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this method, we should bear in mind the fact that a small number of 
grubs may do a great amount of harm to young corn on comparatively 
clean ground, because of the small amount of vegetation offered to them 
as food while the corn is young. 
Next, we should take into account the relatively small damage done 
to clover by the grubs, and the further fact that we have no present evi- 
dence that the eggs of the June beetle are ever laid in clover land. It 
is consequently a good practice, so far as grub injury is concerned, to 
insert clover (sown perhaps with oats) between grass and corn in the 
rotation; and this is especially to be advised on light soils not  per- 
fectly adapted to corn. Here it will have the effect not only to eliminate 
the grubs in part, but also to diminish the damage to the following 
crops of corn by increasing the strength of the land, thus helping the 
corn plant to withstand such loss of roots as it may nevertheless be 
subjected to. In this connection it need hardly be said that a generous 
treatment of the soil, by heavy fertilization, thorough cultivation, and 
the like, will diminish loss to corn by enabling plants attacked to throw 
out new roots more vigorously to take the place of those eaten by the 
grubs. Indeed, by some most intelligent and successful farmers, high 
fertilizing with frequent rotation is regarded as the essential and suffi- 
cient defense against these insects. 
The management of corn on lands containing grubs should also be 
directed especially to the protection of the plant from drouth, as, in the 
presence of these insects, dry weather takes a double effect by retarding 
root growth under circumstances which require it to be vigorously stim- 
ulated instead. 
To prevent the laying of the eggs of the June beetle in the corn 
field in May or June, it is desirable that the ground should be kept 
practically free from weeds at that time, as it is ‘well known that a sur 
face growth of vegetation is a strong attraction to these insects search: 
ing for places suitable for the support of the young. Some of our more 
recent observations show that the beetles are likely to deposit their eggs 
in the field from which they themselves have emerged, provided that it 
offers them suitable conditions—a fact which makes it clearly inadvisa- 
ble that a field which is badly infested one year, should be planted to 
corn the next. 
General Prevention.—The principal and most effective preventive 
measures of general promise are those for the collection and destruc- 
tion of the June beetles before they have laid their eggs. They are 
practically confined to the following four methods, mentioned in the 
order of their importance: (a) shaking and jarring down the beetlés 
at night from the trees in which they feed, and their collection on sheets 
or cloth-covered frames similar to those in use for the peach and plum 
eurculio; (b) exposing light traps early in the evening in places fre- 
quented by the beetles ; (c) the spraying of trees to which they resort, 
with Paris green or other suitable insecticide; and (d) the turning of 
pigs into woodlands, forest plantations, and the like, where the June 
beetles conceal themselves by day. 
These are all measures calling for codperative action by all or at 
least the greater part, of the farmers of a neighborhood, since it is use- 
