Information on selected trees

ALL THE WAY FROM THE SWAMPS OF SOUTH-EASTERN USA

Taxodium distichum  (Swamp cypress, Moerassipres)

Taxodium distichum is a conifer that grows naturally in the saturated and seasonally inundated soils of the south-eastern parts of North America. It is a large tree reaching 25 – 40 m, with a trunk diameter of 2 – 3 m. The tallest known individual specimen grows in Virginia and is more than 44 m tall, while the oldest specimen in North Carolina is more than 1600 years old, making this one of the oldest living plants in eastern North America.  The swamp cypress has been chosen as the national tree of the State of Louisiana.

For a short period in late autumn the leaves of the swamp cypress are a lovely, rusty red.

Unlike most other species in the family Cupressaceae, the swamp cypress is deciduous, losing its leaves in winter, hence the common name bald cypress. In their natural swamp habitat many T. distichum trees have so-called knees growing around the main trunk. These woody projections are usually above the normal water level.  Their function is not entirely clear, though it is likely that they support the tree and stabilise it in the flooded or flood-prone areas where the trees naturally grow.  The De Waal Park specimens do not have knees.

 

The swamp cypress is monoecious, with separate male and female flowers on the same tree. The male catkins are about 2 mm in diameter and are borne in slender, drooping clusters. The small female cones are found singly or in clusters of two or three. The bark of the tree is gray-brown to red-brown, shallowly vertically fissured, with a stringy texture.

The typical bark of the swamp cypress with its grey-brown colour and stringy texture.

This species is a popular ornamental tree, grown for its light, feathery foliage and orange-brown to dull red colour in autumn.  Cultivation is successful far to the north of its native range and it is also commonly planted in Europe, Asia and elsewhere in temperate to subtropical climate zones. It does, however, require hot summers for good growth.

There are more than a dozen swamp cypresses in De Waal Park, most of them growing well in the heavy clay soil that becomes heavily water-logged in winter. One of the largest specimens, in the central part of the park above the fountain, provides shade to a long wooden table and benches.

 

THREE PHOENIX PALMS

Phoenix is a genus 14 palm species that occur over an area as far west as the Canary Islands, across Africa as far south as Namibia and South Africa, northwards to the extreme south-east of Europe (Crete), and across southern Asia from Turkey to southern China and Malaysia in the east.

Most Phoenix species occur in semi-arid regions, usually where the groundwater levels are high and near rivers or springs. All Phoenix palms have pinnate rather than palmate leaves. Typically there are sharp spines on the basal portion of the fronds – these are leaflets which have changed, taking on a protective function. Palms across the Phoenix genus readily hybridise with one another resulting in naturally occurring variations. This makes identification problematic and in De Waal Park there is at least one unidentified Phoenix palm.  Trees from the Phoenix genus often host other plants on their stems, and this is also the case in the park.  

SA22 Phoenix reclinata (Wild date palm, Wildedadelboom)

Phoenix reclinata 

This palm is native to tropical Africa, Madagascar, the Comoro Islands and occurs naturally as far south as the Eastern Cape, hence its South African tree number.  P. reclinata can tolerate salt-spray and moderate drought where the water table is permanently high, as is the case in De Waal Park, where there are 12 specimens.

Phoenix reclinata fruit

The wild date palm mostly grows in clumps with multiple stems and its name refers to its reclining growth habit. The stems can reach a height up to 15 m and the foliage can grow to 4.5 m long. The plants are unisexual and florets appear at the top of the palm stem. Male florets are a dirty, pale yellow and fall off after blooming. The female flowers are small, globose and yellow-green. This species grows small, edible, oblong fruit, orange in colour when ripe. The fruit are borne in large, pendant clusters. Each fruit (date) contains one seed. In its natural habitat birds, monkeys and baboons eat the ripe fruit. Bushpig, nyala and bushbuck feed on fallen fruit and the leaves are eaten by the palm-tree nightfighter butterfly caterpillar.

 

In Africa, the leaves are traditionally used to make mats, baskets and hats. Brooms for sweeping around rural dwellings are made from the dried inflorescences. The midrib of the frond is used to construct fish enclosures. Special skirts made from the leaves are worn by Xhosa boys when undergoing their initiation rites. Palm wine is made from the sap (true to the reclinata name, this palm wine may put the user thereof in a ‘reclining’ mode).

Phoenix canariensis  (Canary Island palm,  Kanariese palm)

Phoenix canariensis

As the name indicates this Phoenix species is a native of the Canary Islands in the North Atlantic Ocean off the coast of Africa.  This large solitary palm generally grows 10 to 20 m high.  The trunk can reach a diameter of more than a meter and is covered with an attractive, diamond-shaped pattern from old leaf scars. Up to a 100 leaflets grow on each side of the central rachis.  The yellow to orange fruits are oval-shaped   and contain a single large seed each.  The fruit is edible, but only a very thin layer covers the seed, not making it worth harvesting. 

On the Canary Islands P. canariensis is sparsely and unevenly distributed on all seven islands and the conservation status is different on each of them. The main threat seems to be hybridisation with P. dactylifera.

 Phoenix canariensis hosting a Harpephyllum caffrum (wild plum) 

P. canariensis is widely planted as an ornamental plant in warm temperate regions.  It thrives in Cape Town and readily grows from seeds, as the many trees on empty tracts of land or neglected properties testify. In New Zealand it has invaded a range of habitats and is considered a ‘sleeper weed’ – a plant that spreads slowly and goes unnoticed until it has become widespread.

 Phoenix canariensis inflorecence with some fruit

Phoenix dactylifera (Real date palm, Egte dadelboom)

 Phoenix dactylifera

It is not known exactly where Phoenix dactylifera originated, but this species has been a staple food in the Middle East for at least 4000 years.  Date palms are medium-sized, growing singly or forming a clump with several stems from a single root system. Although tree-like in form, they do not grow woody tissue, and are able to support themselves with fibrous, stout, overlapping stems that grow to a height of 15 to 25 m.

The date palm is dioecious, with male and female flowers on separate plants that are cross-pollinated by wind.  In commercial production the flowers are often hand-pollinated for better fruit production, and propagation is by cuttings to minimise the number of male (non-fruiting) trees. The leaf rachis is 3 to 5 m long, with about 150 leaflets that are 30 cm long. The gender of the sole specimen in the top part of the Park near the bandstand has not been positively established.

 

The name date comes from the Greek for finger as the fruit is oval-cylindrical. The ripe dates range in colour from bright red to bright yellow, depending on the cultivar. Egypt, Saudi Arabia and Iran are the world’s largest date producers. In South Africa dates are grown commercially in the Northern Cape Province.

Apodytes dimidiata (white pear, witpeer)

The white pear is a protected tree in South Africa and one of the best known forest trees in southern Africa. It occurs in coastal evergreen bush, at the margins of medium-altitude evergreen forests, in open woodlands and on grassy mountain slopes, often among rocks. It is a constituent of the Knysna forests and in that area the white pear comprises 3-9% of the total tree population. The only specimen in De Waal Park can be found below the bandstand and is nearly 10 m tall, which is quite tall for this species.

Apodytes dimidiata can be difficult to identify at a glance. The useful identifying character of this species is the red colour of the petiole and terminal branchlets. It is evergreen with glossy, bright green leaves that have a paler green, dull underside. The bark is pale grey and smooth. A. dimidiata forms small white fragrant blooms. The De Waal Park specimen does not flower in great profusion and the fruit is also scarce. The excellent smell of the flowers attracts insects.

 

Apodytes dimidiata

Apodytes dimidiata leaves and fruit

The small fruit are berry-like and somewhat flattened with a red appendage, resulting in a kidney-like shape. They are very attractive to birds. Black rhinoceros are said to enjoy the leaves and bark.

The wood of A. dimidiata is very hard and was used in wagon construction and for furniture. This tree is also valued in traditional Zulu medicine. An infusion from the root bark is used as an enema for intestinal parasites. The leaves are used in the treatment of ear inflammation.

A. dimidiata is an ideal tree for the home garden as it is not very big, has no messy fruit and its roots do not disturb foundations or paved areas.

 

Harpephyllum caffrum (wild plum, wildepruim)

Harpephyllum caffrum (wild plum, wildepruim)

H. caffrum grows from the Eastern Cape northwards through KwaZulu-Natal, Swaziland, southern Mozambique, Limpopo and into Zimbabwe. It is an attractive evergreen tree for the garden that attracts birds and butterflies, and is popular as a street tree in a number of South African towns and cities. The De Waal Park specimens form an attractive group at the upper, small entrance gate on Upper Orange Street, where their thick crowns and drooping leaves provide welcome shade.

H. caffrum belongs to the Anacardiaceae (mango family), the fourth largest tree family in southern Africa, including approximately 80 tree species and many shrubs. Commercially grown members of the family include mango, cashew nut and pistachio nut.

The wild plum is a large tree, growing up to 15 m tall, and is usually found in riverine forests. The main stem is clean and straight, though the forest form often has supporting buttress roots. The bark is smooth when young, becoming rough, dark grey-brown as it grows older. Branches are very characteristically curved upwards, with leaves crowded towards the ends. 

 

Harpephyllum caffrum green fruit 

The shiny dark green and glossy leaves are sometimes interspersed with the odd red leaf. The whitish green flowers are borne near the ends of the branches throughout summer, with male and female flowers on separate trees. The tasty plum-like fruits first appear green, then turn red when they ripen in autumn; they contain a single seed. The fruit of wild plum are enjoyed by birds, animals, insects and humans. They can be used for making jams and jellies, and even wine. 

The bark is a popular in traditional medicine. It is inter alia used  to treat acne and eczema and powdered, burnt bark is used to treat sprains and bone fractures. It is also used for dyeing, giving a mauve or pink colour. The wood of the H. caffrum is pale reddish and fairly heavy. It polishes well but is not very durable. It is used for carving curios.

 

The generic name Harpephyllum is of Greek derivation, meaning sickle-like, referring to the shape of the falcate leaflets. The specific name caffrum is derived from its place of origin, Kaffraria, now part of Eastern Cape. This word also means ‘indigenous’. H. caffrum may be confused with the Cape ash, Ekebergia capensis. but is distinguishable by its sickle-shaped leaflets and the leaves that are crowded towards the end of the branches.

A Shady Corner

One of the shadiest areas in De Waal Park is the south-eastern corner near the small gate on Upper Orange Street.  This deep shade is cast by a variety of very different kinds of trees, among them the largest specimen of Quercus ilex (Holly oak) in the park and a  Brachychiton populneus  (Kurrajong).

Quercus ilex (Holly oak, Holm oak, Holm-eik)

 

Quercus ilex, known as holm oak or holly oak, is a large evergreen tree native to the western Mediterranean region.  It’s toothed and somewhat spiny leaves explain its name, holm being an ancient name for holly.

The bark of Q. ilex is blackish. The leaves are dark, shiny green above and below they are densely covered with whitish-grey short hairs. The leaf shape is variable with adult leaves  4–8 cm long. Leaves on the lower branches of young trees are often larger.  In spring catkins make their appearance and the acorns develop to full maturity within one year.

In its native habitat Q. ilex grows in relatively arid climates and often at low or moderate elevations. It can withstand wind and pollution and has adjusted well to conditions in De Waal Park. The wood is hard and tough, and has been used since ancient times for general construction purposes and for wine casks. It is also used as firewood and in charcoal manufacture. Another interesting use of the holm oak is in the establishment of truffle orchards, where it is one of the three major tree species used. The truffles grow in association with the tree roots.

 

Quercus ilex acorns

The acorns, like those of the cork oak, are edible when toasted or used as flour, and in their natural habitat are also fodder for free-range pigs.

 

Brachychiton populneus (Bottle tree, Kurrajong)

Brachychiton is a genus of 31 species of trees and large shrubs, 30 of them native to Australia and one from New Guinea. The Brachychiton in De Waal Park is a B. populneus, a tree well known and loved in New South Wales. 

It is of medium height with attractive, bright green leaves and has a typically stout, smooth stem, where water is stored during periods of drought. The spongy wood has no commercial use.  The De Waal Park specimen is evergreen, though some species lose their leaves in the dry season.  Brachychiton trees all carry separate male and female flowers on the same tree.  Many of the species have brightly coloured flowers, but B. popluneus has creamy white flowers that appear in summer. The female flowers have separate carpels which can each form a woody pod containing several seeds.

The name Brachychiton is derived from the Greek  brachys, short, and chiton, tunic, a reference to the loose seed coats. Kurrajong, the indigenous name forBrachychiton, means ‘fishing line’ and refers to the stringy bark of the tree that was used for making fishing nets. In Australia the tree is used as fodder in times of drought when the whole tree is lobbed and then allowed to grow again. 

Some Kurrajong species have been introduced to hot, dry regions across the world, including the Mediterranean, South Africa and the western parts of the United States.  

Brachychiton populneus flowers

Brachychiton populneus seed pod