The roots of trees and many bushes maybe of other plants also do somtehing called hydraulic redistribution.
I was taught or imagined that all roots took up water from the ground and carried it to leaves however-:
Scientists have put measuring instruments, called the bean heat system, if i remember right, on roots, that measure the direction of the flow of water and nutrients and found that -:
For one, if superficial roots are losing water to the ground rather than picking it up, some thing i also did not know could happen, i thinks its called negative flow, then the water being taken up from deep within the soil gets taken to the tips of the superficial roots as well as to leaves, the deep roots feeding the shallow ones.
So were there is a tree or bush in hot weather the ground may be damper than where there are not trees and bushes favouring other plants that grow around them.
This means the flow in superficial roots reverses and instead of flowing from the roots to the leaves water flows from the mmmain root the vcentre of the tree out to the tips of the roots.
Two, The scientist also discovered, that in a summer
shower of rain the superficial roots start to take up water again but some of this water gets taken not just to the leaves but down into the depths of the earth down the tap and sinker roots and is stored in the earth.
The flow in tap and sinker roots stops being upwards toward the leaves and becomes downward. Pretty way out what!
This rather changed my idea of the function of roots and there inmportance to the plants around them.
This trememdously backs up the idea that it is useful to have trees and bushes close to other plants. agri rose macaskie.