28 Nebraska Agricultural Exp. Station, Research Bui. 7. 
When heavy seed production is prevented and when tempera- 
ture, moisture, etc., are kept fairly uniform, retardation of growth 
can be avoided for a long time, if not indefinitely. In Figure 12 
are shown growth curves of three plants of the same inbred strain 
of a race of very small pole beans, Snowflake (Navy or Pea bean). 
A and B were from seeds of the same selfed plant and C was 
directly related to them. Under the somewhat unfavorable 
conditions in the garden during a hot and rather dry summer 
(Fig. 12C), growth was at no time very rapid. The heavy setting 
of pods and increasingly unfavorable weather caused a marked 
retardation of growth at about the twentieth node and at the 
height of about 1 meter. With the more favorable temperature 
and humidity and somewhat deficient light of the greenhouse 
(Fig. 12B), growth was rapid at first but the development of a 
considerable crop of pods and the deficiencies of the soil — about 
1.5 liters of a poor sandy loam — brought about an early retard- 
ation of growth at about the fifteenth node and at a height of 1.5 
meter. Under the same favorable atmospheric conditions, with 
the advantage of abundant soil fertility — about 10 liters of rich 
loam- — and without the drain of heavy pod production, a sister 
plant (Fig. 12A) kept up a remarkably uniform growth to near 
the thirtieth node and to a height of four meters when the ex- 
periment was discontinued. 
100 
90 
80 
70 
60 
50 
40 
30 
20 
10 
0 
r 
0 
0 
460246024 
Internode numbers. 
Fig. 13. — Growth curves of (A) and (B) medium tall bush beans, Red Marrow, 
2,423 (B) and 2,423 (f), and of (C) and (D) short bush beans. Triumph, 
2,422 (A) and 2,422 (f). Plants (A) and (C) were grown in large pots 
of rich soil and plants (B) and (D) in small pots of poor soil. 
