April, ’18] 
MORRILL: GRASSHOPPER BAITS 
185 
In demonstration work one of the most effective applications of 
% 
bran mash which the writer has ever observed was put out in a cotton 
field on July 3, 1917, between seven and eight o’clock in the morning. 
We have usually recommended that the bait be put out as soon after 
daybreak as possible and in general our observations in Arizona show 
better results from early morning applications than from applications 
made late in the afternoon. The data summarized in the foregoing 
table suggests thafi bait for the differential grasshopper may be spread 
with good results during the warmer part of the day up to 3 or 3.30 
p. m. Working with another species of grasshopper (Eucoptolophus 
subgracilis Caudell) near Yuma, Arizona, on October 20, 1917, and a 
few days following, Mr. J. L. E. Lauderdale reports good results in 
killing the hoppers with bran mash applied between 3 and 3.30 p. m. 
Amount of Alfalfa Consumed by Grasshoppers 
There are times when farmers hesitate to spend forty or fifty cents 
an acre for materials with which to poison grasshoppers. In our work 
in Arizona a need was felt for a definite basis for estimating the daily 
damage done by these pests. Consequently two tests were conducted 
(July 18-20, 1917) with adult specimens of the differential grasshopper 
in order to determine the capacity of this species for destroying alfalfa. 
In the first test 50 adult specimens were used. A lot of freshly cut 
alfalfa weighing eight ounces, with stems in a bottle of water, was 
placed in a wire screen cage containing the grasshoppers and a check 
lot of ajfalfa was placed in a nearby cage. Twenty-four hours later 
only 37 of the 50 insects could be found in the cage. The two lots of 
alfalfa were weighed and the amount of green alfalfa destroyed by the 
hoppers was computed. It was found that the check had decreased 
18.2 per cent in weight while the lot on which the insects fed decreased 
38.8 per cent. The net difference in weight was 44.87 grams. As¬ 
suming that the 13 missing specimens averaged twelve hours in the cage 
before escaping, the average amount of green alfalfa destroyed by the 
hoppers was approximately one gram. Of this about 6f milligrams 
consisted in leaves and tender stems which were severed and had 
dropped to the ground. At this rate an average of 7.56 adult hoppers 
per square yard would be capable of consuming green alfalfa which 
would be equivalent to 1/100 of a ton of alfalfa hay per acre or one ton 
for 100 acres. 
In the second test 25 adult specimens were used and as all were ac¬ 
counted for at the end of twenty-four hours the data obtained is more 
satisfactory than in the first test. The amount of green alfalfa de¬ 
stroyed averaged 12/5 grams for each insect. At this rate an average 
of 6.3 adult hoppers per square yard would destroy green alfalfa 
