34 MONTHLY NOTES ON GRUBS AND OTHER CANE PESTS. 
I have recently instituted careful surveys in the infested areas by 
counting the number of grubs per stool of cane. As a typical example 
of this method, I may eite the field of first ratoons, H1, at Greenhills, 
where, by working at a gradually increasing distance back from the 
forest, we got the following grubs:—14, 13, 15, 8, 3, 1, the last stool 
being just about on the half-mile from feeding-trees, to windward. 
Another excellent example, which works out in perfect accord with this 
theory, is an infested farm near Gordonvale. Feeding-trees border it to 
windward, south and east, and the principal infested areas are on the 
side towards this timber. The worst-infested fields, A and EH, are.now 
out of cultivation, having failed completely last season. However, I was 
able to get the following remarkable figures, by taking the average of a 
series of stools :— 
12 chains from the forest, 45 grubs per stool, Badila, 1st ratoon. 
16 chains from the forest, 17 grubs per stool, Badila, 1st ratoon. 
18 chains from the forest, 13 grubs per stool, Badila, Ist ratoon. 
22 chains from the forest, 12 grubs per stool, Badila, 1st ratoon. 
28 chains from the forest, 7 grubs per stool, Goru, Ist ratoon. 
35 chains from the forest, 5 grubs per stool, Goru, 1st ratoon. 
40 chains from the forest, 0 grubs per stool, Goru, 1st ratoon. 
The same decrease in the number of grubs per stool is shown in 
every part of the farm as one recedes from the feeding-trees. 
CULTIVATION EXPERIMENTS. 
As stated in my last report, I was unable to get these experiments © 
started in time to derive the maximum benefits therefrom. Nevertheless, 
the experiments show that there is no material difference between work- 
ing the soil once a week and once a fortnight; also, that the plough is 
considerably more effective i disturbing the grubs. 
Every Week. 
Plough .. ae .. Average number of grubs per stool, 5 
Cultivator a .. Average number of grubs per stool, 83 
Harrow .. ols .. Average number of grubs per stool, 93 
Every Fortnight. 
Plough .. ae .. Average number of grubs per stool, 6 
Cultivator Sic .. Average number of grubs per stool, 8 
Harrow .. 46 .. Average number of grubs per stool, 72 
Check?) ae nt .. Average number of grubs per stool, 133 
The check in this case does not show its true value, because it was 
cultivated twice after the experiment began in spite of my instructions 
to the contrary. Still, the better cultivation in the other plots is very 
noticeable from the figures. 
There is very decided evidence that cultivation as a means of control 
must begin during the two weeks after the beetles emerge, before they 
start laying. Apparently, once the eggs are deposited it is a difficult 
