52 NATUBAL CONTROL OF WHITE FLIES IN FLORIDA. 
preference of the grower and the amount of work to be done. The 
compressed-air sprayer has a capacity of 3 gallons, and besides having 
the advantage of being somewhat lighter has a valve by the use of 
which the spray can be instantly cut off by the operator, thus pre- 
venting loss of solution in passing from tree to tree. It has the dis- 
advantage of requiring frequent pumping up, and having been in use 
for some time, this feature is apt to become a serious drawback. 
Knapsack sprayers and barrel pumps, new or thoroughly cleaned, 
were found less likely to cause delays in work. 
The method of procedure in the grove has differed but little from 
that by which insecticides are applied, and is very simple. In using 
knapsack or compressed-air sprayers it has been found very conven- 
ient to have as many jars on hand as there are sprayers. After the 
fungous leaves have been shaken the solution is strained directly into 
the tank and then diluted to its capacity. The jars are then refilled 
with another supply of leaves and water and allowed to stand until 
the contents of the first tank have been sprayed out. After the first 
shaking, the leaves have been used to advantage a second time when 
the supply was limited, but when an abundance of fungous leaves 
was available it was found to be a better policy either to throw them 
away or add fresh leaves for reasons mentioned elsewhere. Where 
three or four sprayers were in use it was found to be of advantage 
to have an additional man to keep the water supply replenished, 
shake the fungus, and change the base of supplies, so as to save time 
in traveling back and forth. 
When using a barrel pump, in view of the larger amounts of water 
necessary, it is more essential that the tub or other retainer be placed 
near a larger supply of water. After the spore solution had been 
prepared and strained into the barrel, the latter was filled and the 
solution sprayed. Meanwhile the tub was again partially filled and 
more leaves added to soak and be stirred in readiness for the next 
barrelful of solution. 
In spraying with knapsack or compressed-air sprayers, or in brush- 
ing, best results were obtained by directing the spray onto the under- 
side of the leaves of the outer, more heavily infested, shoots. 
Experiments have shown that better infections were obtained on the 
outer portions of the tree than on water shoots. With a barrel 
pump two leads of hose were used to advantage, the halves of two 
rows being sprayed as the wagon passed between the rows. 
The clipping method was first used as a check on experiments with 
other methods, but as it has been found to have a practical usefulness 
under some conditions, it has been frequently recommended by the 
authors to citrus growers. The water mixture is prepared as already 
described. A clean bucket half fuU of the unstrained mixture is 
held with one hand and arm in such a manner that with the other 
