The principal modes of fighting insects may be classified under three heads; modes of culture, barriers to progress, and topical applications. The modes of culture may be directed either to the destruction of the insect, or to the support of the plant under insect injuries, enabling it to rally against them. They are commonly the simplest, most convenient, and cheapest methods of controlling insect depredations, when they do really control, and should consequently be treated first. As a crop must be cultivated at any rate, if by varying slightly the times and modes of our culture we can take advantage of our insect enemies, this is, of course, to be preferred as a general rule to any method requiring special labor, apparatus and material.

The favorite method of strawberry culture in Illinois is that of growing the plants in rows, between which the ground is regularly cultivated for three years, after which the whole field is plowed up and reset with young plants. Of course, where this method is followed, if proper care be taken to set the ground again with plants free from noxious insects, few injurious species can make much headway; and if to these precautions we add that of taking measures to prevent the spread of insect enemies from an old field to a new one, we should certainly have the matter pretty well under control, as far as those species are concerned which pass their whole lives during all their stages in the strawberry field.

As an example of the use of barriers to progress, we may refer to the practice of opening new fields at a distance from the old, in order to prevent the passage of the crown-borer from one to the other-a practice to which I shall again refer farther on, while topical applications may be illustrated by the use of Paris green on the vines, or even the fire cure, as applied for the leaf-roller.

Little can be done for the direct destruction of insect enemies until the fruit is picked, unless it be the hand picking of grubs and cutworms, where they are very numerous, or the use of harmless insect poisons, like pyrethrum, for some of the minor larvæ which may perhaps require attention. In June, after the crop is harvested, some things may well be done. The field may be mowed, covered lightly with

straw if necessary, and fired when dry, thus destroying the leaf-rollers, and probably the plant-lice also, and perhaps the strawberry worms, and the eggs and larvæ of the Angerona and of the "smeared dagger." Some other insects would probably likewise be exposed to extermination at the same time by these means.

The summer months (June, July and August), are the proper ones for the application of poisons, which will take effect at this time upon the strawberry worm, some, at least, of the leaf-rollers, the Angerona (if it should happen to be in the field), and the beetle of the root-worm. Some other species, less common and destructive, would probably also be reached if present.

If, as is not unlikely in a badly infested field, such measures as the above are found after all ineffective, and the strawberry farmer finds himself reduced to the last desperate expedient of destroying the plants and their enemies together, he should carefully study the calendar in order to determine at what season the greatest number of the species actually infesting his fields may be exterminated by that means. At whatever season the plowing is done, if the ground is planted to another crop the following year, the crown-borer will be destroyed, since its feeble migratory power will not enable it to save itself by retreat. Still, plowing soon after berry-picking would most certainly effect the entire destruction of the brood, since at that time no adults are living, and few if any larvæ would be far enough advanced to transform in the dead crowns. Plowing in spring (March or April) would probably destroy such cutworms as occurred in the fields; would certainly exterminate the plant-lice, which at this time would be found upon the crowns, either as eggs or newly-hatched young; and would probably kill the crown-miner also, which is at this time still in the crown, lacking some weeks of its full development. The strawberry worm, however, being imbedded in the ground, prepared for its final transformation, would not now be injuriously affected. Neither would the leafroller nor the smeared dagger, nor the root-worm, nor the white grub, nor the larva of the goldsmith beetle, be pre

vented from completing their development. True, these insects on emerging would find no breeding places in the field, but this fact would simply force them to scatter to other situations, thus transferring, but, perhaps, scarcely mitigating their attack. If plowing be postponed until September or October, the crown-miner would doubtless be destroyed, and many, if not all of the root-worms, would be prevented from reaching maturity, especially if the field were plowed early in the first month mentioned or late in August. At this time, also, the young white grubs hatched from the eggs laid in June and July would perhaps also perish, and the plantlice, collected upon the crowns, would share the same fate. If it be desired to exterminate the crown-borer and the root-worm without changing ground and without alternation of crops, I see but one way in which this can be done. If the vines are thoroughly treated with Paris green or some other equally effective insect poison from the middle of June to the middle of August, when the beetles of the root-worm are on the leaves, there will probably be little trouble from these worms the following year; and if on this next year the field be plowed up immediately after picking, it will be impossible for the crown-borer to survive until the following spring, when I believe that the ground may be safely reset.

But I need not ring the changes on all possible methods of treating the field at each season of the year, as, with such an insect calendar as that herewith given before him, every intelligent fruit-grower, knowing the species with which he has to deal, can decide for himself what measures are best suited to meet existing conditions.

I will add only a few words on the establishment of new plantations in a way to escape infection by insects from old fields. Of course two points are to be considered; first, that of securing young plants free from noxious insects in any stage, and second, that of guarding the newly-planted fields from invasion. Here, again, everything depends on the insects occurring in the field. If it is the strawberry worm or the cutworm, or the root-worm, or the white grub which is to be guarded against, the young plants may be taken up any

time before April, but every care must be taken that none of the hibernating larvæ or pupæ are transferred among the roots. If the field should happen to be infested by the crownminer, only the stools which formed in autumn would be certainly free from this pest, and the difficulty of distinguishing these from those of earlier growth, which might consequently contain the eggs of the moth, would make it imprudent to take young plants from a field where the insect was known to occur. Substantially the same remark must be made respecting the leaf-roller. Unless the field has been fired the previous year, all leaves of stools forming earlier than August will be liable to harbor the hibernating pupa, and it is prudent to get plants for a new stand elsewhere.

Concerning the crown-borer it is safe to say that the earlier in spring plants intended for setting can be removed from a field previously infested by this insect, the less will be their liability to contain the seed of future generations of this most destructive pest. If it is the strawberry plant-louse which we wish to exclude, the case is still more difficult. As already noted, this insect occurs on the plants either as egg or female, at every season of the year, and no security can be had against transferring it unless the plants be dipped, before setting, in some insecticide which will destroy both the lice and eggs. I know of nothing more likely to effect this than the kerosene emulsion, the use of which for horticultural purposes has been so widely and emphatically recommended by Prof. Riley.

For the protection of the new fields from invasion, I know of no resource but isolation. Either the entire plantation should be renewed at once, with proper precautions to destroy the insects existing, so that no old fields will remain to infect the new, or else fields of different ages should be separated from each other by areas devoted to other crops. If one grows raspberries and strawberries both, for example, and wishes so to manage his strawberries that he shall have about equal areas in bearing every year, the two crops might be arranged in alternating belts. If these belts were only a few rods wide, the spread of the crown-borer from patch to

patch would probably be prevented, and the other insects can be managed by other methods.

To summarize in a word what may be done, according to the best of our present knowledge, in the case of our hypothetical field infested by all known strawberry insects, I I would say that we shall have to depend chiefly on insect poisons in June and July, and on burning in June, to exterminate all insects but the crown-borers, and that to rid the plants of these, we must plow up the field in the following June, resetting with young plants as early as possible in the spring. If the field is not exposed to immediate infection from others near by, we have fair reason to believe that these measures will be found efficient against the insects affecting the strawberry.