TURNIP GRUB. 
101 
amount of the grubs; and in cases like the field Cabbage-growing 
near Isleworth, may be presumed to answer as it is practised, but this 
is very different to working out the grubs from the large-leaved root- 
crops. 
Well stirring the surface with hoes and drags has been found to 
answer, by throwing out a portion of the grubs to Starlings, Rooks, 
&c.; also Pigs have been found to search busily for the grubs, and here we 
may very possibly have one means of prevention that can be used at 
little cost. 
It seems plain that the attack, which begins each year about 
August, cannot come from any other source excepting from the eggs 
laid by the moths which appeared a little before, about the middle of 
the summer, from chrysalids in the ground. We know that the cater¬ 
pillars turn to chrysalids in the ground about May or June, and from 
all this it seems to me that where fields are known to have been 
infested it would be highly desirable, when they are being ploughed in 
the winter or spring following the ravages, to look whether the 
caterpillars or browm chrysalids were being turned up by the plough, 
and if so to have them hand-picked by children at so much a quart, 
or to turn on pigs to root them out. 
The caterpillars or chrysalids may, of course, be more or less in 
many places, but we know that they are present in legions in many 
fields, and therefore that these infested fields are the places from 
which the moths will be likely to come out in corresponding numbers 
and infest the neighbouring fields; and therefore, as far as we see at 
present, it appears that we have no better way of forestalling attack 
than to look out for and destroy the grubs in infested land. 
