4. Farmers’ Bulletin 1262. 
range annually from 40 to 160 miles, although in several instances the 
winter conditions have caused a decrease in the infested area. During 
the first 10 years after its advent into this country the annual rate of 
spread of the weevil was 5,640 square miles. From 1901 to 1911 the 
annual increase in the infested territory averaged 26,880 square 
miles. In 1916 it reached 71,800 square miles. Of course, the figures 
given do not refer to the area in cotton. In many parts of the in- 
fested territory the area devoted to cotton is much less than 10 per 
cent of the total area. 
The territory in the United States in which the boll weevil 
occurred at the end of the year 1921 is shown in figure 1. At the 
end of that year over 600,000 square miles of territory had been 
infested by the boll weevil, leaving only about 105,000 square miles 
of cotton-producing territory uninfested. Practically 85 per cent 
of the cotton belt is now infested by the weevil, and the area now 
infested produces 94.6 per cent of the cotton crop of the cotton belt 
of the United States. 
A form of the boll weevil is found in the mountains of Arizona 
feeding upon a wild plant related to cotton. This variety has been 
under observation for a number of years, and finally was noted in 
1920 attacking cultivated cotton north of Tucson, Ariz., between that 
city and the Santa Catalina Mountains. The State of Arizona is 
attempting to eradicate this infestation by a noncotton zone in the 
infested district. 
The boll weevil is known throughout the larger portion of Mexico 
and southward to Guatemala and Costa Rica. It is known to occur 
also in the eastern half of Cuba. 
DAMAGE. 
The losses caused by the boll weevil are both direct and indirect, 
and extend throughout practically the entire financial and economic 
structure of the ‘cotton belt. It is impossible to estimate the losses 
due to depreciated land values, closing down of cotton gins and oil 
mills, and other indirect results of the weevil invasion. All esti- 
mates have been made entirely on the basis of the direct loss in 
nonproduction of cotton lint and seed. The Bureau of Crop Esti- 
mates of the United States Department of Agriculture in the fall of 
1920 estimated an average annual loss for the last four years of about 
$300,000,000. Other estimates have differed somewhat, but certainly 
the annual direct loss is now well in excess of $200,000,000. 
The damage in individual fields is influenced by many factors 
and varies widely, ranging from slight injury to complete destruction 
of the cotton crop. A fair idea of the possibilities of loss is afforded 
by the gains which have been secured in recent poisoning experi- 
