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Interesting self protection facts about the Soetdoring tree.

This tree has spend just the right amount of resources in developing its thorns so that it is just long enough to protect its leaves. The thorns are white to advertise to possible would be leaf eaters no not try their luck. It is also spaced in such a way that only small delicate mouths and tongues like those of duiker and giraffe can get access to it.

The leaves can have a very high content of tanine, which is why its bark is used for processing leather. It will happen that an animal will be eating the leaves one moment and then all of a sudden the tanine levels will rise so high that the animal will move off to the next tree.

The name soetdoring comes from where if the tree got damaged it will release this sweet smelling glue to protect and heal the damaged area.

Trees are so interesting.
The fact that a tree can release tanin so that a browser moves on and doesn't overbrowse it is amazing.
I learnt that an animal, like kudu, will die if it takes in too much tanin.

I agree that it is amazing.

BTW, What is the kudu's cause of death? Was it because his leather got processed?

What is the common name of this tree please? I don't have my tree books at hand right now ;o) Would it be the Sweet Thorn?

According to my info, some trees are believed to 'communicate' with others of the same species close by - so that the tanin levels not only increase in the tree which is being browsed, but also in it's neighbours.

As Freda said, there has been a case where a whole herd of Kudu died from tanin poisoning, due to the fact that they were introduced to a small area, with limited tree species, and where the trees had all increased their tanin levels due to over-browsing by the animals.
When they performed autopsies to try to discover why the animals had all suddenly and inexplicably died, they found that, although the animals had eaten very well and had full stomachs, they had excessive amounts of tanin in their blood which resulted in organ failure.

It is Sweet thorn, tabs, but soetdoring sounds better somehow

Whoooo! I finally remembered (or made a lucky guess at) a tree?

Browsers like Kudu and Giraffe therefore adapted.. They have very large saliva glands to counter act the effects of the tannin (ever seen a giraffe drooling?)

Gompou (Kori bustard) eats the sweet thorn' s gum- from there the afrikaans name.

On my way to work today that very few acacias trees have any flowers on them. Normally this time of the year all the trees are covered with yellow flowers but the trees that does have flowers this year, only have few. Is it because of the drought conditions we are experiencing? Does the tree have some sort of mechanism to prevent it from pushing flowers? I think that the tree that we have here is the Acacia Karoo.

Still no reply No experts on trees? Do we all qualify for the "Weakest Link"

Most acacias flowered early in the season. Acacias such as the i.e. the Knobthorn have flowered early spring. But Acacia karoo are known to repeatedly flower, so they may very well flower again, if the circumstances are favourable.

Are you experiencing unusual drought conditions AWB..and if so how long has the drought lasted? Is this the first year they have not flowered in December?

It is indeed a very dry year, but I have never seen the Acacias without flowers this time of the year. We go to Mosselbay every Christmas and every year you find all the Acacias in full bloom, even in the middle of the Karoo, which has half the average rainfall than we have.

In a drought, trees will do what they have to do in order to store water and energy. This may mean a decrease in the amount of flowers and leaves they produce as they seek to reduce water loss through evaporation.

If the tree is very stressed it may also shed perfectly healthy looking branches as it tries to cope.

When we have decreased rainfall here we have reduced leaves and flowers on trees...but the first year the rainfall is back to normal they will produce a larger than normal amount of flowers.