MONTHLY NOTES ON GRUBS AND OTHER CANE PESTS. 49° 
FurTHER NOTES ON THE VALUE OF ARSENIC FOR GRUBS. 
Above I have alluded to the destruction of weeds by the use of 
sodium arsenite. Indeed, I was considerably surprised to find that the 
farmers, under the direction of Mr. Sugden, were so advanced in their 
application of this valuable remedy. The Association has purchased and 
is using most successfully the Vermorel knapsack spray for the eradica- 
tion of weeds in new stump-land. Not only is the process much cheaper 
and easier than chipping, but the effect of the arsenic will be far-reaching 
in the soil for the control of root grubs. 
I was very fortunate in being able to diseuss this important matter 
with Mr. C. E. La Caze, a grower of extensive experience, not only 
here, but also in Mauritius. About a dozen years ago Mr. La Caze was 
farming on the Herbert River, and had serious losses from grubs. Often 
half of his plant-cane was destroyed, and, he said, his losses amounted 
to many thousands of tons on his three farms there. He was faced 
with bankruptcy and decided upon extreme measures. Learning that, 
white arsenic would destroy termites, he at once decided to try it for 
the destruction of the grubs on all of his lands. He hit upon the plan 
of mixing the arsenic with meatworks manure and arranged to have 
the mixing done at the meatworks. As arsenic was then cheap he used 
14 Ib. of the poison for each ewt. of the meatworks manure, and applied 
about 5 ewt. of the manure to the acre, placing it in the drill before 
planting. Between 500 and 600 acres were treated in this way. The 
results were immediately noticeable, and, he informs me, there have 
been no further grubs on that land since. 
This information certainly is very interesting, and appears to be 
conclusive, but Mr. La Caze said that he kept no checks, and also stated 
that some of the feeding-trees were being removed at about that time, 
so it will be well to try similar experiments with arsenic in other places 
before we can decide definitely that the poison was the eradicating factor. 
I wish to urge the importance of trying an experiment with arsenic 
on every grub-infested farm. I do this largely as a result of our success. 
with this remedy at Meringa, where we got excellent results by using 
only 20 lb. of the poison to the acre, mixing it with about 5 ewt. of meat- 
works manure, which was applied in the drill at the time of planting. 
I would suggest that each grower try at least 1 acre, leaving an 
area alongside as a check. The poison may be applied either alone or 
mixed with the meatworks manure; but I think it important to centralise 
the poison by placing it in the drill. I have advised many growers on 
stump-land to test its value by using 20 Ib. of the poison per acre, 
applying it in the cane holes after the plants are covered. In the case 
of ratoons among the stumps, the dry arsenic might be dusted on the 
trash after cutting, placing most of it in the centres. This could be 
done easily by placing the poison in two bags of thin hessian, attached 
at the ends of a pole about 5 feet in length. Holding this by the middle it 
is an easy matter to dust two centres at a time by walking over the row- 
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