Page:Enquiry into plants (Volume 1).pdf/87

 if it is light open and porous, contributes greatly to deep rooting, and still more to the formation of long roots; for in such soils growth goes further and is more vigorous. This is evident in cultivated plants. For, provided that they have water, they run on, one may say, wherever it may be, whenever the ground is unoccupied and there is no obstacle. For instance the plane-tree by the watercourse in the Lyceum when it was still young sent out its roots a distance of thirty-three cubits, having both room and nourishment.

The fig would seem, one may say, to have the longest roots, and in general plants which have wood of loose texture and straight roots would seem to have these longer. Also young plants, provided that they have reached their prime, root deeper and have longer roots than old ones; for the roots decay along with the rest of the plant's body. And in all eases alike the juices of plants are more powerful in the roots than in other parts, while in some cases they are extremely powerful; wherefore the roots are bitter in some plants whose fruits are sweet; some roots again are medicinal, and some are fragrant, as those of the iris.

The character and function of the roots of the 'Indian fig' (banyan) are peculiar, for this plant sends out roots from the shoots till it has a hold on the ground and roots again; and so there comes to be a continuous circle of roots round the tree, not connected with the main stem but at a distance from it.