146 The Philippine Journal of Science 1921 
& 
It is unfortunate that plats of uniformly susceptible varieties 
could not be employed ; but, as stated previously, there were no 
such mature orchards in the Philippines. 
The trees, except in a few instances, were in good growing 
condition, planted in orchard formation on level, clean-cultivated 
land. The trees were for the most part five years old at the 
beginning of the experiment. The orchards were surrounded 
by dense thickets of bamboo, 10 to 14 meters high, and these 
bamboo thickets formed very efficient windbreaks. 
All plats at Lamao underwent entirely the same treatment 
in regard to irrigation, fertilization, and cultural operations. 
Only treated plats underwent pruning, and no pruning of the 
control plats was made. 
All spraying mentioned here was carried on with a hand-power 
pump equipped with a pressure tank, and all spray applications 
were made with the pressure maintained at from 120 to 140 
pounds. Operations for the removal of infected parts and the 
stimulation of new growth were identical in all the treated plats. 
The detailed reports will not be presented from all of the 
plats, in as much as the general conclusions from each plat 
were much the same. Several of the plats, however, contained 
varieties, the susceptibility and resistance of which may be of 
interest in America; these plats have been selected for presen- 
tation not only to show the effect of the canker-control methods 
but also to show comparative susceptibility. 
PLAT I, ORCHARD A, LAMAO 
September 3, 1917. Lime sulphur (32° Baume) 1-40 solution. 
September 20, 1917. Bordeaux 4-4-50 mixture. 
September 21, 1917. Trees pruned for twig cankers. 
October 23, 1917. Bordeaux 4-4-50 mixture. 
November 20, 1917. Formalin 1-80 solution. 
November 21, 1917. Trees pruned for twig cankers. 
November 28, 1917. Lime sulphur 1-50 solution plus formalin 1-100, 
and powdered, neutral lead arsenate to make 1-50 mixture. 
December 7, 1917. Kerosene-lysol emulsion, plus formalin 1-70. 
January 10, 1918. Neutral Bordeaux mixture plus resin, sal-soda 
sticker and formalin 1-100. Trees carefully pruned for twig 
cankers. 
May 31, 1918. Lime sulphur 1-40 solution. 
June 25, 1918. Neutral Bordeaux mixture plus kerosene-lysol emul- 
sion, plus formalin 1-100. 
August 1, 1918. Lime sulphur 1-35 solution. 
The condition of the trees in regard to canker may be followed 
through the different seasons in Table 9. 
