20 
CORN AND GRASS. 
letter with which I am favoured by them, from Mr. S. Osborne, 
Springtown, near Londonderry, appears well worth notice, amongst 
other points, with regard to preparation of the ground. There is no 
doubt that a difference in the method of cultivating the surface of the 
land has an effect on amount of increase of some kinds of crop-insects, 
independently of all other considerations, and (without going back to 
bygone methods of cultivation) the effect of some of these may help 
in showing which of those of the present day will act best on the 
grubs, as well as for ordinary agricultural purposes. 
In the following notes Mr. Osborne draws attention to the trenching, 
which disposes of the grubs so deeply down that they have difficulty 
in coming up again ; the double-furrow plough, that presses the clods 
together, and turns the sod smaller and lighter for the harrow to break 
up, is also in a different way good for getting rid of the grub; whilst 
another form of ploughing is noticed as, though good in itself, being 
at the same time especially favourable for grub harbouring. Mr. 
Osborne first remarked :— 
“I promised to give you a short report of my experience of the 
grub-worms. 
“ I have only made their acquaintance within the last twelve or 
fifteen years on the farm ; prior to that they were little known in this 
neighbourhood. This fact, to start with, suggests many questions. 
Hoiv much is the cultivation altered, and how much does the present system 
contribute to their increase ? 
“ I believe our predecessors destroyed the eggs more than we now 
do by the spade in ridging and deep trenching, cultivating but a small 
area, and not being obliged to level the land for the mowing machines, 
the grub made less ravages. 
“ The grubs do not make such headway when there are deep- 
trenched furrows, and they have been seen lying helpless in these 
trenches in hundreds. I find that rolling is no preventive. Ploughing 
has somewhat to do with them. The best ploughman in lea-land 
generally has the worst crop after him in Oats, from the fact that in 
setting up and making a good ‘ cone ’ as a seed-bed he only makes the 
better cover and shelter for the grub. The furrow turned flat over is 
best, but the double-furrow plough has proved to me the best imple¬ 
ment, as it presses the furrows together and turns the sod over much 
smaller and lighter for the harrow to break up, for it is in the crevices of 
the furrows the grubs lie and suck the milk of the grain, which is much 
worse than the cutting of the blade. 
“In my experience any chemicals applied for their destruction 
when they begin to make their ravages must destroy the grain. I have 
had them covered with salt and soot over night, and they have been 
alive in the morning.” 
