4 BULLETIN 52, U. S. DEPARTMENT OF AGRICULTURE. 
been naturally infected. On March 10 the three panicles sprayed 
with spores showed minute dark spots. The control was clean. On 
March 21 the four panicles were removed from the tree. The control 
was still clean, while those sprayed with spores were conspicuously 
marked on the peduncles and pedicels. Those showing disease were 
placed hi a moist chamber, and in two days large quantities of 
anthracnose spores had oozed out from the infected parts. This 
experiment was repeated on two other occasions without variation, 
and the same results were obtained. 
Bessey x conducted inoculation experiments with this same organ- 
ism and writes as follows: 
Under Prof. Rolfs' s direction, before he severed his connection with the Subtropical 
Laboratory, inoculation experiments were begun, which have been continued, with 
some interruption, under my direction since I assumed charge of the laboratory. 
These have demonstrated that this fungus (Colletotrichum gloeosporioides) is the 
same one that causes the blossom blight, leaf spot, and fruit rot of the mango and 
avocado, the tear staining of the mango, and the leaf spots and fruit rots of various 
other plants. 
SPRAYING EXPERIMENTS IN THE SPRING OF 1912. 
It was hoped to determine two points- by means of these spraying 
experiments: (1) Is Bordeaux mixture effective in preventing infec- 
tion of the flower clusters and fruits, and (2) how frequently and at 
what times is it necessary to spray to get the best results ? 
Unfortunately for the success of the work, there are no large groves 
of mangos in Florida. However, the work was done on as large a 
scale as was possible, and certain results which will be emphasized 
in other parts of this paper stand out quite clearly. Bordeaux mix- 
ture was the only fungicide used, and it was made according to the 
3-5-50 formula in 1912 and the 4-6-50 formula 2 in 1913. The 
spraying outfit consisted of a 50-gallon barrel sprayer, half -inch hose, 
and 9-foot bamboo extension rods equipped with double Vermorel 
nozzles. The spraying was done under a pressure of approximately 
75 pounds to the square inch. With one exception, noted later, no 
spray injury was observed at any time, and this is significant, as just 
such conditions existed as might be expected to induce it, i. e.. the 
weather was moist and showery during the first three weeks in which 
the spraying was conducted. 
The experiments were carried on at Mr. Flanders's place, about 2 
miles north, and Mr. Roop's place, about 3 miles west, of Miami. 
THE EXPERIMENT IN THE FLANDERS GROVE. 
The manges' on the Flanders place consisted of a double row of the 
Mulgoba variety, each row containing 31 trees. They were divided 
i Bessey, E. A. Op. cir. 
2 This shows the proportion of copper sulphate (bluestone), lime, and water usod in the mixuvnes. 
