34 
BULLETIN 1450, U. S. DEPARTMENT OF AGRICULTURE 
records are presented in Table 13 there were either five or six green 
leaf blades ; a few had four or seven ; only one shoot had as many as 
eight leaves with green or partially green leaf blades. 
Table 13. — Number of leaves with entirely or partially green blades on differ- 
ent groups of nonelongated timothy shoots at different times during the 
growing season 
Date shoots were observed 
Number 
of shoots 
from which 
records 
were 
obtained 
Average 
number of 
leaves per 
shoot with 
entirely or 
partially 
green 
blades 
Apr. 18, 1914 
May 2, 1914 
Aug. 30 to Sept. 1, 1916 
Oct. 16,1916 
Nov. 7, 1916. 
Nov. 30, 1918 
Dec. 7, 1918 
6.6 
5.6 
5.7 
5.2 
5.5 
4.7 
5.6 
Soon after June 1, when the internodes of the culms of fertile 
timothy shoots are making their most rapid growth in length, the 
number of green leaves begins to decrease. About the time when 
the seeds mature all of the leaves have become dry. The decrease 
in the amount of green-leaf tissue is actually somewhat more rapid 
than is indicated in Table 14, for the reason that the proportion of 
entirely green leaf blades to partially green leaf blades gradually 
diminishes. On the 14 shoots referred to in Table 14, on May 8, 80 
per cent of the growing leaves had entirely green blades ; on July 10 
only 28 per cent of the growing leaves had blades entirely green. 
On sterile shoots the leaf blades do not dry up nearly so rapidly 
as on fertile shoots. In one meadow examined August 5, 1922, it 
was found that on each one of the sterile shoots there were, as a rule, 
from three to five green leaf blades ; whereas, in the same meadow on 
a large percentage of the fertile shoots there were no green leaf blades 
at that time. Although a considerable proportion of the sterile 
shoots in any meadow usually cease growth, especially if the weather 
becomes very dry, during the latter part of the summer, on many of 
them green leaves continue to develop until growth is terminated by 
cold weather in late autumn. 
Table 14. — Average number of leaves with blades entirely or partially green 
on 14 elongated fertile timothy shoots at intervals of one iceek during the 
spring and early summer of 1916 
Date observed 
Average 
number of 
green leaf 
blades per 
shoot 
Date observed 
Average 
number of 
green leaf 
blades per 
shoot 
May 8 
6.7 
6.0 
6.0 
6.2 
5.5 
4.9 
June 26 ... 
3.9 
May 15 
July 5 
3.2 
May 23 
July 10 
2.6 
July 17 
1.7 
June 12 
July 24 
1.0 
June 19 
July 31 

