28 PRELIMINARY MPORf ON ALFALFA WEEVIL. 
2 5 til of May, and observations made at the time indicate that while 
many of the full-grown larvae were collected, most of the smaller 
ones were left among the buds. On May 29 the field received a 
second irrigation. The larvae at this time were very abundant; the 
gathering machine, too, had retarded the growth of the plants by 
breaking off the growing tips and some of the plants themselves had 
been broken down by the collecting machine. As a result the alfalfa 
had apparently made little or no growth since about the 22d, and its 
value as forage was at that time rapidly decreasing. 
A wire-brush machine (PL YI, fig. 1) was constructed by Mr. L. 
Hemenway by bolting about 30 pieces of No. 8 steel wire 7 inches 
long between iron clamps on each spring tooth of an old spring-tooth 
cultivator. The ground was gone over with one of these on June 1, 
as soon as the hay had been removed. The jumping action of the 
spring, together with the wire brushes, proved very effective in crush- 
ing larvae and pupa3 among the stubble. The field was then gone 
over with a plank leveler, shown in Plate VIII, figure 2, with square 
iron edges bolted to a plank. June 7, the field received another 
brushing with the wire-brush machine, which crushed cocoons and 
larvae. By June 13 the second crop in this field had started nicely 
with very few weevils present. In another field near by no attempt 
had been made to treat it or to remove the weevil, and this field was 
taken as a check on the one under treatment. An examination at 
this time showed that when the former field was in good condition, 
with few larvae, the field that had received no treatment was bare 
and brown from their attack. 
On June 22 the second crop of alfalfa on the treated field was about 
8 inches high, while the unworked field was still bare and its condi- 
tion, on June 27, is shown in Plate VI, figure 3. By the 27th the 
alfalfa in the treated field was about 1 foot in height (see PI. VI, 
fig. 2), the stand extra good, and the treatment had seemed to free 
the field from weeds and other foreign growth. By July 7 the plants 
were about 2 feet in height, while, of course, both the adults and 
larvae could be found to some extent in this field. July 27 the second 
crop harvested 2 tons per acre, selling at $9 per ton in the field. The 
field at time of harvest of second crop is illustrated in Plate VII, 
figure 1 . The unworked field, however, was making an inferior second 
crop, coming just a little in advance of the third crop in the treated 
field. 
From the treated field there was also a fourth crop of hay secured. 
The field was photographed on October 9, 1911, and the yield of hay 
is illustrated in Plate VII, figure 2. The condition of the check field 
a few days later, October 12, is shown in Plate VII, figure 3; here the 
second and third crops were both not only badly damaged, but so 
delayed in growth of alfalfa that, as shown by the illustration, no 
fourth crop was secured at all. 
