General Info

This dioecious Tree is our tallest yellowwood. Shed bark reveals the much lighter underbark. The simple, decurrent Leaves are twisted at the base. Fruit lacks a swollen receptacle.

Description

Afrocarpus falcatus, Podocarpus falcatus, Decussocarpus falcatus, Nageia falcate, Nageia meyeriana, Podocarpus gracillimus, Podocarpus meyerianus, Taxus falcata.

RSA Tree No. 16.

Common names: Outeniqua Yellowwood, Outeniekwageelhout, Sickle-leaved Yellowwood, small leafed Yellowwood, Common Yellowwood, Bastard yellowwood, Falcate Yellowwood, Smooth-barked Yellowwood.

Family: Podocarpaceae. (A large family of mainly southern hemisphere conifers, which includes our Yellowwoods). Leaves are deciduous or evergreen and linear to narrowly ovate. The evergreen trees or shrubs are dioecious. The perianth is absent. Male cones usually have many fertile scales each with 2 pollen sacs. Pollen grains usually have 2 air-bags or wings. Female cones have 1 or 2 fertile terminal scales and a few sterile scales. Ovules are solitary, inverted and enclosed in an epimatium (part of the scale supporting the ovule develops into a rounded covering enclosing the seed entirely). The Seeds, with 2 cotyledons (seed leaves), are borne on a receptacle, which is often swollen and fleshy. The seeds are not in cones. There are about 17 genera and 125 species in this family. Podocarpus and Afrocarpus are the only genera in southern Africa.

Name derivation: Podocarpuspodo(foot) karpus(fruit) referring to the fleshy receptacle on which the seed rest. However, in this tree, the swollen receptacle is absent. This resulted in the name change: Afrocarpusof Africa.  falcatus – sickle shaped (referring to the leaves).

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

Tree

This is the tallest of our yellowwood Trees: reaching 20-60m. The tree has a straight stem and is the quickest growing of our indigenous yellowwoods. In an open landscape, it has a dense pyramidal canopy. Branches tend to droop. Current year branches are green. Bark is a distinguishing characteristic. In young trees, the bark is smooth, thin, and rather greyish to purplish dark brown or chocolate coloured. In older trees, the bark is shed in round or chunky flakes. Directly after shedding parts of the bark, the much lighter red-brown underbark is temporally exposed (photo 284). This occurs in midsummer. This soon darkens but the scars are still visible (photo 328). Young branches are usually ridged by downward sloping leaf bases and are square with nearly opposite leaves. Trees may survive for over a thousand years.

Leaves

On this evergreen tree the Leaves are simple. Younger leaves are broad, light green and soft. The blue-green Mature leaves are linear-lanceolate. However, they can also be lighter and slightly yellowish. They are spirally arranged, opposite or whorled, and often with greyish bloom. They may be slightly curved and are twisted at the base holding them upright. The parallel veined leaves are hard, leathery, narrow and up to 5 x 0,6cm. The Midrib is just visible on lower surface and is slightly raised on upper surface. The Apex is sharply pointed and the Base tapers. Margins are entire (with a continuous margin, not in any way indented), decurrent (extending downwards towards the stem) and, as a result, the Petiole (leaf stalk) is short and may be twisted or absent. Stipules (basal appendages of the petiole) are absent.

Photo 30 L-R: P. falcatus (Afrocarpus falcatus) and P. elongatus showing stomata. Photo 59 shows leaves of different indigenous Podocarpaceae species. L-R: P. latifolius; P. henkelii; P. falcatus (Afrocarpus falcatus) and P. elongatus. This is the order that they were planted at Walter Sisulu – moving away and slightly uphill from the waterfall.

Reproduction

The Tree is dioecious (males and females are on different trees). It takes about 10 years for cones to start developing in axillary buds. Male cones are brownish and small. They are up to 1,3 x 0,4cm and catkin-like (catkin – a scaly-bracted, usually flexuous spike or spike-like inflorescence) and form an elongated cluster of single sex structures attached to a rachis (main axis). Petals are absent. These cones are made up of fertile scales, each having 2 tiny Pollen sacs containing microscopic winged pollen grains. They develop in November on previous year’s twigs and take up to a year to completely mature. The small Female Cones are about 10 x 2mm. They are solitary, axillary (between stem and petiole) and are not produced every year. The Ovules are solitary and attached to the fertile scales. Unlike other indigenous yellowwoods, the swollen receptacle is absent.

Fruit

The Fruit grows on a woody stalk. N.B. unlike other yellowwood species the fleshy receptacle (base) is missing. This helps to distinguish it from P. latifolius, which has a slightly swollen fleshy receptacle. The Seeds do not occur in typical woody pinecone structure. In spring, the Fruit becomes yellow and fleshy and usually surrounds a single, hard rough seed. This occurs with the new leaves. Part of the scale supporting the ovule develops into a rounded fleshy covering, which encloses the seed entirely. This false Aril is known as the Epimatium. The single seed contains 2 Cotyledons (seed leaf; primary leaf or leaves in the embryo). (Sep-May).

Distribution & Ecology

These Trees are found in the southern Cape (e.g. the Big Tree at Knysna), through KwaZulu-Natal, Western Soutpansberg (far northern RSA) and Blouberg, Mpumalanga and Limpopo – from the coast up to an altitude of about 2 000m. The tree is shade tolerant. It grows best in deep, slightly acidic well drained soils. Trees are also found in Swaziland, Mozambique, Kenya, Tanzania and Malawi. Many birds make their nests in this tree including the African olive-pigeon or Rameron pigeon, and the endemic Cape parrot. The fruit is consumed by Knysna Turaco and some pigeons. Monkeys, bushpigs and rodents also eat the Fruit but apparently do not help with dispersal. Fruit bats – including Egyptian fruit bat (Rousettus aegyptiacus) also feed on the fruit and play a part in the seed dispersal. There is a mutualistic relationship between the roots and a mycorrhiza which aids the tree in capturing nutrients e.g. nitrogen, sulphur and phosphorus. The fungus gains carbohydrates such as glucose from the roots. This type of mutualistic relationship with plants has existed for a long time.

Ethnobotany

The fine textured, pale yellow to pale yellowish brown Wood, lacks resin and is easy to work with. It and known commercially as Podo. It is used for shipbuilding (the density is about half that of water and thus floats well), for furniture, flooring, roof beams, boxes, for making plywood and musical instruments. Bark can be used for tanning leather. The ripe Fruit is edible. A chemical, Podolide, has been extracted from leaves and has been shown to have in-vitro anti-leukemic properties. This is a protected tree in South Africa. The tree grows relatively slowly. A young un-pruned tree casts a deep shade and inhibits grass from growing beneath it. The stem age can be roughly calculated by multiplying the stem diameter, in cm, by 4. Thus, a tree with a trunk diameter of 50cm would be about 200 years old. Large trees may extend above other trees in the canopy and their roots can cause problems with foundations. Trees developing below the canopy grow more slowly until they can obtain more light. In the forest, the trees are self-pruning but in the open they do require pruning. In order to cut this tree down a licence is required in South Africa. Trees can be harvested for use after about 50 years. The wood needs to be protected from fungal and insect attack.

References

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

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

 

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

http://edis.ifas.ufl.edu/st492

http://www.biodiversityexplorer.org/plants/coniferophyta/podocarpaceae/afrocarpus_falcatus.htm

http://www.saforestrymag.co.za/articles/detail/outeniqua_yellowwood_the_majestic_tree_of_our_natural_forests

http://www.plantzafrica.com/plantnop/podocarpfalcat.htm

http://redlist.sanbi.org/species.php?species=3778-2

http://www.prota4u.org/protav8.asp?g=pe&p=Afrocarpus+falcatus+Thunb.+C.N.Page

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

https://www.conifers.org/po/Podocarpaceae.php