’ 
EFFECT OF SETTLEMENT UPON INDIGENOUS VEGETATION. 199 
by ringbarking and he gives the measurements and outflow of 
these creeks in corroboration. In this I am able from personal 
observation to support him. I have had many opportunities of 
seeing that the amount of water in creeks is increased by clearing, 
although not always to so great an extent as mentioned by him. 
The following quotations supply what he considers to be the 
reasons of such increased outflow. ‘‘ First, the roots of the trees 
decaying may act as a sort of subsoil drainage, leading the water 
down into the subsoil and afterwards allowing it to drain off slowly 
into the watercourses. If this is the only cause, one of the greatest 
advantages of ringbarking will be but temporary. The other 
explanation—and the one which seems to me most probable—is, 
that when timber is dead the large proportion of the rainfall which 
was formerly taken up by the roots of the growing trees and 
evaporated from their leaves is allowed to find its way to the 
creeks and rivers. The fact that the Eucalyptus is perhaps the 
most vigorous growing tree known, and that it has been used 
successfully to dry up swampy land in other parts of the world, 
seems to support this explanation.” 
It is the former action of ringbarking above alluded to that 
causes the improvement in grass land, which that operation is so 
well known to effect.. The moisture lying in the ground being 
drained off, the sourer grasses and herbs have no longer a suitable 
habitat and die off to give place to sweeter and better feed. I 
have seen a paddock formerly clothed principally with Apple trees 
(Angophora intermedia) and covered with rushes, sedges, sour 
grasses, mosses and hepaticee, and in the course of a few years 
after ringbarking, all the worthless plants had disappeared and 
the paddock was covered with sound sweet feed. Further, from 
being a very boggy piece of land in wet weather, it changed into 
solid enough ground. | 
The conclusions I arrive at therefore are (1) that deforesting 
and ringbarking do not dimimish sainfall ; (2) that these opera- 
tions dry the air, and render the effects of hot winds more felt ; 
— 
* Op. cit., pp. 100-101. 
