BROOKLYN BOTANIC GARDEN 
LEAFLETS 
THE BROOKLYN INSTITUTE OF ARTS AND SCIENCES 
Series V Brooklyn, N. Y., May 16, 1917. No. 6 
SOME INSECT PESTS* 
INTRODUCTION 
The successful control of injurious insects which affect plants 
depends largely upon the application of preventive or remedial 
measures at the right time. For instance: San Jose Scale is best 
controlled by spraying in fall or early spring; apple trees liable 
to attack by Codling Moth must be sprayed as soon as the blos- 
soms fall, when the calyx cups are in an upright position and will 
retain the poison; and in all cases remedial measures must be 
applied at the earliest possible moment before the insects have 
had time to become numerous and firmly intrenched. Thus, in 
combating Aphids on fruit trees, spraying with lime sulphur 
(winter strength) before leafbuds open will destroy many of their 
eggs, and a nicotine or soap spray when the leaves are unfolding 
(April 27th to May 1st) will take care of the first brood and prob- 
ably prevent a serious attack later in the season. It is much 
easier, and better, to kill a few insects before they have done 
much damage than it is to get rid of a large number when they 
have probably done serious injury to the trees or plants attacked. 
If it is possible to control the pests by spraying, it is neces- 
sary that the right kind of spray be used, or, if spraying is of no 
avail, one must know what measures to take to prevent damage. 
In the first place, it is important to know whether we are dealing 
with “biting” or “sucking” insects. The former group— those 
which bite or chew their food — can usually be dealt with by pois- 
oning their food with an arsenical spray of some kind, arsenate 
of lead or Paris green being most commonly used. Obviously 
this kind of treatment can only be successful when the insects 
feed openly. If they feed in such a manner that it is not possible 
to poison their food, other methods must be adopted. These may 
take the form of some change in horticultural practice, such as 
♦The Botanic Garden is indebted, through Dr. W. E. Britton, to the Connecti- 
cut Agricultural Station, for the cuts illustrating this Leaflet. 
