‘ 
New York AGRICULTURAL EXPERIMENT STATION. 175 
size of the tubers. There was no rot worth mentioning on either 
the sprayed or unsprayed plants. 
The market price of potatoes at digging time was 50 cents 
per bushel. ; 
EXPERIMENT NO. 41. 
Conducted by Charles B. Foster, Water Mill, Long Island. Ten 
acres of potatoes, Carman No. 1, were sprayed twelve times with 
a Schanck sprayer. About one-half acre was left unsprayed. 
The items of expense were as follows: | 
362 pounds copper sulphate, at 534c.................. $20 82 
Paepounds copper sulphate, at TC.-5 0. ioe 6 cle sepa ore « 28 00 
Pea ee RTECS, Ap LSI) oot ae oedo! drags’ + g's dime ove acer e hens 5 55 
Prerncuresiapor foreman, at Lt5oc.. 2.5... ee etek see 18 90 
Pasncurslapor tor horse, At 10 06. ee ae ceiee ee ce 5 40 
Bemis SoOariscOTCCU, AL LOC, ae we cantas Ge ece shen nea ee = 7 80 
Peer Ma TST SEL VQ a9e cies Gia 620 sik S13 ales agence: Ans & <is pamsaus flee se 4 00 
ea A Sheen i io REE oS yeeiS 4 Fin > Gi eaete Visors ne ets yaadhe Rosas $90 47 
An unsprayed row 26 rods long, 34 inches wide, yielded 383 
pounds or at the rate of 228 bushels 45 pounds per acre, while 
a nearby sprayed row yielded 518 pounds or 309 bushels 23 pounds 
per acre, making a difference of 80 bushels 38 pounds of market- 
able tubers per acre in favor of spraying. 
Contrary to the usual experience there was more rot on the 
sprayed than on the unsprayed rows. Mr. Foster estimates the 
loss from rot at 40 bushels per acre on the sprayed areas and 15 
bushels per acre on the unsprayed. The explanation of this 
seems to be that the weather conditions most favorable to rot 
came after the unsprayed plants were dead and dry and the blight 
spores mostly dead. The sprayed plants, on the contrary, were 
still green and covered with live spores of late blight which, 
falling upon the ground, caused the tubers to rot. In this part 
of Long Island late blight was particularly severe. In spite of 
thorough spraying the disease made steady progress and caused 
considerable damage. When we saw this experiment on August 
10 the unsprayed rows were entirely dead while the sprayed 
rows retained about three-fourths of their foliage. Mr. Foster 
