New YorK AGRICULTURAL EXPERIMENT STATION. 245 
INTRODUCTION. 
Does it pay to spray potatoes in New York? Potato growers 
have been asking this question for fifteen years or more. It is 
well known that in seasons when blight is destructive spraying will 
check the blight and considerably increase the yield; but the ma- 
jority of potato growers have doubted that spraying is profitable on 
the average. They argue that blight does not appear every year. 
In some seasons it causes but little if any damage, yet the spray- 
ing must be done regularly because it is impossible to foretell the ap- 
pearance of blight. The result is that in some seasons spraying is 
profitable while in others it is unprofitable; and these growers doubt 
that the aggregate gain in yield for a series of years will more than 
pay the expense of annual spraying. 
This Station has set out to find an answer to the above ques- 
tion. The investigation was begun in 1902 and is to be continued 
until 1912. During ten consecutive years numerous potato spray- 
ing experiments will be made each year and at the end of the period 
the results will be averaged. The experiments are of three kinds: 
(1) Station ten-year experiments; (2) farmers’ business experi- 
ments; (3) farmers’ volunteer experiments. The ten-year ex- 
periments (two each year) are carried out entirely by the Station. 
The business experiments (13 to 15 each year) are conducted by 
farmers in co-operation with the Station. The volunteer experi- 
ments are carried out entirely by farmers. 
Bulletins previously published are: 
No. 221. Potato Spraying Experiments in 1902; 
No. 241. Potato Spraying Experiments in 1903; 
No. 264. Potato Spraying Experiments in 1904; 
No. 279. Potato Spraying Experiments in 1905; 
No. 290. Potato Spraying Experiments in 19006. 
SUMMARY OF RESULTS OBTAINED IN TEN-YEAR 
EXPERIMENTS PRIOR TO 1907. 
RESULTS IN. 1902. 
Tasle [.— YIELD BY SERIES AT GENEVA IN 1902. 
See 




SERIES. Rows.f ° Dates of spraying. Yield per acre.* 
Bu. lbs, 
FA 2 3; L4 ei andes laos ie tiialO, sa and Auptisy 12.4 245.0 .0 08 bees 317 41 
Ni ae 2.5: S andl, i lune. 25, July 10,23. 30, August 12,-26 and 
SHEE IIIOET TOG meee eR bod dae 2 aE ete oP 342 - 36 
ite. - Sera cil Pie. ota een Sire wets tein bes 2 ee Oe aig ly a ot de Ox 219 4 
ee eEEEeE—E——EE—E—E—EEE—E—E 
+ Rows 10, 11 and 12 omitted because of probable error. 
* The yields given in Tables I to X relate to marketable tubers only. } 
