General Info – summary

This impressive deciduous Tree is usually up to 5m high.  Bark becomes dark brown and vertically fissured.  Roundish Leaves are simple, have stipules and 5-7 veins arise from the base.  Margins are entire toothed or scalloped.  Spectacular, usually white, 5-merous, regular, bisexual Flowers are in cymes with stamens and staminodes.  Fruit is a small wind dispersed capsule with papery petals and tiny seeds.

Description

Dombeya rotundifolia

Previous Names: Dombeya densiflora, Dombeya dinteri, Dombeya damarana, Dombeya multiflora, Xeropetalum rotundifolium.

SA Tree No. 471.

Common names: (Afr) Blombos, Blombossie, Blomhout, Blompeer, Dikbas, Dikbasa, Dralpeer, Drolpeer, Wildepeer.  (Eng) Blossom Tree, Common Wild Pear, Round Leaf Dombeya, Wild pear, Wild-pear, Wild Plum, Common Wild Pear.  (isiZulu) Inhliziyonkulu, Isiadlulambazo, Umbikanyaka, Unhliziyonkulu.  (Northern Sotho) Mohlaba-phala, Mokgoba.  (Setswana) Molobare.  (siSwati) Nhliziyo, Umbikanyaka (the tree that heralds the new season), Umwane.  (Tshivenda) Tshiluvhari.  (Xitsonga) Nishaphukuma Xiluvarhi.  This tree is not related to the pear tree – which in the genus Pyrus in the family Rosaceae.

Family: Malvaceae: (Wild Pear, Gossypium – cotton, baobab and Hibiscus family).  This family has about 240 genera and 4 200+ species.  Indigenous genera that have trees on this website includes Adansonia (baobab), Cola, Dombeya, Grewia, Hibiscus, Sparrmannia and Sterculia.  The usually alternate Leaves of all members possess stipules and apart from Adansonia, remain simple.  Flowers are regular, bisexual or unisexual and have 5 petals (Sparrmannia africana has 4).  Petals are absent in Cola and Sterculia.  There are 5 to many stamens with filaments often united into a staminal tube.  This surrounds the superior Ovary with its simple Style and capitate or lobed Stigma.  Fruits are usually nuts, schizocarps or loculicidal capsules.

Name Derivation: Dombeya after Joseph Dombeya (1742-1794) a French botanist who spent much time in South America.  His story is worth reading.  Part of his collection was stolen and is now in the British Museum.  There are more than 220 species in the genus Dombeya, 8 of which occur in southern Africa.  rotundifolia refers to the almost round leaves.

Conservation: National Status: L C. (Least Concern).  2008: V.L. Williams, D. Raimondo, N.R. Crouch, A.B. Cunningham, C.R. Scott-Shaw, M. Lötter and A.M. Ngwenya.

Tree

This Tree may reach 10m high but is usually up to 5m (photo 496).  It ends in a much-branched rounded crown.  When flowering together with the coral tree Erythrina lysistemon, their flowers usually signify the beginning of spring.  These trees either occur in clumps or are single.  The Trunk often has a single tilted stem (photo 496) and may reach 30cm in diameter.  The Tree may become multi-stemmed in dry areas.  The Bark becomes dark brown to black, rough, corky and fissured lengthwise (photo 40) – unlike Dombeya autumnalis, which has a smooth bark and smaller flowers that develop much later.  Raised light Lenticels (a usually raised corky oval or elongated area on the plant that allows the uncontrolled interchange of gases with the environment) are often visible on young trunks (photo 401).

Leaves

On this deciduous tree, the simple, spirally Leaves are almost circular to ovate and up to 20cm x 15cm.   Leaves may become larger on non-flowering stems and young leaves may be tinged with red (photo 50).  The thick, leathery leaves (photo 50) may be hairy on both sides.  Under the microscope, some of the hairs appear star-shaped.  The Upper surface is dark green and rough (photo 50).  The Lower surface is a paler green, has soft hairs and the Veins are more prominent (photo 303).  Small veins connecting the lateral veins are ladder-like (photo 52).  The Apex is rounded to broadly tapering.  The Base is cordate (lobed/heart shaped – photo 52) to round and has between 5 and 7 veins arising from it (photo 303).  The rolled under Margins range from irregularly toothed or scalloped to almost entire (with a continuous margin, not in any way indented).  The lateral veins tend to end within the scalloped margin (photo 52).  The Petiole (leaf stalk) with its stellate (star like) hairs is usually up to 4cm long.  Stipules (basal appendages of petiole) are narrow, have a triangular base and are fugacious (falling or withering away very early – photo 52).

Flowers

The spectacular white to pale pink (less common), sweet scented Flowers are up to 2cm in diameter and clustered at the ends of branches in Cymes (broad, more or less flat-topped, determinate flower cluster, with central flowers opening first – photo 83).  Each cyme is about 7+cm wide and less high.  The flowers usually emerge before the leaves and can be very impressive.  The Pedicels (stalks of single flowers) are hairy.  Below the flowers are 3 pubescent (hairy) floral Bracts which are caducous (an organ or part which is easily detached and shed early).  The flowers are bisexual and actinomorphic (Regular, symmetrical.  Flowers are vertically divisible into similar halves by more than 1 plane passing through the axis).  Prior to the buds opening, the 5 Sepals are hairy on the outside and may initially be red (photo 313).  They turn green and become reflexed once the bud begins to open (photo 399).  The 5 overlapping Petals are usually pure white but occasionally a light pink.  They are persistent and become papery after pollination, turning a clearly visible light brown colour (photo 116 under Fruit).  The numerous Stamens are of different lengths and each ends with an initially orange, oblong Anther that has parallel theca (pollen sacs – microsporangia of an anther.  They produce microspores – pollen grains in seed plants).  These anthers open through a longitudinal slit.  Linear, white-tipped, spatulate Staminodes (sterile stamens) arise with the stamens.  Each is up to 6mm long.  They are longer and thicker than the stamens and lack anthers (photo 35).  There is a single Pistil (a unit of the Gynoecium, the female element of the flower, composed of the Ovary, Style and Stigma).  The superior Ovary is up to 2,5mm wide and covered with densely matted woolly hair (photo 313).  2-8 Ovules occur in each locule.  The Style has 3 branches (photos 35 & 315).  (Jul-Nov).

Fruit

The tiny – about 6mm in diameter, almost spherical, silky haired, Fruit (photo 370) is a light hairy Capsule (a dry fruit resulting from the maturing of a compound ovary, which usually opens at maturity by one or more lines of dehiscence).  Flowers remain on the tree and the now brown persistent papery petals eventually act as wings (photo 370) to aid the wind dispersal of the completely ripe fruit.  In photo 371, the now ageing petal lobes are clearly visible.  The remains of the longitudinally dehiscent Anthers as well as the Stigmas and Styles are also visible.  The very small Seeds have a hard, rough Testa (seed coat) and are triangular in cross-section.  (Oct-Dec).

 

Distribution & Ecology

This Plant grows naturally in the bushveld, open woodlands, and in areas of a wide range of altitudes, moderate rainfall and is common on rocky hillsides.  The tree is both cold and fire resistant and may grow singly or in clumps.  It is Found in KwaZulu-Natal, Gauteng (common between Johannesburg e.g., Melville Koppies and Pretoria), Mpumalanga, North-west and Limpopo.  It is also located in Botswana, Swaziland, Namibia, Zimbabwe, Mozambique and northwards into East Africa.  Kudu browse the Leaves and young shoots.  At least 3 species of butterflies make use of the leaves e.g. the Ragged Skipper (Caprona pillaana) larva feed on the leaves.  They have a year-round flight period.  Green beetles (Melyris sp.) are also associated with this tree.  Many other insects are attracted including the scale insect (Lecanodiaspis tarsalis).  The flowers produces large quantities of Nectar, which is also utilised by honeybees.

Ethnobotany

This is a good bonsai plant.  The planted tree is often fast growing and may be spectacular when flowering.  It is one of the first trees to flower.  The blue-grey Wood is strong, fine textured and does not split.  It is widely used for implement handles, furniture, mine props and for carving.  Of this wood Galpin wrote, “A first-class timber, excellent for any purpose for which wood is required that does not split and has great strength.” The wood is termite resistant.  The Bark is strong and the inner bark makes good strong fibre that is used to make rope.  The trees are easily raised from Seeds and may grow up to 1,5m per year.  The Roots are not aggressive and this is a non-poisonous tree.  In places, the first spectacular spring blossoms form part of the ingredients used for aiding success in courtship.  The tree is widely used for local medicine.

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.

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.

Williams, V.L., Raimondo, D., Crouch, N.R., Cunningham, A.B., Scott-Shaw, C.R., Lötter, M. & Ngwenya, A.M. 2008. Dombeya rotundifolia (Hochst.) Planch. var. rotundifolia. National Assessment: Red List of South African Plants version 2020.1. Accessed on 2023/02/26.

 

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

http://www.plantzafrica.com/plantcd/dombeyrotund.htm

http://abcjournal.org/index.php/ABC/article/viewFile/1054/1005.

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