpy, indehiscent fruit like a grape or tomato), which may reach 10 x 7mm.  The fruiting branch is distinctive and the fruit change from green to blackish when mature.  Each fleshy berry is sweet, edible and, by abortion, contains only a single Seed.  The remnants of the Calyx are visible for some time (photo 416).  Seeds have copious albumen (starchy or other nutritive material surrounding the embryo).  (Nov-Apr).  Some years no fruit is produced.

Distribution & Ecology

This tree is not drought resistant but is tolerant of light frost.  It is common in open savannah, fringes of forests, swampy ground, along rivers, streams and in riverine woodlands.  These trees are common up to an altitude of 1 750m.  They are found in Eastern Cape, KwaZulu-Natal coast, Limpopo, Mpumalanga, Zimbabwe e.g. at the ruins, Zambia and into Tropical Africa including Angola, Ethiopia, Senegal and Uganda.  It is also located on Reunion.  Felled trees produce many shoots.  The Flowers attract bees and wasps.  The Paradise skipper butterfly (Abantis paradise) fly for most of the year but are more frequently seen from April to June.  Their larvae feed on the Leaves as do the larvae of the Giant Emperor (Charaxes eastor).  Here the adult males have a wingspan of 8,5cm.  Another example is Parosmodes morantii – found from KwaZulu-Natal northwards into tropical Africa and commonly seen from (Dec-Apr).  The Silk moth: Anaphe panda larvae also feed on the leaves and are used in silk production.  Nyala, bushbuck and grey duiker also consume leaves.  Black rhino eat the Bark and leaves.  Fruit attracts many birds e.g. green pigeons, starlings, bulbuls, doves and louries. Narina Trogon, a green backed bird, also visits this tree.

Ethnobotany

The attractive dark brown heart Wood and the lighter sapwood are durable and termite resistant and competes with stinkwood for quality furniture wood.  It has a medium density, saws easily, holds nails, screws, and is reasonably resistant to fungi and most insect attacks.  However, the Lyctus beetles can be attacked the wood.  The wood is used for flooring, furniture making, panelling, fence poles and mine props.  It also makes good firewood and charcoal.  This forms a good decorative garden shade tree, which can withstand temperatures as low as – 4°C.  Propagation is by seeds and growth is up to 2m per year.  The Seeds have a short viability and do not store.  Fruit pulp has a growth inhibitor and must be removed before attempting to germinate the seeds.  Resin from the tree is used for sealing cracks e.g. in doors.  Leaves are fed to cattle.  It has been planted to stabilize irrigational canals and to decrease waterlogging in soils.  Black dye is extractable from the leaves and red dye from the Bark.  Extracted bark tannins have some anti-bacterial action.  Some anti-inflammatory effects have also been found.

References

Boon, R. 2010. Pooley’s Trees of eastern South Africa. Flora and Fauna Publications Trust, Durban.

Burrows, J.E., Burrows, S.M., Lotter, M.C. & Schmidt, E. 2018. Trees and Shrubs Mozambique.  Publishing Print Matters (Pty) Ltd.  Noordhoek, Cape Town. 2018.

Coates Palgrave, M. 2002. Keith Coates Palgrave Trees of Southern Africa, edn 3. Struik, Cape Town.

Ginn P.J. Mcilleron W.G. and Milstein P. le S, 1989. The Complete Book of Southern African Birds. Struik, Cape Town.

Palmer, E. & Pitman, N. 1972. Trees of southern Africa, Balkema, Amsterdam, Cape Town.

Schmidt, S. Lotter, M. & McCleland, W. 2002. Trees and Shrubs of Mpumalanga and the Kruger National Park.

van Wyk, B. & van Wyk, P. 1997 Field guide to Trees of Southern Africa, Struik, Cape Town.

http://worldagroforestry.org/treedb2/speciesprofile.php?Spid=374

http://www.plantzafrica.com/templates/voteplant.php

https://en.wikipedia.org/wiki/Bridelia_micrantha

http://uses.plantnet-project.org/en/Bridelia_micrantha_(PROTA)

https://www.researchgate.net/publication/242519528_Type_material_in_the_moss_herbarium_of_Samuel_Elisee_von_Bridel_1

http://posa.sanbi.org/flora/browse.php?src=SP

https://www.hindawi.com/journals/ijfr/2012/186549/