LIFE HISTORY OF TIMOTHY 
21 
early in April, when the plants were transplanted to a field plat. There were 
several leaves on each plant at the time it was transferred to the field. 
Group AS. — Seeds were sown in a field plat early in April, 1916. 
Group B-l. — The plants in this group were growing in a broadcast plat 
of timothy which had been sown in September, 1915. On December 10, 1918, 
a number of vigorous shoots with a comparatively large number of leaves, 
all of which were intact at that date, were selected for further observation. 
Since from 15 to 20 leaves had developed by December 10 on each one of the 
shoots included in this group, it is evident that these shoots must have 
developed from buds some time in the summer of 1918. ♦ 
Group B-2. — The plants in this group were growing in an old timothy 
meadow. The shoots were first observed November 11, 1915. On one shoot 
there were four and on the other there were five leaves in addition to the 
prophyllum. Apparently these shoots had grown from buds comparatively 
late in the season of 1915. 
Group B-S. — The plants used in this experiment were making a vigorous 
growth in cultivated row plats. On May 11, 1916, shoots on which there were 
from two to seven leaves were selected for observation. From the small 
number of leaves on each one of these shoots it is apparent that most, if not 
all, of them had developed from buds in the spring of 1916. 
The records of all shoots which were used in this experiment are 
presented in Table 9. 
Table 9. — Effect of length of the growing period on number of internodes in 
timothy shoots collected for study in the July following the time ichen they 
developed from seeds or buds 
Number 
of shoots 
observed 
Length 
of stems 
(inches) 
Average number of internodes 
Growth of shoots 
Total 
In pro- 
axis 
In hap- 
locorm 
and 
culm 
Shoots grown from seed: 
5 
8 
8 
3 
2 
7 
39.5 
38.1 
33.4 
38.3 
38.0 
38.9 
21.0 
17.2 
12.3 
28.3 
18.0 
10.1 
14.6 
11.7 
7.0 
21.3 
12.0 
4.3 
6 4 
Group A-2; seed sown approximately March X-.— 
5.5 
5 3 
Shoots grown from vegetative buds: 
Group B-l; shoots developed from buds in sum- 
7 
Group B-2; shoots developed from buds in au- 
6.0 
Group B-3; shoots developed from buds in spring. 
5.8 
The following conclusions are evident from the data which have 
been presented : 
The number of internodes sometimes varies to a great extent. 
There is a relatively small amount of variation in the number of internodes 
per shoot in those shoots which have developed during the same growing period 
and under approximately the same cultural conditions. Thus, in Group A-l 
the range in the total number of internodes per shoot was from 20 to 23 ; the 
total number of internodes per shoot ranged from 15 to 19 in Group A-2, and 
from 11 to 14 in Group A-3. 
The total number of internodes per shoot in a general way varies directly 
according to the length of the growing period. This is illustrated by the records 
of the shoots on the plants in Groups A-l and A-3. The plants in the former 
group were from seeds sown in September, and the plants in the latter group 
were grown from seeds sown early in April. On the shoots from seeds sown 
in September there was by the following July an average total number of 21 
internodes per shoot ; on the shoots from seeds sown in April there was an 
average total number of 12.3 internodes per shoot. 
VARIATION IN NUMBERS OF NONELONGATED AND ELONGATED INTERNODES 
The greatest variation in the numbers of internodes in shoots 
which have developed during growing periods of different lengths 
