May a, xgai 
A Bacterial Budrot of Cannas 
145 
region (PI. 34, B). Infection often remains on one side of the stalk, 
which blackens and, if infected very young, fails to elongate like the 
healthy side and so cracks across at frequent intervals, the cracks becom¬ 
ing gummy with the exuded sap (PI. 36, C). Sometimes the rot extends 
along the stalk to its tip, blackening pedicels and well-formed buds. 
SUSCEPTIBLE VARIETIES 
During the summer of 1918 most of the varieties observed were healthy 
or showed only a trace of this disease. The badly affected sorts were 
Princeton, Gayety, City of Portland, and Charles Lutz. The disease was 
most virulent in the early summer, many plants recovering during August. 
In 1919 the outbreak was much more virulent than in the preceding 
year, but the susceptible varieties were different. This time the Yellow 
King Humbert, a sport from the Red King Humbert, and Carmine 
Beauty were most injured. Many of the varieties planted in 1918 were 
not set out in 1919, so no comparison could be made. It was learned 
from one of the gardeners that some varieties had been dropped in the 
past because of this budrot, among them Fire Bird and Mrs. Alfred 
Conard. Another gardener ascribed all the trouble to overwatering and 
crowding in the hothouse before setting-out time, conditions undoubtedly 
very favorable to the activities of the causal organism. 
DAMAGE DONE 
In 1919 the disease was observed earlier than in the previous year— 
that is, in the latter part of May soon after the plants were set out. At 
this time there were only scattering infections, a few large leaf spots, 
and several infected and dead shoots. Later (June 19) several beds 
showed from 10 per cent to 80 per cent of infected plants; of these many 
had two or three of the four shoots involved, and eight plants in one 
bed had bent blossom stalks. 
During July many plants outgrew the disease by sending out new, 
vigorous shoots; but in August, although to the casual observer no traces 
of disease were present, a great many unsightly leaves and some sickly 
young shoots might be found, and often a blossom stalk pushed up 
through a ragged brown sheath. 
In May, 1920, potted plants in the hothouse ready for setting out were 
examined, and the following varieties were found severely infected—that 
is, with a scattering of dead or diseased buds: Yellow King Humbert, 
Gayety, Golden Eagle, Dazzler, Favorite, and Wallace. 
Other varieties on the same bed and subject to the same conditions 
were entirely free from signs of the disease. These were Meteor, Olympic, 
Rosea Gigantea, Fenal, President, Princeton, and City of Portland. 
No connection could be traced between infected beds of one year and 
the serious attack of the following year. The beds most heavily infected 
in 1918 were in some cases almost disease-free in 1919, others were badly 
