The Not-So-Common Trees - White silk cotton tree
Currently named Ceiba pentandra, the white silk cotton tree was earlier known as Eriodendron anfructuosum. The adjective, white, is a reference to the colour of the flower as against the colour of the flowers of Bombax malabarisum, the red silk cotton tree. The white silk cotton tree, or ilavampanju, the Tamil name of the tree, is far more common in Chennai than the red silk cotton tree. It is seen growing in the backyards of many a home in Chennai. The Jeeva Park on G N Chetty Road, T Nagar, has quite a few of these trees.
Mostly it grows on its own, without any deliberate human intervention, a point explained by the dispersal of the seed by wind. The dispersal is aided by long silky hairs that line the dark seeds. It is these hairs that constitute the material of economic value for it is used to stuff pillows, cushions and even mattresses, rendering them extremely soft and very pleasant to repose upon.
My readers might wonder as to why the silk cotton is not used for making cloth like cotton. After all, both are epidermal hairs growing upon the seeds. A point worthy to ponder!
You'll find the answer if you make a comparative study of the two hairs. The cotton hair stands firm and straight, when taken into the hand while that of silk cotton, immediately collapses. Now, why? If you examine the two hairs under a microscope, you have the answer.
The hair of silk cotton is completely hollow inside, filled with air. But the cotton hair has a spiral band of cellulose lining its inner wall, rendering it strong, and remain straight. So, the hairs of cotton can be made into threads, giving you the yarn.
Now, another interesting fact: These hairs are made up of cellulose, which lends them a smoothness. On the other hand, fibres that make up coir or jute are made up of different wall material, called lignin. Lignin is much stronger but rather course and therefore not good enough to make quality cloth, though alright to make ropes and bags. After all, man’s tactile sensitivity would make it uncomfortable wearing such cloth.
Cellulose, though not as strong as lignin, has a smooth feel, something which is comfortable to the human skin. This is why cotton is the raw material for making textiles: it is endowed with two very desirable characteristics, as far as man’s tactility goes: reasonably strong and quite smooth. But the ‘Kapok’, the commercial name for silk cotton, is smooth but has nothing to make it strong. In the circumstances, man found another use for it: stuff the pillows, cushions and mattresses, making them extremely soft and smooth - properties that make you comfortable as you lean or lie on them.
The white silk cotton tree is a tall- to medium-sized tree, whose trunk is prickly when young, but quite smooth when old. Uncommonly, the surfaces of the trunk and also branches tend to remain green, possibly because the chloroplasts in the subepidermal region remain alive: a point worth investigating. Of course, absence of bark formation can also be a contributory factor for this.
The branches arise in threes, growing horizontally outward. The leaves are compound, held on a 10-15 cm long stalks,
with 5-8 leaflets growing out like the digits of a palm. The flowers are whitish to yellowish. The fruits are rather conspicuous with an ivory
colour. They are quite large and are formed when the leaves are shed, facts that add to their conspicuity. As the fruit breaks up, the seeds float out into the air with all those air filled hairs growing upon them.
The roots are diuretic (inducing urination) and aphrodisiac (increasing sexual vigour). The bark is also diuretic and counters abdominal disorders, such as enlargement of liver and spleen.
