250 REPORT OF THE BOTANICAL DEPARTMENT OF THE 
DIRECTIONS FOR SPRAYING. 
In general, commence spraying when the plants are six to 
eight inches high and repeat the treatment at intervals of 10 to 
14 days in order to keep the plants well covered with bordeaux 
throughout the season. During epidemics of blight it may be 
necessary to spray as often as once a week. Usually six appli- 
cations will be required. The bordeaux should contain four 
pounds of copper sulphate to each 50 gallons in the first two 
sprayings and six pounds to 50 gallons in subsequent spray- 
ings. Whenever bugs or flea beetles are plentiful add one to 
two pounds of paris green or two quarts of arsenite of soda 
stock solution to the quantity of bordeaux required to spray 
an acre. 
Thoroughness of application is to be desired at all times, but 
is especially important when flea beetles are numerous or the 
weather favorable to blight. Using the same quantity of bor- 
deaux, frequent light applications are likely to be more effective 
and conidia of Phytophthora, infestans, the potato blight fungus. It is 
not uncommon for this fungus to attack the foliage and fruit of tomatoes 
in the open, but its occurrence on tomatoes under glass seems to be rare. 
The fact that potatoes were so generally free from Phytophthora during the 
summer of 1908 lends additional interest to the case. Accordingly, one of 
the writers visited Clyde for the purpose of looking into it. 
Mr. Miller stated that the tomato seed had been sown in June in a garden 
close beside a patch of potatoes. Here, the young tomato plants grew until 
some time in August when they were transplanted into the greenhouse. 
Mr. Miller did not notice whether the potatoes were affected with blight. 
Neither did he observe anything wrong with the tomato plants at the time 
of removing them to the greenhouse. In November some of the fruits began 
to rot. The trouble started in one corner of the greenhouse where the tem- 
perature was often lower than it should have been. The loss was small. 
yet there were always to be found a few rotting fruits. At the time of our 
visit (Dec. 15) only traces of the disease were to be found on the leaves, but 
affected fruits were common. Green fruits of all ages were attacked and, 
occasionally, fruits nearly ripe were affected. The fruits were variously 
marked with a conspicuous brown discoloration in the flesh. Many of the 
affected fruits showed no fungus on the surface; some, particularly those in 
an advanced stage of decay, bore molds of various kinds; while a few showed 
the fructification of Phytophthora which appeared as a delicate white mold. 
If we assume that P. infestans produces no resting spores, the conclusion 
is inevitable that the tomatoes contracted the disease from the potatoes 
while growing beside them in the garden. 
13 Copied from Bulletin 290, p. 320. The experiences of the past season 
do not warrant any material alteration in the reenmmendations there made. 
