64 BULLETIN 1476, U. S. DEPARTMENT OF AGRICULTURE 
before examination occurred, so the percentages given represent 
minimum figures. When the injury occurred in the lower part of 
the stems and after the plants had become fully developed, the 
blooms were suitable for sale. The estimated loss amounted to 6 
per cent of the value of the crop during 1922 in houses showing 
maximum infestation. 
Gladioli 
The flower stalks of gladiolus plants were infested by the corn 
borer (fig. 19), and egg clusters have occurred on the leaves, in 
a few fields each year since 1918. Usually this infestation has been 
very sparse, but in 1919 a maximum of 6 per cent of the flower 
stalks were injured by the borer in two fields grown in close 
proximity to other infested crops. In 1921 and 1922 a scattering 
infestation was found in the majority of fields examined, but less 
than 1 per cent of the plants were involved, and the economic loss 
in any instance was trivial. No infestation or injury to the bulbs 
has been observed to date. 
Zinnias 
The stalks and flowers of zinnias commonly are infested by the 
corn borer in home gardens and small commercial establishments. 
During the late summer of 1922 there was a decided increase in 
the injury to zinnias as compared with former years, but most of 
this injury occurred after the better blooms had been picked, and 
was, therefore, of little economic importance. In many of the home 
gardens of the Boston area practically 100 per cent of the plants 
were infested, and in one instance 90 per cent of the blooms con- 
tained the borer. 
Oats 
The stems (culms) of oats have occasionally been found infested 
(fig. 18) when growing as volunteer plants and in experimental 
areas. This crop rarely is grown commercially within the area 
where the European corn borer is numerous at present. In 1921 
a small experimental plat of oats was grown in close proximity to 
infested corn and other susceptible plants. Only a fraction of 1 
per cent of the stems were infested at the time of harvest. After 
being cured in the usual manner, part of the straw was baled and the 
remainder left loose. A detailed examination of about 58,000 
straws from both lots revealed that living borers were present in 
the baled straw at a rate of 8 borers per 100 pounds, and in the loose 
straw at a rate of 11 borers per 100 pounds. 
Other Field Crops 
In order to obtain information relative to the susceptibility and 
extent of injury by P. nuhilalis to various field crops which normally 
are not grown to any extent in the Boston area, small plats of these 
crops were grown in the experimental fields at Medford. Saugus, 
Cambridge, Belmont, and TVoburn, Mass., during the period from 
1919 to 1922. Some of these crops, such as cotton and the grain 
sorghums, are seldom, if ever, grown in this section of the country. 
The more important information obtained from these plats is sum- 
marized in Table 19. 
