INJURIOUS INSECTS OF I909Q AND I9QIO. [43 
ORCHARD AND GARDEN SPRAYING. 
Introduction. 
The following article on “Orchard and Garden Spraying”’ is the 
result of the collaboration of A. G. Ruggles of the Division of En- 
tomology, and E. C. Stakman of the Division of Plant Pathology. 
Its appearance at this date is timely, and there is much demand for 
the information contained therein. 
By the up-to-date orchardist spraying is considered as essen- 
tial as any of the other processes necessary to the production of 
good fruit. It is regarded in much the same light that insurance 
is to the householder. Without spraying one runs the risk of con- 
siderable loss. To spray intelligently one should know just what 
he is spraying for, and it is nearly always essential that he should 
know at least the main features of the life history of the pest 
sprayed against, be it insect or disease. In the following pages 
we have endeavored to give brief life histories, and thus show the 
reason for spraying with such and such a compound in each case. 
Very often we can advantageously use a fungicide at the same time 
we use an insecticide. It is advisable to do this wherever possi- 
ble. In fact, when spraying against a known insect, it is always 
good policy to combine even if not absolutely sure of the disease to 
be sprayed against. Sometimes, as with the lime-sulphur washes, a 
spray is both an insecticide and a fungicide. Arsenate of lead has 
a small fungicidal value, and when added to the lime-su!phur wash 
this fungicidal value is increased. 
A few precautions are perhaps necessary, viz. : 
1. Never spray when the trees are in bloom. A day’s delay at 
this time will not materially affect the result of the spray. Bees 
and many other insects are very numerous at this time, fertilizing the 
flowers. A spraying compound thrown on them will lessen the 
amount of fruit set and destroy the honey bees. 
2. Sprays recommended for the dormant season should never 
be tried when the trees are in leaf. 
Before taking up the insecticides and fungicides in detail a gen- 
eral idea of the use of these killing-compounds may be desirable. 
