LIFE HISTORY OF TIMOTHY 31 
from meadows where the plants, are not making a very large or 
vigorous growth. There is no evidence, however, to indicate that 
the mass or volume of the average haplocorm is less on plants 
growing in cultivated row plats, or elsewhere where soil conditions 
cause a large and vigorous growth, than where the plants do not 
become so large (10, p. 3Jf). 
Haplocorms are almost invariably present on shoots which have 
elongated during the latter part of spring, but they are sometimes 
absent, or not well developed, on shoots grown under different con- 
ditions. On October 22, 1917, in a timothy meadow where the 
first crop of shoots had been harvested in the July preceding, 20 
shoots which had become elongated late in the season were examined. 
On each of 16, or 80 per cent, of these shoots there was a haplocorm, 
though its average size was somewhat less than is usual on shoots of 
the same size which elongate at the normal time in the spring. On 4, 
or 20 per cent, of these shoots there was no apparent enlargement in 
the diameters of the lowest elongated internodes. 
Some of the early botanical writers classed timothy plants with 
haplocorms as Phleum pratense nodosum. 8 Instead, however, of 
being a character which can be used to distinguish a distinct sub- 
species, the haplocorm is commonly present on the shoots of plants 
of P. pratense. 
RELATION OF THE HAPLOCORM TO VEGETATIVE REPRODUCTION 
There is a potential bud in the axil of the leaf at each node adja- 
cent to the haplocorm, but there is also a bud in the axils of other 
leaves. 
It has been assumed by different writers who have discussed the 
growth of timothy that the development of the haplocorm is essential 
to the vegetative reproduction of the plant (23, p. 9£; 38, p. lfl ; 10, p. 
303-306). However, buds in the leaf axils of the primary shoot of 
a timothy seedling very commonly develop into vigorous secondary 
shoots, with independent root systems, before a haplocorm has 
formed on the plant. Plate 2, A, is an illustration of a timothy 
shoot on which there were several innovations making a vigorous 
growth, although no haplocorm had developed on the shoot. It is 
clear, therefore, that the timothy plant is not entirely dependent on 
the haplocorm to perpetuate itself through vegetative reproduction. 
Whether the haplocorm may under other conditions have some 
effect on the growth of buds into shoots is not so clear. On plants 
in ordinary timothy meadows most of the buds remain dormant 
until about the time when the seeds mature, which is several weeks 
after the haplocorms have attained their full size. As has already 
been stated, the haplocorms continue to remain green and turgid 
for several weeks or months after the seeds have matured. It is dur- 
ing this period when the haplocorms are in their prime that large 
numbers of shoots on plants which grow in timothy meadows de- 
velop from buds. In a series of chemical anatyses made at the Mis- 
souri Agricultural Experiment Station at six different intervals from 
the time when shoots of timothy plants were about 1 foot high until 
the seeds had matured, the haplocorms were found to contain less 
8 Fraser, S. timothy. Cornell University thesis, p. 75-80. 190o. Unpublished. 
