156 REPORT OF THE BOTANICAL DEPARTMENT OF THE 
The dates of spraying the test rows were June 26, July 6 and 
August 7. Paris green was applied only in the first spraying and 
the unsprayed rows were treated with poison on the same date. 
Test No. 1—The rows in this test were 874 feet long. They 
were dug September 27 and the following yields obtained: 
Second and third sprayed rows on the north, 1,287 lbs. marketable tubers. 
Second and third sprayed rows on the south, 1,329 lbs. marketable tubers. 
Average yield for two sprayed rows, 1,308 lbs. marketable tubers. 
Middle two unsprayed rows, 1,104 lbs. marketable tubers. 
Yield, sprayed, 197 bu. 30 lbs. marketable tubers per acre. 
Yield, unsprayed, 166 bu. 42 lbs. marketable tubers per acre. 
Gain, 30 bu. 48 lbs. marketable tubers per acre. 
The yield of culls was at the rate of 10 bu. 12 lbs. per acre for 
the sprayed and 16 bu. 18 lbs. per acre for the unsprayed. There 
was a little rot on the sprayed rows, but somewhat more on the 
unsprayed. 
Test No. 2.—Here, the test rows were 674 feet long. The 
sprayed rows on the north were given three sprayings as in Jest 
No. 1, but those on the south received only two sprayings—June 
26 and July 6. The test rows were dug September 27 with the 
following results: 
Second and third sprayed rows on the north, 604 Ibs. marketable tubers. 
Second and third sprayed rows on the south, 637 lbs. marketable tubers 
Average yield for two sprayed rows, 62014 lbs. marketable tubers. 
Middle two unsprayed rows, 420 Ibs. marketable tubers. 
Yield, sprayed, 126 bu. 35 lbs. marketable tubers per acre. 
Yield, unsprayed, 85 bu. 41 lbs. marketable tubers per acre. 
Gain, 40 bu. 54 lbs. marketable tubers per acre. 
The yield of culls was 14 bu. 47 lbs. per acre for the sprayed 
rows and 5 bu. 12 lbs. per acre for the unsprayed. On the sprayed 
as well as the unsprayed rows there was considerable loss from 
rot. 
Why the rows on the south, sprayed only twice, yielded more 
than those on the north which were sprayed three times is not 
known. Mr. Burke states that on the whole the portion of the field 
sprayed twice (about four acres) did not yield as well as the por- 
tion sprayed three times. 
Combining the results obtained in the two tests the average gain 
due to spraying in this experiment is 35 bu. 51 Ibs. per acre. At 
