12 BULLETIN 57, HAWAII EXPERIMENT STATION 
attached to it, which are termed the first generation. The rootstocks 
directly attached to the first generation are the second generation, 
and so on. Thus, a hill can be dug after 12 months and the progressive 
stages of growth traced from the original seed rootstock. 
CLASSIFICATION 
In classifying the rootstocks in a hill they are grouped as (1) dor- 
mant, (2) mature, and (3) immature. The immature group is further 
divided into (a) rootstocks with little or no meristematic growth; 
and (b) rootstocks with meristematic growth. Since the transition 
from immaturity tofmaturity and thence to dormancy is rather 
gradual, it is deemed necessary to define the limits of each group in 
some detail. 
The dormant group comprises plants on which the leaves have 
died and the stems have or have not yet shriveled. 
In the mature group the oldest members still bear a green leaf at 
the apex, but the lower leaves are dead. The lower leaves are begin- 
ning to shrivel at the edges on the younger members and growth 
of new leaves at the apex has practically ceased. A stalk in the 
bud or bloom stage is placed in the mature group even though the 
basal leaves are still green. 
The stalks of the oldest members of the immature 3a group have 
attained nearly full height with the basal leaves still green, whereas 
one leaf is beginning to unfold on the youngest members. 
The oldest members of the immature 3b group have not yet begun 
to develop stalks, whereas the youngest members have just emerged 
from the bud stage. All members of this group are thus young 
" spikes." They are fresh in appearance and the basal scales show 
little sign of shrivelling at the edges. They are deep purple whereas 
the epidermis of the rootstock is pink at the apex. 
Some spike rootstocks, the stalks of which fail to develop, remain 
in every hill. Usually either the parent or the offspring has a stalk 
and the "spike" is placed in the next younger group than the parent 
or the next older group than the offspring. A comparatively small 
"spike" which is attached to a mature rootstock and bears no off- 
spring is classed as a part of the parent rootstock. 
The division between the youngest members of the immature 
group (3b stage), and developing buds is necessarily inexact and 
relative. This division can not be based on size, which varies with 
the field and the stage of maturity. Usually, however, the uncer- 
tainty is small when the general rule is followed to classify as buds 
all those which have not become "sizeable" and have no definite 
"rounding in" at the attachment with the parent. 
APPLICATION OF METHODS 
Application of the above-outlined methods to edible canna of 
various ages and grown under widely different climatic conditions, 
has demonstrated that they have certain definite limitations. Gene- 
alogization, while comparatively simple in the first 8 to 10 months 
of growth, is rendered practically impossible with a hill 18 to 20 
months old, by the death of the original stalks and the growth of 
one line of rootstocks over another, and its use is consequently 
restricted to determining the early tendencies of growth of individual 
hills. 
