

New York AGRICULTURAL EXPERIMENT STATION. 485 
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RESULTS OBTAINED BY SPRAYING WITH FUNGICIDES FOR THE 
PREVENTION OF Porato BLicut. 
On July ninth, before the appearance of blight, spraying experi- 
ments were started to note the effectiveness of the two best known 
and popular fungicides, viz., Bordeaux mixture and ammoniacal 
_ solution in their power to keep in check this disease. On that 
date an application was made of a mixture called liquid copper- 
dine, a manufactured article sent out by one of the leading fertiliz- 
ing chemists and claimed to be made from the United States 
Department formula for the ammoniacal solution. After using 
this mixture it was found by analysis that it was of but one-fourth 
the strength of the department formula and its further use on 
potatoes was discontinued and the ammoniacal solution of standard 
strength used in comparison with Bordeaux mixture. These 
remedies were applied with a Field Force Pump Company’s knap- 
sack sprayer, using a Vermorel nozzle to every alternate fifth row 
of potatoes, commencing at the first and third row, thus leaving 
every other row as check. This was done on a plat of White 
Star potatoes measuring six-tenths of an acre, the application 
being repeated at intervals of three weeks, with results as given in 
potato Table No. 1. By the middle of August almost every vine on 
rows not sprayed showed the effects of blight, while those sprayed 
either with Bordeaux mixture or ammoniacal solution were green 
and vigorous. At the time of harvest, the latter part of September, 
- each row that had received treatment could be plainly distinguished. 
On July thirty-first a square of thirty-six feet was staked off in the 
center of a quarter-acre plat of late planted potatoes, and the 
vines within the square sprayed with Bordeaux mixture three 
times at intervals of two weeks. By the middle of August the © 
entire plat surrounding this square showed signs of blight, while 
the sprayed square continued growing. When the main crop of 
potatoes were harvested this plat was left in order to see how 
long the vines of the sprayed portion would resist the attuck of 
the fungus. On October sixth the sprayed vines had turned brown 
and died out but probably from natural causes, as no signs of 
mildew could be seen. The entite plat was then harvested, and a 
comparison of the yield of sprayed versus unsprayed vines made 
in the following manner, the sprayed square containing 288 hills: 
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