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FIELD EXPERIMENTS IN DESTROYING WEEVIL. 2T 
indicate, however, that the brush arag does not destroy as many of 
the larvae as one would suppose, and for this reason some harsher 
measures have been put into application during the season of 1911. 
Street-Sweeper Experiments. 
The ordinary street sweeper, such as is used in our cities, appears 
to be a most thorough measure of destroying the pupse. This much 
was determined by the Utah Experiment Station. A street sweeper 
(PL V, fig. 1) was used in a field on June 22, 1911. While examina- 
ation showed that the result of this treatment, at this time, was to 
kill most of the larvse and pupae, it did not kill a great percentage of 
the adult weevils, which had already developed in large numbers. 
It would have been much better had this work been carried out about 
two weeks earlier; not only the condition of this field but of others 
in the neighborhood treated between June 14 and July 1 indicated 
that considerable good had resulted from this treatment even at this 
late season. On another farm, owned by Mr. Breeze, southwest of 
Salt Lake City, a field was swept with the street sweeper about the 
14th of June with a view of interfering with the work of the weevil. 
By July 7 the alfalfa in the Breeze field was about 20 inches high 
with very few weevils present. (See PL V, fig. 2.) Twenty days 
later the alfalfa was 30 inches high and in full bloom, being ready for 
the taking of a second crop. Just across the road from this farm 
was a field where no treatment whatever had been applied against the 
weevil. In this field the alfalfa plants were only about a foot in 
height and very much delayed (PL V, fig. 3). This seems to indicate 
that as a protection for the second crop the measure has considerable 
value. The drawback here is in the expense of a street sweeper, 
although of course where the members of a community club together, 
or in case of very large alfalfa fields of several hundred acres, the 
first cost of this sweeping machine would not constitute such an 
important item. 
Wire-Brush Experiment. 
A 13-acre field of alfalfa 7 years old had been disked in the spring 
of 1910. The first crop of alfalfa was reported to have been reduced 
to one-half by attack of the weevil. A weevil-collecting machine 
had also been used on this first crop, but there were still enough of 
the weevils left in the field to greatly retard the second crop. It was 
disked and dragged again and a fairly good yield of the second crop 
was secured. This was also true of the third crop in this same field. 
On May 15, 1911, there was a good stand of alfalfa in this same 
field. One irrigation had at this date been applied. The plants 
were a little over a foot in height, and while at the time, May 15, they 
were in fairly good condition they were heavily infested with weevil 
larvae. The gathering machine was used twice between the 17th and 
