Sometimes it can be hard to like October! With the temperature in the house up in the mid thirties and much higher out in the sun, heat becomes the defining feature of every day. Out around the Park, the scenery is starting to look very bleak indeed…..
On the Kashawe loop
Near Lukosi crossing
Mandavu
These are some of the worst places. In others there is still plenty of grass but it doesn’t look very palatable and surely doesn’t have much protein left as it bakes in the sun day after day…
Near the Gubombiri River
Most of the barest places are due to the effects of man and his livestock on the very fragile soils and grasses of the area. Before it was incorporated into the Park in the 1950s, much of the Sinamatella sector was inhabited and we can still find the remains of villages and farms in places - but the most obvious signs of man are the huge areas of bare soil or erosion, still not recovered from overgrazing almost sixty years ago. Even in the bleakest places the Mopane trees, toughest of the tough, survive but grass just can’t get a root-hold in the hard, bare soil.
Mopanes seem to be the Bruce Willises of trees. No matter what is done to them they come staggering back for more, a little wounded, some pieces missing perhaps but they definitely die harder. A few other trees have more subtle strategies and they can become startlingly obvious at this time of year. On some recent trips, when we were making mammal counts, Sue photographed a few of the trees that are starting to show green leaves but don’t seem to attract the attention of the elephants…
This one is a candelabra tree, Euphorbia ingens. Its green parts are not strictly leaves and they are green throughout the year but there is no mistaking the tree’s survival strategy. All parts of it are poisonous and even honey made from the flowers is said to be inedible. There are even worse members of the genus. I well remember collecting parts of a Euphorbia cooperi in the Zambezi valley and only later, when the damage was done, reading in Coates Palgrave’s “Trees of Southern Africa” the warning…….‘The latex has a pungent, acrid smell and is said to be one of the most poisonous of the Euphorbia species, causing intense skin irritation and even producing a burning sensation in the throat if one stands too close to a bleeding plant. If material is being collected, care should be taken to wrap the branches in some protective covering’. I can vouch for the fact that this is good advice!
Much tastier in appearance than the Candelabra tree is the Ordeal tree, Erythrophleum africanum…..
We don’t have a lot of this species around Sinamatella because it prefers deep Kalahari sand, more typical of the Main Camp sector, but where it grows it really stands out with its soft green leaves amidst the dry Combretum that usually grows with it. Like the Candelabra tree, Ordeal trees are poisonous and parts of the closely related Forest ordeal tree were formerly used in a sort of trial by ordeal to test people accused of serious crimes such as witchcraft. It clearly works just as well on elephants because they leave it well alone.
Another real stand-out tree at the moment is the Sausage tree, Kigelia Africana.
This one is a well-known land mark at the Lukosi river crossing on the Tshakabika road and in spite of a high density of elephants in the immediate area (where they dig for water in the river bed), it shows green leaves when everything else is dry but it never gets eaten. Coates Palgrave says the fruits are said to be poisonous but there is no mention of other poisonous properties and I know squirrels enjoy eating the green fruits while they are still on the tree and porcupines eat them when they fall. The flowers are also eaten by many animals so perhaps the leaves are simply unpalatable. Maybe I’ll taste one next time I get the chance – though my sense of taste is not much like an elephant’s so that may not prove a lot.
A similar puzzle is the Tree wisteria Bolusanthus speciosus.
This one, growing near Shumba, looks tasty enough and the books make no mention of any poisonous properties but there must be some reason why the browsers leave it well alone and eat dry twigs instead.
Most of the trees though, like us, are just waiting patiently for the heat to go away and the rains to come. We’ve had a little cloud in recent days so rain might not be far away.
Clouds at sunset, Sinamatella.
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