84 SOME CAUSES OF THE DECAY OF AUSTRALIAN FORESTS. 
visibly affected by the destroying agent, whatever it was. Now 
upposing drought to be the agent, it could not have acted so un- 
equally. Still further, when the drought ended, the decay 
continued among the trees between 1870 and 1874. This was 
proof that the particular cause of decay in this case, at least, was 
to 
concentrates their ravages upon the leaves of the gum-tree forests, 
and along with drought would help to account for trees dying near 
permanent water, a phenomenon which has been very puzzling to 
observers in this matter. 
. Bush fires.—Great conflagrations took place in 1863 and 
1865, the flames sweeping over a large portion of country to the 
west of the railway line in the Meredith District. Numbers of the 
trees for a time seemed as if they had been fatally injured. The 
leaves became of a sickly yellow colour, very like the hue presented 
by those on trees which have been ringbarked. The trees, how- 
ever, in this case did not die, except in a few instances. A la 
number of shoots burst forth from the main trunk of the trees 
which survived the scorching. In two or three seasons the 
of seven or eight seasons this change was great enough to p 
had before. But the decay among the trees continued long after 
those fatally injured by the bush fire had died away, and after 
those partially injured by the scorching had recovered. Trees 
which had stood against both droughts and fires in 1863 and 1865 
rer, dying in thousands in a comparatively favourable season in 
871 
esca 
so deep into the prevailing soil or soils as the older ones. 
9. Sheep manure.—That powerful chemical decoctions arising 
from sheep manure would be sufficient to burn and kill the roots of 
gum-trees may be likely enough if the agents could be shown to 
operate in sufficient quantity and over the areas on which the 
trees are dying. Sheep-yards have been pointed to as affording 
