NEw York AGRICULTURAL EXPERIMENT STATION. 95 
of copper sulphate was used with the soda bordeaux. It was 
made by the formula, six pounds of copper sulphate, nine pounds 
of sal soda and fifty gallons of water, while the lime bordeaux 
was made with four pounds of copper sulphate, five pounds of 
lime and fifty gallons of water. These results should not be con- 
sidered conclusive proof of the superiority of soda bordeaux. 
In more thorough tests made at the Experiment station soda 
bordeaux proved inferior to lime bordeaux.'° 
Combining the results obtained in the two tests we have an 
average gain of 19 bu. 26 lbs. per acre, worth, at forty cents per 
bushel, $7.77. Subtracting $2.85, the expense of spraying, there 
remains a net profit of $4.92 per acre. 
THE OGDENSBURG EXPERIMENT. 
This experiment was conducted by Andrew Tuck, Ogdensburg, 
N. Y. It included two fields of potatoes, one of 4 acres and 
another of 2% acres. In both fields the surface drainage was 
good and the soil a sandy loam. ‘The variety of potato was Rural 
New Yorker No. 3. The smaller field was planted May 29 and 30 
and the larger one June 12 and 13. 
Both fields were sprayed with bordeaux mixture five times,— 
July 18, 25, August 13, 20 and September 4. The sprayer used 
was a new style Aspinwall potato sprayer drawn by one horse. 
Four rows were covered at each passage with one nozzle per row. 
The bordeaux mixture was made with six pounds of copper sul- 
phate to fifty gallons of water and sufficient lime added to satisfy 
the litmus paper test. Water was obtained from a nearby well. 
An unsprayed strip of three rows was left in each field. These 
rows were kept free from “bugs” by four applications of paris 
green in lime water. On the sprayed portions of both fields paris 
green was used with the bordeaux mixture in the first four 
sprayings at the rate of from two to four pounds to fifty gallons 
of bordeaux. During the season sixty-four pounds of paris green 
were used on the 6% acres. This free use of paris green was 
the cause of the expense running so high in this experiment. 
Both early and late blight were factors in this experiment. 
During the first two weeks in September there was considerable 
contrast between the sprayed and unsprayed rows owing to the 
greater amount of blight on the latter. 
1 See N. Y. Exp. Sta. Bul. 264:187; and Bul. 279:215. 
