I 
INTRODUCTION 
15 
is that the nature of the spray is the essential factor for the 
success in spraying with Bordeaux mixture. The spray must 
be very fine and “ misty,” or smoke like ; a hanging “ mist ” or 
“ fog ” must be produced which drifts over and through the 
tree and deposits on the surface of the leaves excessively minute 
drops, which, when dry, give the parts of the tree which have 
been sprayed the appearance of being almost uniformly covered 
with a very thin bluish film or dust. Such a deposit of Bordeaux 
mixture is so intimately attached to the surface of the leaf or 
fruit that it does not readily wash off. 
In order to obtain the right kind of spray, attention must 
be paid to two points : (1) a special type of nozzle must be used, 
and (2) sufficient pressure must be obtained at the nozzle. If 
these two requirements are not fulfilled, the full benefit from 
spraying with Bordeaux mixture cannot be obtained. 
As regards the nozzle, the fact must be emphasised that a 
special type is required, which may be called the “ Bordeaux 
nozzle.” There is at the present time a considerable amount 
of spraying with Bordeaux mixture being done with unsuitable 
nozzles. This results not only in a waste of labour and 
material, but even in actual harm. 
It follows that because the spray of Bordeaux mixture must 
be “ misty ” and not jet-like, it must be carried close to the 
part sprayed. In the case of tall trees this necessitates the use 
of long bamboo “ extension rods.” The fact that tall trees 
cannot be sprayed with Bordeaux mixture by means of a jet- 
like spray sent up from the ground cannot be too strongly 
insisted upon ; to secure a fine “ misty ” spray which shall drift 
over and through the tree and deposit itself uniformly over the 
leaves, a “ Bordeaux nozzle ” at the end of a rod of sufficient 
length must be used. 
The mixture as used on root fungus of trees may be 
made stronger and merely poured on the ground. For 
leaf fungi it must be sprayed in as fine a mist as possible 
so as to reach both sides of the leaves, for it must not 
be forgotten that most leaf fungi attack the plant on 
the underside of the leaf. 
There are many spraying machines invented suitable 
for all sizes of trees or estates. For small lots like 
nursery beds we often use a simple bamboo squirt made 
of a joint of bamboo, with the septum at one end 
perforated, and a stick wrapped at the end in rag for a 
piston. This, though a very rough apparatus, can be 
