a handbook of the mosquitoes of north america - Systematic Catalog ...

68 MOSQUITOES OF NORTH AMERICA
may be used but preferably one that gives a fine mist-like spray.
In areas accessible to trucks, as along roadways, extensive nar-
row marshes, or swamps, the oil may be applied from an auto
truck having a tank and a pump driven by the engine of the
truck (Fig. 20). Such power driven spray outfits are in ex-
tensive use in orchards, parks, and woodland areas, to control
insect pests. They can easily be employed in anti-mosquito
campaigns. By the use of several leads of hose, and lengthen-
(Cowte;yj of the E. C. Brown Co., Roclacstcr,
. .
FIGURE Ig. A simple spray tank for
oiling operations. It holds three gal-
lons and can be carried with ease.
ing them, extensive areas can be covered in the minimum time.
Their use will depend entirely on local conditions.
Many other methods of applying oil have been tried and
some are in use. Streams, ditches and ponds have been treated
by placing barrels filled with oil and so constructed that a con-
stant drip reaches the surface. The oil is gradually carried on-
ward by the stream or spreads slowly over the surface. This is
not very satisfactory owing to the failure of the oil film to
penetrate the grassy margins, drift or flotage. Waste soaked