70 



Ball (E. D.). Estimating the number of Grasshoppers. — Jl. Econ. 

 Entom., Concord, viii, no. 6, December 1915, pp. 525-527. I 



In estimating the number of eggs laid by a swarm of Camnula > 

 pelhicida, the approximate area infested was determined after disking ; 

 the breeding ground so that the eggs appeared on the surface. The ; 

 heavily infested portion was found to contain, on an average, 175 eggs ; 

 per square inch. Young hoppers begin to migrate as soon as hatched, 

 always travelling towards the sun. In estimating the numbers in one 

 of the smaller migrating swarms, the central part of about 320 acres 

 was found to yield an average of 1 per square inch. Around this 

 centre was an average of from 10 to 15 per square foot. The swarms 

 were caught in balloon catchers, from 400 to 800 lb. being captured 

 daily with each trap. 



Webster (F. M.). Some Developments in Grasshopper Control.— Jl. 



Econ. Entom., Concord, viii, no. 6, December 1915, pp. 527-535, 

 1 fig. 



Periodical outbreaks of several species of grasshoppers in the 

 Merrimac and Connecticut River valleys in New England have 

 occurred for the past 40 years and at no time have these outbreaks 

 been satisfactorily controlled. The species involved are Melanoplus 

 atlantis, M. bivittatus, M. minor and Camnula pellucida. Investigations 

 were carried out during the spring and summer of 1915 to determine 

 the possibility of controlling the insects. It was found that the young 

 grasshoppers were more difficult to kUl with poison baits than the 

 adults. This difficulty was eliminated to some extent by doubling 

 the amount of fruit in the poison-bran mixture and adding that 

 ordinarily used in this bait to the Griddle mixture. It was discovered 

 later that dry bait was not attractive to the grasshoppers ; 

 consequently, baits were placed in the fields before sunrise. With 

 the poison-bran about 95 per cent., and with Griddle mixture 80 per 

 cent, of the adults were killed. Experiments in Florida, where 

 unsatisfactory results had been reported, showed that the bran-bait, 

 if properly prepared and applied, would be effective in destroying the 

 grasshoppers. In Galifornia, where M. differentialis, M. uniformis, 

 M. destructor and C. pellucida were involved, six lemons were used for 

 each 25 lb. of bran, with 2 qts. syrup and 3 gals, water. Lucerne meal 

 proved of equal value to bran. An attempt to control grasshoppers 

 by these poisons at Tempe, Arizona, was unsuccessful. When, later, 

 sorghum molasses was substituted for the ordinary molasses generally 

 used, the bait was found to be effective. The use of a hopperdozer 

 may be profitable when it is desirable to control the insects imme- 

 diately [see this Review, Ser. A, iii, p. 298]. In New Mexico, methods 

 of shallow cultivation have been carried out during autumn and winter 

 to destroy the eggs. Waste land in the North could be similarly 

 treated in autumn if thorough co-operative measures were undertaken 

 by farmers. It is probable that, were this carried out, serious attacks 

 of grasshoppers would not be experienced in any part of the United 

 States. 



