DEVELOPMENT OF TUBERS IN THE POTATO. 
19 
cance, so that the data present no conclusive evidence to show that 
the weight of the tuber is de'pendent upon the length of the stolon 
which bears it. 
Table V. — Correlation between the length of each stolon and the weight of the tuber which it 
-produced in 55 hills of Charles Downing potatoes grown at Greeley, Colo., in 1918. 
[Coefficient of correlation, -0.112±0.052.J 
Weight of tubers (grams). 
Length of sto- 
lons (mm.). 
1 
to 
25 
26 
to 
50 
51 
to 
75 
76 
to 
100 
101 
to 
125 
126 
to 
150 
151 
to 
175 
176 
to 
200 
201 
to 
225 
226 
to 
250 
251 
to 
275 
276 
to 
300 
301 
to 
325 
326 
to 
350 
351 
to 
375 
376 
to 
400 
401 
to 
425 
426 
to 
450 
Fre- 
quency. 
1 to 25 
2 
1 
1 
3 
1 
2 
.... 
"K 
1 
2 
1 
I 
1 
5 
5 
2 
1 
3 
7 
5 
5 
8 
7 
1 
3 
6 
4 
2 
1 
1 
4 
5 
*3" 
2 
] 
2 
2 
2 
"3" 
1 
2 
1 
1 
2 
1 
.... 
1 
2 
1 
2 
1 
1 
27 
26 to 50 
1 
1 
1 
2 
1 
1 
2 
29 
51 to 75 
2 
"2 
1 
2 
28 
76 to 100 
1 
1 
35 
101 to 125 
126 to 150 
"2 
.... 
19 
9 
151 to 175 
1 
1 
1 
1 
1 
........ 
10 
176 to 200 . . . 
3 
201 to 225 
1 
226 to 250 

251 to 275 . 

276 to 300 . . . 
1 
1 
301 to 325 
I 
36 
1 
Frequency. 
7 
11 
11 
18 
...... 
18 
15 
13 
6 
6 
6 
3 
4 
4 

3 
~ 
1 
163 
A further study of the data for the purpose of ascertaining whether 
the length of the stolon and the size of the tuber are associated with 
a definite position on the stem, included a grouping of the plants 
having two, three, and four stolons, respectively, using only those 
in which one tuber was produced at each node. The summarized 
results are shown in Table VI. 
Table VI. — Relation of the position of the stolon on the stem to the length of each stolon 
and the weight of the tuber which it produced, in 55 hills of Charles Downing potatoes 
grown at Greeley, Colo., in 1918. 
Position of the stolon. 
Number 
of hills. 
Length 
of the 
stolon. 
Weight 
of the 
tuber. 
Two stolons per hill : 
Lower stolon 
18 
18 
14 
14 
14 
10 
10 
10 
10 
Mm. 
66.2 
68.0 
45.4 
55.2 
106.6 
71.4 
89.1 
90.4 
110.2 
Grams. 
210.3 
Upper stolon 
175.4 
Three stolons per hill: 
Lower stolon 
179.1 
Middle stolon 
126.1 
Upper stolon 
127.9 
Four stolons per hill: 
Lower stolon 
119.4 
Second stolon 
138.0 
Third stolon 
120.5 
Upper stolon 
92.5 
It will be seen that while the original tabulations (Table IV) show 
considerable fluctuation, the averages brought together in Table VI 
indicate very consistently a high degree of relationship between the 
position of the stolon and its length, the shortest stolons being 
