I22 REPORT OF THE BOTANICAL DEPARTMENT OF THE 
A third line of effort has been the collection of the results of 
numerous volunteer potato-spraying experiments made by farmers. 
Fifty such experiments are reported in this bulletin. ‘lhe most 
important feature of these experiments, as a whole, is the increase 
in yield due to spraying. However, several of them contain other 
points of special interest. 
SUMMARY OF RESULTS OBTAINED IN TEN-YEAR EXPERI- 
MENTS PRIOR TO 1905: 
TABLE I.—YIELD BY SERIES AT GENEVA IN 1902.2 



SERIES. , Rows. Dates of spraying. Yield per acre 
Bu. Lbs. 
t Meets « 4 7and tS acme July 10; 23 andvAtie eo ase eee 317 41 
0B Reve aon ti eee DO msc alice & nate June 25, July 10, 28, 30, Aug. 12, 26 and 
Sept, TO. skicce cerrado ene Shee Tee 342 36 
PTT eee a 371070 anual ones ee Notusprayed:s crokiece eae a as. crete tis ee eee 219 4 


AS A A SN A SF RE EOS AA RE SE 8 SO IEE SIE OT ES TI TE rR SRT 
Gain due to spraying three times, 98% bu. per acre. 
Gain due to spraying seven times, 1234 bu. per acre. 
TABLE II.—YIELD By SERIES AT RIVERHEAD IN 1902. 





| 
SERIES. Rows. Dates of spraying. Yield per acre 
Buz. Lbs: 
eee Fs: 240 Scand Loe ae May.26,0} une? 20) ands) ahy-l 2 sucess 295 20 
s 8 ies Se ee Le As7candalOee, cree May 26, June 3, 20, 30, July 11, 23 and 
Aug. bs: caine OMG ae eee S12 35 
EDV ergs costo 3 OM Mere hats il AE ia he Not-sprayed 9... scat cinta tn eee 267 40 
D sa a SES oR SE EE ERS RE ES ES TS OTE ES SRS NRSC He SS SS 
Gain due to spraying three times, 27% bu. per acre. 
-Gain due to spraying seven times, 45 bu. per acre. 
TaBLE I[II.—YIELD By SERIES AT GENEVA IN 1903.3" 




SERIES. Rows. Dates of spraying.4 Yield per acre 
‘ae " Bu. Lbs 
b Bc 1457, 10and 13.05 =: italy 1.4528 and Angw26e0. vee eee 262 _— 
II. .4s%i.e) 2, 6,8, Wand 14. .°.| July 7, 21, Auc..7, 21 and Sept..3 eee 292 10 
TIT. 2s.) B85, OF 302 and 15 oss, (eNot sprayed: tciex eet Pe eee 174 20 


4 The dates of spraying in Table IV on page 263 of Bulletin 241 are inc orrect. 
Gain due to spraying three times, 88 bu. per acre. 
Gain due to spraying five times, 118 bu. per acre. 
* For details of the ten-year experiments in 1902 see Bulletin 221. 
*For details of the ten-year experiments in 1903 see Bulletin 241. 
