THE BROAD-BEAN WEEVIL. 7 



The damage according to the different horse-bean regions is shown 

 in the following table : 



Table III. — Summary of the IHIH, I'Jll, and 1UJH crops of broad beans shotmng 

 tlic pcrvent(it/c of irccvil in festal ion hi/ localities. 



% 



1910 



in[e.st;i- 



lion. 



1917 



info.sta- 



tion. 



1918 



infcsta- 



lion. 



Sacramento: 



Per cent. 

 41 

 

 9.09 



50 

 

 14.5 



55 

 

 13.6 



70 

 

 24 



Per cent. 

 63 

 



12.7 



C3 

 

 14.5 



56.6 



.5 



10.9 



46 



1 



16 



Per cent. 

 84.3 





1 



Average 



22.4 



Ocean o-Morro: 



17.2 











2.92 



Halfmoon: 



56 











16.8 



Gilroy: 



Maximum. . . 









Average . . 









Table II shows that of the entire crop of broad beans for the three 

 years 1916, 1917, and 1918, 31.21, 18.01, and 43.08 per cent, respec- 

 tivel3^ were above the 15 per cent limit of weevil infestation allowed 

 by the Bureau of Chemistry, and therefore could not be shipped un- 

 less hand picked. Table III shows that even 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 of the 

 Sacramento and Halfmoon districts for the 1918 crop. This table 

 also shows some interesting data on the increase in infestation. 

 Sacramento is a comparatively new district for raising broad beans, 

 and at first the weevil infestation was low, but as planting continued 

 from year to year, and the acreage increased, the percentage of in- 

 festation greatly increased, going from a maximum of 41 per cent 

 in 1916 to 63 per cent in 1917 and 84.3 per cent in 1918, while the 

 average p'ercentage of infestation for the same years increased from 

 9.19 to 12.7, and then to 22.4 per cent. Climatic conditions at Sacra- 

 mento are adverse to late planting, and early planting as practiced 

 there is favorable to heavy weevil infestation. Unless control meas- 

 ures are practiced, and only uninfestecl or treated seed is planted, this 

 district soon will be in the same position in regard to the production 

 of horse beans that Alameda County has been in for some years. The 

 low percentage of infestation in the Oceano-Morro district for the 

 year 1918 will be explained later. 



Estimates from bean brokers on the reduction in value of broad 

 beans from the infestation of the wee^dl vary from 25 per cent to 

 total unsalability, depending on the degree of infestation. 



