Outeniqua Yellowwood
Created | Updated Dec 2, 2012
Outeniqua Yellowwood
Willem says: 'The Phyto-Philes are for plant lovers of every size and shape, colour and flavour. As with my Colours of Wildlife column, I'll be featuring one species per article, illustrated with sketches, paintings, and/or photos. Over time I hope to be showcasing the amazing diversity of weird and wonderful plants that occur in South Africa, while also from time to time looking at the flora of other countries. While featuring many spectacular species, I'll not be neglecting the smaller, more humble kinds that are nevertheless fascinating in their own right.'
Today I feature the Outeniqua Yellowwood, Afrocarpus falcatus. I’ve featured this species in my previous Guide Entry, The Ten Biggest Tree Species of South Africa. It comes in at number two on that list. It is, in terms of potential height reached, our tallest native species. Although at the moment there is not a single known specimen over 40 m/130 f tall, it has been recorded as reaching 60 m/200 ft. This does not compare very well against the tallest trees in the world, the Mountain Ash, Eucalyptus regnans of Australia and the Coast Redwood, Sequoia sempervirens, of America, both of which can exceed 110 m/365 ft in height. But for South Africa this is very tall. As I explain elsewhere, our country is mostly very dry, and short on trees. What is more, the few sizeable trees that can actually be found are under huge pressure from humans. When the Europeans first landed here they noted the tree shortage and documented every bit of forest and woodland they could find, and proceeded to cut these down for wood they needed for whatever purpose. This has been going on since the mid-seventeenth Century, and was worst in the places the settlers reached first, starting with the Cape Colony.
The Outeniqua Yellowwood, being our largest timber tree, was particularly targeted. It has a high-quality general-purpose wood. Growing tall and straight, its trunks were used for making the topmasts and yards for ships. The timber is fine-grained and not resinous, fairly light but relatively hard and strong. As its popular name indicates it has a uniform yellow colour and is only faintly marked by growth rings, since these trees grow in forests that are fairly warm and moist year-round. Apart from masts and general ship-building use it is also suited for high-quality furniture, roof beams and floor boards.
The first large forests the Dutch and later the British found and used to provide them with wood were the forests of the Knysna and Tsitsikamma regions. These forests are somewhat to the east of Cape Town, around the point where the Winter-rainfall region of the Southwestern Cape and the Summer-rainfall region of the Eastern Cape and the rest of South Africa meet. The region therefore receives rain throughout the year. Also, the area consists of a fairly narrow coastal strip with the Outeniqua and Tsitsikamma mountains rising inland and travelling parallel to the coast for some hundreds of kilometers. Moist air coming in from the ocean rises over the mountains and condenses into rainfall as it cools. The climate is also temperate, never too hot or too cold. This favourable climate and abundant year-round rains support the largest indigenous forest region in South Africa, and the Outeniqua Yellowwood, named for the abovementioned mountain range, is the most striking tree to be encountered here. They have been noted and targeted for centuries and much of the original forest has been cut down. One of our most famous writers, Dalene Matthee, wrote several novels, most notably ‘Kringe in ‘n Bos’ (Circles in a Forest), that feature these forests and the lives of elephants, woodcutters and other people living in them. One traditional Afrikaans name for this species, ‘Kalander’, is prominent in the folklore of the region. A lovely species of forest bird also named for the region is the Knysna Turaco.
So, sadly, most of the large and old Outeniqua Yellowwoods have been cut down. The ones that survive are mostly in inaccessible places such as steep mountain slopes and ravines. But today the species is protected. Especially noteworthy remaining individuals have become tourist attractions; so in the Knysna and Tsitsikamma regions there are ‘big trees’ that are noted on maps and in brochures. Some tourists have expressed disappointment at the trees not being as big as they expected. Again, it’s relative. Where I grew up, and where I still live, it is unusual to find a tree more than five metres tall. Indeed, because people cut down even medium-sized trees for firewood, there are extensive areas of ‘dwarf savannah’ of stunted thorn trees the canopies of which rarely exceed two metres in height. With this background, it inspires me with absolute awe to look at a tree that is standing more than thirty metres tall.
But the impressiveness of these trees cannot be reduced to a simple measure. They are indeed quite tall, but apart from that they have massive trunks, in very large specimens forming into flutes and buttresses to give it lateral support, growing straight until the crowns emerge above the rest of the forest canopy. There the trunk spreads into long and stout limbs carrying the broad, dense crowns. These spread out and overshadow the surrounding tree crowns, ‘stealing’ their sunlight so to speak. In fact in forestry circles a large Outeniqua yellowwood specimen is sometimes considered to be almost a parasite so much does it oppress the growth of its neighbours! My painting shows the crown of a yellowwood that emerges above the canopy like this. But apart from size there are other factors of grandeur. These specimens are certainly very, very old. It is not quite clear just how old these trees are, but certainly in some cases we’re speaking of many centuries. While this tree has a bark that sheds in rectangular flakes, which makes it difficult for climbing or clinging plants to get a hold on it, the branches of very old specimens are typically draped with long strings of Old Man’s Beard, a kind of lichen. Those are interesting in their own right, being an extremely intimate association between two vastly different species, the one an alga and the other a fungus. Other epiphytes (plants-growing-on-other-plants) also manage to grow in the crowns, most often ferns. I’ve seen a number of species of plants that are not considered actual epiphytes also growing on them. That is because these trees are so big that, in some nooks and crannies between the branches, and over many centuries, deep pockets of soil can form from dropped leaves, flaked bark and blown dust. So, I’ve seen growing in the crowns of yellowwoods things like forest lilies, which are ordinarily found on the shady forest floor, and aloes, which are typically found growing on rocky cliffs around the margins of the forest.
Apart from the Knysna/Tsitsikamma forests these trees can also be found in the many smaller indigenous forests of South Africa. The closest wild ones to my home town of Polokwane are found in the Magoebaskloof region stretching from Haenertzburg to Duiwelskloof and Tzaneen. Large ones can be seen along the forest drive in the Woodbush and De Hoek state forests. But more impressive ones I’ve seen are in the Wonderwoud (‘Wonder Forest’) of the Wolkberg Wilderness Area, a wild and mountainous region where woodcutters could only enter with great difficulty. On a hike through this forest I’ve encountered several individuals all of which are in the 30 m or more size range. But the most impressive one is in the Lekgalemeetse Nature Reserve just to the south of the Wolkberg. This one can only be reached after a very strenuous hike up mountains and through narrow gorges. At the end of this one emerges on a high plateau and then has to hike a bit further to get to it. It grows in a patch of forest seemingly all its own … it is so large that its shady canopy shelters a number of smaller forest trees and substory plants around it. This one has a very thick trunk that’s actually wider a distance above the ground than it is at its base, and it has a very widely spreading crown. It gave me feeling of reverence to meet this ancient tree that has been growing here above the mountains for centuries, to stand in its shade listening to the birds and the monkeys whose lives it has supported for so long.
People who know a bit about the ancient history of the Earth will be even more reverent about this tree. It belongs to the Podocarpus family. These trees grew on the ancient southern continent of Gondwanaland since before the time of the dinosaurs! They even grew in Antarctica, which is entirely treeless today of course. Podocarps thrived in the cool-temperate climate of the southern continent. They formed extensive forests of massive trees. Podocarps are relatives of needle-leaved and cone-bearing trees like pines and firs. But they have flattened, sickle-shaped leaves, and the female trees bear berry-like fruits rather than cones. These provide food for many birds and mammals. The male trees bear small cones. When Gondwanaland broke up, podocarps were carried along with the various pieces and kept evolving. Some of them spread into humid tropical regions, often along mountains where the climate was cooler, but they are still mostly restricted to the southern continents: Africa, South America and Australia. They reach their northern limits in Central America and the Carribean, Northeast Africa, and Southeast and far-eastern Asia up to Japan. There are currently more than a hundred and fifty species recognized. The main genus, Podocarpus, is the largest; the Outeniqua Yellowwood used to be placed in it but is currently split off into the genus Afrocarpus along with a few other exclusively African species.
These trees are widely cultivated. They can be fairly easily grown from seeds, provided the flesh is removed from them, and many are grown in suburbs in my own town. I have one in my garden and there’s a bigger one in that of my neighbours. The photos I include here show one that is planted on the grounds of a church. This tree is about ten metres tall. My father is scanning the ground for fallen fruits and seeds. The second photo is a close-up showing the branches, the small, dense leaves, and the flaky bark. Cultivated trees don’t look like wild ones: growing outside of forests they start branching only a short distance above the ground rather than forming tall, clean boles. Also they don’t become nearly as big … or at least not within one or two human lifetimes. But they are still very ornamental with their neat, dense canopies. They are in fact good choices for living Christmas trees suitable to South Africa … they can be grown in pots and taken in and out with ease. Yellowwoods can handle mild frost and short droughts (once planted out in the soil – in bags or pots they must be watered regularly), and have a moderate growth rate. If it were up to me I would re-plant these trees in large numbers wherever they’d been eradicated, along with other indigenous South African forest tree species.