New York Agricultural Experiment Station. 231 



the andover experiment. 



Conducted by J. M. Greene & Son, on a field of 8.5 acres at 

 Andover, N. Y. Four rows were left unsprayed for a check. A 

 strip of four rows adjoining the check on either side was single- 

 sprayed with bordeaux five times (See diagram on next page). 

 The remainder of the field was double-sprayed five times. Messrs. 

 Greene were led to double-spray so much of their acreage because 

 of the results of an experiment which they made in 1910.^ 



In 1911 the spraying was done very nearly as in 1910. The 

 sprayer used was a two-horse " Watson " covering four rows at 

 each passage. One nozzle per row was used in the first three 

 sprayings and two nozzles per row in the last two sprayings. 

 Water for the preparation of the bordeaux was taken from a 

 spring about ten rods from the potato field. Owing to the absence 

 of bugs it was unnecessary to use any poison even on the check 

 rows. Flea beetles and blight, also, were almost entirely absent 

 and only a few rotten tubers were found at digging time. Ap- 

 parently, the plants suffered from nothing which spraying might 

 be expected to prevent. There was little if any contrast in ap- 

 pearance between sprayed and unsprayed rows. 



The items of expense were as follows : 



215 lbs. copper sulphate @ 5 cts $10 75 



•215 lbs. lime @ 1 ct 2 15 



Labor for man and team and allowance for wear of sprayer, 



• estimated 2 @ 80 cts. per acre for double-spraying 34 00 



Total $46 90 



Expense of making five double-sprayings, $5.52 per acre. 



Expense of making five single-sprayings, $2.76 per acre. 



The plants were killed by frost on September M. Had they 

 been permitted to complete their growth the sprayed rows would 

 probably have made a better showing. The small differences in 

 yield of the different test rows was due, probably, to something 

 else than spraying. This is shown by the fact that one of the 

 check rows outyielded the other by 44 lbs. or 19.8 bu. per acre. 



In the accompanying diagram the test rows^ are indicated by 

 dotted lines and followed by their rate of yield. 



1 Reported in Bui. 338 of this Station, pages 134-135, 



2 Messrs. Greene think lliis estimate rather high. It is unfortunate that an 

 actual record was not kept. 



3 The test rows were 540 ft. long by 3 ft, wide. 



