90 Farmers’ Bulletin 1275. 
The broad-bean weevil (Fig. 20), sometimes called the European 
bean weevil, is common and destructive in Europe and North Africa. 
While it feeds upon various sorts of beans and peas, it appears to 
prefer the broad or Windsor beans (see Fig. 21). Although it has 
been found from Canada to Texas in Windsor beans imported into 
various parts of this country, the first discovery of its definite estab- 
lishment in the United States was made in 1909 at San Luis Obispo, 
Calif., where it was injuring the broad or Windsor bean (Vicia faba) 
grown for stock feed. 
Since then, and up to 1920, it has spread to include the coastal 
counties of California, from Sonoma to San Luis Obispo, besides San 
Benito, Santa Clara, Alameda, San Joaquin, Sacramento, Yolo, 
and Napa. Practically every bean entering the warehouses of New 
York is often more or less damaged by this pest. A single grub 
in its development consumes approximately 3 per cent of the bean. 
Sometimes as many as six weevils develop in a single bean. Beside 
the actual amount of seed consumed there must be considered the 
frass of the insect left behind in the seed and this still further re- 
duces the value of the crop. It has been stated that of the entire 
broad-bean crop of California for the years 1916, 1917, and 1918, 
31.21, 18.01, and 43.08 per cent, respectively, were above the 15 per 
cent limit of weevil infestation allowed by the Federal pure food 
law, and therefore could not be shipped unless hand picked. In 
1916 the average percentage of infestation for the entire 1916 crop 
in the Halfmoon and Gilroy regions was above the 15 per cent limit, 
while the same is true for the Sacramento and Halfmoon districts 
for the 1918 crop. After a campaign of seed fumigation in San 
Mateo County during 1918, 1919, and 1920, it was reported that the 
percentage of the broad bean crop infested 15.1 per cent or more 
was reduced from 48 per cent in 1918, to 21 per cent in 1919, and to 
17.8 in 1920. Since beans uninfested, or infested less than 15 per 
cent, were worth during these years from 5 to 6 cents per pound, 
and others only 2+ to 3 cents, it is easy to appreciate the dollars 
and cents value of concerted action among growers in applying 
cheap, but effective, remedial measures. 
The following biologic facts are taken from a report of experi- 
ments conducted at Alhambra, Calif The egg stage lasts from 
9 to 18 days, the larva stage from 10 to 15 weeks, the pupa stage 
from 7 to 16 days, and the beetle lives from 1 to 8 months. The 
eggs are laid on the green bean pods in the field from the middle 
of March to the middle of May; the larvee reach maturity from 
August to October, while the adults can be found from August to 
the following June. The broad-bean weevil has but one genera- 
18 Campbell, R. E. The Broad-Bean Weevil. U. 8S. Dept. Agr. Bul, 807. 1920. 
