Monthly Notes on Grubs and other Cane Pests. 
By J. F. ILLInewortuH. 
CANE GRUB INVESTIGATION, JULY, 1918. 
I have been greatly interested in the rather general acceptance of 
the idea of late planting for infested soils. Almost everywhere we go 
we find the farmers routing out the grubby fields; and a number 
have told me that it is their intention to work the ground thoroughly, 
preparatory to late planting. There is certainly no time like the present 
for killing weeds; and if the soil is kept clean-fallow until September, 
the cane should require very little chipping, thus removing one of the 
great objections to late planting, 7.e¢., the difficulty of keeping the crop 
clean during the wet weather. Let me repeat, then, and urge that all 
infested soils, especially the red volcanic, be thoroughly worked and 
kept in clean-fallow until planted in September or October. During 
the process of ploughing three or four times it is possible to work a 
great deal of trash and other organic matter into the soil; this is worth 
all the extra effort required to conserve this humus-forming material, 
for, as explained further on, it undoubtedly is a vital factor in grub 
control. ° 
Let me again call attention to a very interesting experiment at 
Greenhills, where in one field (L6) half of the cane was planted in June, 
1917, and the rest in October. The latter half is now beautiful cane, 
very erect and green, in marked contrast to the early-planted half, which 
went down in the cyclone after a bad attack of grubs. Furthermore, 
this early cane has deteriorated so much that it is very doubtful if any 
of it will be fit for milling. This field is particularly interesting because 
the two plantings are side by side, having the same care, and exactly 
the same soil. 
ON THE VALUE OF ORGANIC MATTER IN THE SOIL. 
Early in experimentation, from our knowledge of the feeding habits 
of the grubs, I was convinced of the value of humus-forming material 
‘as a factor in their control. Hence, we have followed the matter up 
with increasing interest. 
