COF.OKADO ExPI'IIMMENT StATION 
;J2 
was used tlie differences are so small as to suggest that they are 
within the limits of error. 
^Hie comparisons of whole, halved, and quartered seed where seed i 
])ieces of the same size were used, show that the kind of seed had I 
]) tactically no influence on the number and weight of the tubers ^ 
l)i-oduced in the one-ounce group. In the two- and three-ounce | 
groups there was a decided falling off in tuber production per hill | 
where quartered seed was used. Within each group there was little 
difference in the per cent of marketable tubers. The yields of 
marketable tubers per acre, also the net yields after deducting the ' 
weight of the seed used, were, in all cases except one, largest where 
whole seed was used, with the yields from halved seed next in order. 
In the one-ounce group the slightly lower yield where the whole seed 1 
was used is believed to be due to so-called exper.'mental error, ^vhich 
is indicated by the almormally low’^ yield produced by tlie one-ounce ^ 
Avhole seed in the first series of this experiment. In the second series , 
the yield from the corresponding plot wms in line wdth those of the ! 
other groups. | 
COOPERATIVE EXPERIMENTS AT CARBONDALE, 
COLORADO I 
In 1916, in addition to the work which was carried on at the 
station with the different sizes of seed, an experiment was conducted 
on a field basis at Carbondale on the ranch of the Crystal River Land i 
Company, commonly knoAvn as the Sweet Ranch. The relatively cool I 
summers at this place resulting from the high altitude, which i 
exceeds 6,000 feet, coupled with the deep fertile soil of a fine sandy i 
loam type make conditions esi)ecially favorable for potato j)roduc- | 
tion. At the time of planting, the soil Avas in excellent condition | 
and the supply of moisture abundant. This favorable environment | 
undoubtedly reduced to a minimum the differences in value of the ! 
different kinds and sizes of seed so far as germination was con- I 
cerned. Tavo varieties Avere planted, the Russet Burbank and Peach- ' 
bloAA'. Two lots of seed Avere used for each variety, one groAvn on j 
a special seed plot, the other taken from the ordinary market stock, 
both of Avhich A\^ere grown on the ranch. Each plot consisted of one ■ 
roAV 600 feet long. The i‘oavs Avere 39 inches apart and the distance ^ 
betAveen hills Avas 15 inches. The series Avas not duplicated. The ( 
crop was planted May 19 to 22 and dug October 23 and 24. Some | 
difficulty Avas experienced in planting the hu*gei‘ sizes, i)articulVii‘ly ' 
the fiAm-ounce Russet Biu'bank seed. This may explain in part tbe 
falling off in the yield of this seed. ITnfoi’tunately 'tliis i)oiid (*an- i 
