4 THE ALFALFA WEEVIL. 



second crop. Eggs have, however, been found as late as October 31 

 and larvae as late as the middle of November. 



The entire life of the insect, from the deposition of the egg to the 

 emergence of the adult, may be anj^where from 40 to TO days, while 

 the beetle itself ma}' live, including the winter, from 10 to 14 months. 

 In the first four years following its discovery the alfalfa weevil 

 has spread over a total area of fully 100 square miles of territory. 

 (See map, fig. 8.) So rapid has been its diffusion and so destruc- 

 tive its effects upon alfalfa that in the fall of 1909 the governor of 

 Utah appealed to the Secretarv of Agriculture for help in the inves- 

 tigation of the pest and in experimentation, with the hope of finding 

 some measures of relief. At the present time it is known to occur 

 from Salt Lake City southward as far as Provo and northward 

 probably to Ogden, as it has been found within a few miles of that 

 city. It occurs westward to Tooele and eastward, at any rate, as 

 far as Echo City. It will not be at all surprising 

 if by another spring it is found in southwestern 

 Wyoming, southern Idaho, Nevada, and perhaps 

 Colorado. The beetles have been repeatedly observed 

 in cars on railway trains passing in and out of Salt 

 Lake City. In one instance 27 were taken in the vesti- 

 bule of one sleeping car on a train in Salt Lake City 

 one day in July of last year, and have been found on 

 freight cars within sight of the Idaho line. There 

 Fig 7— The ai ^oes not appear to be any reason why it may not be 

 faifa weevil : carried in the same way over the San Pedro, Los 

 onTar^Td^ Augcles and Salt Lake Railroad and left in the al- 

 (0ri{?inai.) falfa fields of southern California, while by similar 



modes of distribution it may be carried by the Oregon Short 

 Line Kailroad into Idaho and by the Union Pacific Railroad east- 

 ward into the alfalfa fields of Wyoming and Colorado. (See 

 fig. 9.) It is within the range of probabilities that it may find an 

 eastern outlet over the Denver and Rio Grande Railroad into southern 

 Colorado and western Kansas. AMien we come to take into consid- 

 eration the fact that alfalfa escapes from cultivation, and in many 

 cases grows as a weed along these railways and roadsides, we can 

 well understand how easily these insects might be transported by the 

 railways and, losing their hold, drop off along the wa}^ and find 

 ample food in this alfalfa that has escaped from cultivation. 

 - Besides railways, there is another possible means of dispersion. 

 The beetles may, like those of some of the eastern species, be washed 

 into the tributaries of streams and, floating down, become established 

 in alfalfa fields along their borders. (See fig. 8.) 



