146 REPORT OF THE BOTANICAL DEPARTMENT OF THE 
left in each field and these were treated with poison four times; 
yet in the seven-acre field bugs injured the unsprayed rows some- 
what more than the sprayed rows. The sprayer used was a Spra- 
motor one-horse, five-row power sprayer carrying thirteen nozzles. 
(Plate III, fig. 2.) The bordeaux was made with six pounds of 
copper sulphate and seven pounds of prepared lime to fifty gallons. 
The expense of spraying the eleven acres five times included the 
following items: 
258. Ibs copper zsulphate OG. ae, tits aeons wae ee $15.48 
301 OTM EHO VIC Regs Petes PO Rae Ae ee te 3.01 
40 “paris “greens (Gr bCe Gh ope a ee os ee 6.40 
6144- = “white carsenicX@ 8c: inn ton eee nc ciek ds Dee. he ee .52 
08. hrs. labor “for-man “@-i15c.42.1% e205 ee 14.70 
83 * labor fof. horse) Be, 2. ts ean e see ee 4.15 
Interest and wear on Sprayer.) eto -se cy ee eee II.00 
Lotalc. 225d spite eased so ya eee hae ee $55.26 
The total cost of spraying was $5.02 per acre or $1 per acre for 
each application. 
In both fields the unsprayed rows died somewhat earlier than the 
sprayed owing chiefly to the ravages of iate blight. Neither flea 
beetles nor early blight entered into the problem to any extent. 
The test rows in both fields were dug by hand October 4. The 
results were as follows: 
Seven-acre field—Five rows 477 feet long were left unsprayed. 
The yields in this field were as follows: 
Third sprayed row on the west, 372 lbs. marketable tubers. 
Third sprayed row on the east, 327 lbs. marketable tubers. 
Average of two sprayed rows, 349% lbs. marketable tubers. 
Middle unsprayed row, 28614 lbs. marketable tubers. 
Yield, sprayed, 177 bu. 19 lbs. marketable tubers per acre. 
Yield, unsprayed, 145 bu. 21 lbs. marketable tubers per acre. 
Gain, 31 bu. 58 lbs. marketable tubers per acre. 
There was a little rot on all of the rows and apparently no dif- 
ference between the sprayed and unsprayed. The yield of small 
and rotten tubers was 26 bu. 53 lbs. per acre for the sprayed and 
33 bu. 29 Ibs. per acre for the unsprayed. 
Four-acre field——There were four unsprayed rows 705 feet long. 
The yields in this field were as follows: 
Second sprayed row on the east, 532 lbs. marketable tubers. 
One of the middle unsprayed rows, 338 Ibs. marketable tubers. 
