Diospyros lycioides subsp. guerkei

General Info – summary

This shortish Tree has a smooth bark and may also be a shrub.  Milky sap & thorns are absent.  The spirally arranged, leathery, hairy Leaves are simple & rest on a short petiole.  The solitary creamy white to yellow actinomorphic and 5-merous Flowers are functionally unisexual.  Male flowers have 10 stamens & females have 5 styles.  Fruit is a berry with a persistent accrescent calyx.  Up to 6 smooth seeds are produced.

Description

Previous Names: Royena guerkei, Royena lycioides subsp. guerkie.

SA Tree No. 605.2.

Common names: subsp. guerkei.  (Afr) Bessieboom, Bloubos, Hoeveldbloubos, Jakkalsbessie.  (Eng) Bluebush Quilted Bluebush, Transvaal Bluebush.  (isiZulu) Umnqandane.  (Northern Sotho) Motloumana.  (siSwati) Mcafutane, Umcafudane.  (Tshivenda) Muthala.

Family Ebenaceae (persimmon and ebony family).  The family has some plants known for their useful wood and others for fruit.  Trees are usually located in tropical and warmer temperate regions.  There are more than 750 species, in 4 genera, worldwide and the 37 species in South Africa occur in 2 genera (Euclea and Diospyros).  The bark and heartwood are black.  The simple, coriaceous and entire Leaves lack stipules and are usually alternate or may be opposite, but both may occur on the same plant.  The usually unisexual and regular Flowers have a persistent calyx that is often divided near to the base.  The corolla usually has a short tube, with Petals fused at the base and extending into overlapping lobes.  The basifixed anthers are longer than the filaments.  The superior ovary has up to 2 ovules in each locule.  The styles may have 2-5 branches.  Fruit is a berry with an accrescent calyx, which may dehisce slowly.  Young fruit contains tannins and is usually avoided by animals until ripe.

Name derivation: Diospyros: Dios – divine; pyros – pear (referring to the flavour of some fruits).  lycioides referring to the likeness of a member of the potato family: Salonaceae. subsp. guerkei – in honour of R.L.A.M Gurke or Max Gurke: German botanist (1854-1911).    

Name derivation: Diospyros: Dios – divine; pyros – pear (referring to the flavour of some fruits).  lycioides referring to the likeness of a member of the potato family: Salonaceae. subsp. guerkei – in honour of R.L.A.M Gurke or Max Gurke: German botanist (1854-1911).

Name derivation: Diospyros: Dios – divine; pyros – pear (referring to the flavour of some fruits).  lycioides referring to the likeness of a member of the potato family: Salonaceae. subsp. guerkei – in honour of R.L.A.M Gurke or Max Gurke: German botanist (1854-1911).    

There are in excess of 700 species in the genus Diospyros worldwide.  These species are tropical and subtropical and usually dioecious (unisexual floral structures with male and female parts are on separate plants).  The valued timber plants are called ebony trees and produce dense, hard and dark timber.  Trees valued for their fruit are called persimmon trees.  Neither ebony nor persimmon plants are indigenous in South Africa.  Here there are about 18 species and subspecies of the genus Diospyros.

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

Tree

The main Stem (or trunk is main axis of the plant, the leaf and flower bearing as distinguished from the root-bearing axis) is usually multi stemmed (photo 180) but may be single stemmed.  The Tree is densely branched with a dense crown and is usually 1-4m high but may reach 7m).  The dark grey Bark is relatively smooth (photo 209).  Light to dark grey Branches tend to grow upright.  Young stems are often hairy (photo 347 – under Leaves).  No milky sap or thorns are present.

Leaves

The smallish, leathery, blue-green or dull grey-green and spirally arranged Leaves (photo 347) are crowded at the ends of short branches.  Leaves may reach 8 x 2,5cm but are usually smaller and are simple (have a single blade, which may have incisions that are not deep enough to divide the blade into leaflets – photo 208).  Depending on the weather, the plant may be deciduous.  Leaves are elliptic, obovate (upside-down egg-shaped) or oblanceolate (the leaf is broader at the apical third than at the middle) and tapers towards the base.  They may be hairy especially below and over the Veins.  The amount of hair decreases with time.  The Midrib has 5-6 pairs of lateral veins, which are visible and often prominent (photo 208).  Here the Apex is broadly tapering to rounded.  The tapering Base may be asymmetric (not equal to the opposite side – photo 344) and is partly rolled under.  The Margin and young leaves are hairy – at least when young (photo 590), and entire (with a continuous margin, not in any way indented – photo 344).  The distinct but usually short Petiole (leaf stalk) is 3 to 15mm long.  Leaf veins are distinctly raised net veined below, and all veins are sunken above (photo 208).  The distinctive patterned net veining is best observed when the leaf is held against a strong light (photo 590).  From this vantage point, the hairs on the margin are visible.  In the field, a hand lens would help.

Flowers

The pendulous, solitary, bell shaped, creamy white to yellow dioecious Flowers are functionally unisexual floral structures with critical male and female parts in separate plants.  They develop in leaf axils.  Individual flowers are small, up to 15mm in diameter and 8mm long.  The sweetly scented flowers – especially at night are actinomorphic (Regular, symmetrical.  Flowers are vertically divisible into similar halves by more than 1 plane passing through the axis).  Each flower is supported by a hairy, relatively long Pedicle (stalk of a single flower) which may reach 3cm long (photo 283).  The hairy Calyx has 5 thin, conspicuous, long, deeply divided Sepals which are persistent and become partly reflexed (photo 283).  The Corolla is up to 1cm long.  It has a swollen middle, narrowing apex, is urn-shaped (photo 581), and contains 5 Petals with united bases.  The throat is widely opened, and the petal lobes overlap and reflex as they open (photo 284).  In the Male flowers, there are 10 Stamens, each about 4mm long.  The Filaments are shorter than the basifixed Anthers.  There is a short Style, which lacks a stigma.  The Female flowers (photo 585) have a single Pistil (a unit of the Gynoecium, the female element of the flower, composed of the Ovary, Style and Stigma) situated on a hairless Disc (a more or less fleshy or elevated development of the receptacle).  In photo 585, the infertile male parts with bristle covered Staminodes (sterile stamens) are visible.  Here the Ovary is superior (one that is free from the calyx or perianth) and has 5 styles each ending in a stigma.  (Aug-Dec).

Fruit

The soft and hairy young Fruit is a Berry (pulpy, indehiscent fruit like a grape or tomato) with a jelly like flesh.  It is almost spherical or oval in outline and up to 2cm long.  It is initially green (photo 25) turns rosy (pinkish) or attractive bright red (photo 659), then light brown to black and hard when mature (photo 317).  During this process, all hairs are lost.  The fruit closely resemble a miniature persimmon.  The 5 persistent deeply divided Calyx lobes are initially green and become accrescent (continue to grow after flowering and becomes large and conspicuous – photo 25).  They become folded back, and each fruit is eventually up to 1,5cm long (photo 25).  A persistent pointed style may be visible on the young fruit (photo 700).  The mature fruit dehisces slowly, and old fruit may remain on the tree until at least the next flowering season.  Up to 6 smooth brown Seeds are produced.  Each is up to 1,3cm long, and a nearly straight-line groove is present (photo 700).  (Jan–May).

Distribution & Ecology

The distribution of subsp. guerkei is very wide.  It is common in grassland, forest margins and are often pioneer plant (hardy species which are the first to colonize new or previously disturbed areas).  They are found in rocky habitats and often associated with outcrops of Quartzite (rock composed almost entirely of quartz.  Quartz is non-foliated and usually forms from the metamorphosis of sandstone).  These plants usually occur to the North of the Vaal River.  In SA, the plant is found in Gauteng e.g., Melville Koppies Nature Reserve where over 40 indigenous trees can be seen), KwaZulu-Natal, Limpopo, Mpumalanga, and North West.  Beyond SA, it occurs in Swaziland and Mozambique.  The Fruit is consumed by antelope, dassies and many birds.  Bees are involved in pollination.  The larvae of the Mooi River Opal butterfly (Chrysoritis lycegenes) feed on the Leaves and those of Myrsine africana as well as Searsia spp.  The leaves may be mildly poisonous at times.  The Flowers attract many insects, including bees and, consequently, many birds.  Birds also consume the ripe Fruit and assist with seed dispersal.  Rock dassies or rock hyrax (Procavia capensis – the closest living relative to the African elephant despite being rabbit sized), monkeys and Pied Starlings also consume the fruit.  The fruit contains tannins and is usually avoided by animals until the fruit is ripe and the tannin level decrease.  Tannins are astringent (shrinks or constricts body fluid) and decrease animal consumption.

There are four subspecies of D. lycioides, which differ mainly in leaf appearance and distribution:

Ethnobotany

The Wood is strong but relatively thin.  Heartwood is brownish pink and sapwood is lighter.  The wood sands and polishes well.  It has been used to make spoons, build huts and for fuel.  Tough black Roots can cause problems with ploughs.  Roots and twigs are used as toothbrushes.  They contain antibacterial compounds against oral pathogens.  Roots are very strong and can cause problems with ploughs.  They also provide a yellowish dye.  The flowers attract bees, and the resulting honey is excellent.  Ground seeds have been used as a substitute for coffee.  Ripe Fruits are edible and sweet tasting.  However, a report suggests that the fruit may be slightly poisonous.  Fruit can be used to make alcoholic drinks – including beer.  Planted trees will attract birds.  To obtain fruit, both male and female trees must be planted – preferably in full sun.  These can be obtained from cuttings from male and female trees.  Water the young plants regularly.  This wind and cold hardy trees are also used for Bonsai.  Trees take 4 or more years to flower.

Other subspecies

Apart from Diospyros lycioides subsp. guerkei, there are three other subspecies, which differ mainly in leaf appearance, hairiness and plant location.

Subsp. lycioides.  It is usually a shrub or small bushy shade tree op to 4,5m high and is more numerous in drier areas.  Leaves are up to 4 x 1,5cm, smooth or slightly velvety and lateral veins are not raised.  Leaf base may be blue-green.  Location is widespread within the summer rainfall region thus excluding the Western Cape.

Subsp. nitens has smaller leaves (up to 2 x 1cm) covered with dense, silvery hairs on both sides.  Location is in grasslands and rocky outcrops from Polokwane (Pietersburg) in Limpopo, southwards to western KwaZulu-Natal and then northwards.

Subsp. sericea.  The younger Leaves are usually densely covered with silky hairs.  On the lower leaf surface of larger leaves, the midrib is raised but, but the lateral veins are only slightly raised.  Leaves are usually bigger (up to 8 x 3cm) than subsp. lycioides.  Location is mainly subtropical and includes the eastern parts of South Africa from the Eastern Cape to Mpumalanga.

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.

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

Foden, W. & Potter, L. 2005. Diospyros lycioides Desf. subsp. guerkei (Kuntze) De Winter. National Assessment: Red List of South African Plants version . Accessed on 2024/12/26.

Lawrence, G. H. M, 1951. Taxonomy of Vascular Plants, The Macmillan Company, New York. Tenth Printing 1965.

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://www.plantzafrica.com/plantcd/diospyroslyc.htm

http://witkoppenwildflower.co.za/diospyros-lycioides-subsp-guerkei/

https://scholar.sun.ac.za/handle/10019.1/72654

http://www.prota4u.org/protav8.asp?p=Diospyros+lycioides good.

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

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