27 
good, no Phytoplitkora being visible anywhere. There was, however, a blight of 
the foliage that has proved very general and widespread throughout all this region. 
The leaves turned yellow in spots, then brown, and the entire vines died long before 
the growing season was completed. The check rows in the experimental plat and 
my own potatoes elsewhere on my farm were all seriously alfected with this blight. 
By the first of September this was so emphatic that the check rows were easily 
selected from the plat, the treated vines showing mostly bright and green when frost 
came. Still there was an occasional hill among the treated vines showing the same 
trouble as the untreated, but not in so large a degree. 
We had expected to use our field pump in a large barrel mounted on farm trucks 
with the Vermorel nozzle attached to the hose, but found that we could not go over 
the plat and make the turns with the team without running into the potatoes and 
injuring them. So we abandoned its use and did the entire work by hand with our 
Nixon Climax pump, using a No. 3 Nixon nozzle. We overcame the difficulty of 
clogging by having a piece of brass wire strainer cloth soldered over the lower end 
of the suction pipe. This had a mesh finer than the orifice of the nozzle and was a 
complete remedy for clogging, not only in using the Bordeaux mixture, but also in 
all other spraying done by us. 
Another variation we made was in using the Bordeaux mixture. We hauled out 
for each treatment a barrel containing 12 pounds each of copper sulphate and lime 
and 44 gallons of water properly mixed to make the regular Bordeaux mixture. 
We also took another barrel of clear water. At the beginning we stirred the mixture, 
allowed it to settle a minute, and took out two or three pailfuls to use. After using 
enough for the southwest corner, clear water was added to the large barrel, and so on 
until the plat was gone over, 70 to 75 gallons in all being used. This would give about 
the following strength nominally to each plat: Southwest, full strength; southeast, 
two-thirds; northeast, three-fourths; northwest, one-half. There was, however, about 
the same appearance in the consistency of the liquid used for each plat on account of 
the sediment in each lot being about all the water would carry, and the appearance 
of the vines after spraying was the same in each plat. From the time of the first 
spraying the application was always more or less visible. I thought there was a 
difference in the vigor of the vines in favor of the northeast corner, but suppose the 
figures as tabulated by Professor Goff will show this matter clearly. At any rate I 
venture the opinion that it may be well to experiment with Bordeaux mixture in a 
more diluted form than the regular formula. 
Another apparent result of the spraying was in regard to the Colorado potato 
beetle. I found it necessary to go over the check rows with London purple the 
second time, but the treated part was almost eutirely free from them. It would thus 
appear that where the mixture is used for rot and blight it may also be efficient as an 
insecticide. 
DISEASES OF THE ORANGE IN FLORIDA.* 
By Lucien M. Underwood. 
The following notes on the diseases of the orange in Florida were 
made during a visit to that State during the months of February, March, 
and April of the present year (1891). They consist simply of the results 
of observations in the field and evidence collected from intelligent 
growers in various portions of the State. The orange groves and 
methods of cultivation and treatment were observed in the following 
counties: Brevard, Citrus, Hernando, Lake, Manatee, Marion, Orange, 
* Professor Underwood collected the information embodied in this report while act¬ 
ing as special agent for the Division of Vegetable Pathology.—[B. T. G.] 
