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•central, and eastern parts of the State, where entire fields, many acres 

 in extent, were rendered absolutely bare of vegetation. This condition 

 was brought about by the grain being checked by frost early in the 

 spring and when it was about four or five inches high, an invasion of 

 the young nymphs of Camnula pellucida, Scudder, and Melanoplus 

 atlantis, Kiley, utterly destroyed the crop, not a blade of grain being 

 left. In hay lands, the grasshoppers developed on high ground, and 

 as soon as the irrigation water was removed, they moved on to the 

 more tender grass, in many cases causing a loss from 25 to 50 per cent, 

 of the hay crop. Large areas of pasture land have also been badly 

 damaged in the same way. Young orchards were badly injured and 

 in a number of cases the trees were entirely defoliated. In the lucerne- 

 crowing sections of Oregon, the crop was materially reduced. Details 

 are given of an invasion of grasshoppers, and on 1st July 1914, a 

 consultation was held for the purpose of determining upon a plan for 

 destroying the migrating host, which was then travelling across the 

 fields and making great inroads upon the crops. Most of the grass- 

 hoppers present were still in the nymphal stage, though a number 

 were winged. The unwinged individuals were' held in check on certain 

 fields by the large drainage ditches, and millions had been driven into 

 these and destroyed. A series of experiments were carried out to 

 determine the best combination of poison bran to use, and the best 

 time and method of application. Three combinations were made 

 up and in each cSse enough water was added to make a crumbly mash. 

 The use of oranges and lemons [see this Review, Ser. A, ii, pp. 249 and 

 542] was considered as too expensive, and although each combination 

 was about as attractive as the others, the following one (containing 

 lemon extract instead of the fruit) attracted a greater number of 

 grasshoppers in a shorter time: Bran 501b.; Paris green, lib.; 

 salt, 1 lb. ; and lemon extract, 1 oz. According to the number of 

 grasshoppers found dead in the immediate vicinity of the bait, one 

 pound of Paris green seemed to be as efficient as two. The best results 

 w^ere obtained by spreading the bait early in the morning before the 

 dew was off the grass. Following these experiments, a meeting of 

 growers was held, and based upon the recommended use of 10 lb. of 

 bait per acre, a certain amount was assessed to each grower, depending 

 upon his acreage. The grasshoppers began to die within a day or 

 two of the application, and within a week were only present in limited 

 numbers, millions of them being dead in the treated fields. The two 

 species causing the greater part of the damage were C. pellucida and 

 M. atlantis. Anabrus simplex, Hold., Steiroxys borealis, Scudder, and 

 Pseudotrimerotropis {Trimerotropis) vinculata, Scudder, were also 

 plentiful, while in western Oregon, Melanoplus femur-rubrum, Harr., 

 is the most serious grasshopper pest. 



Disking or ploughing in the autumn or early spring to destroy the 

 ■eggs, is the most satisfactory method of control other than the poison 

 bran-mash. The hopper-dozer has given satisfaction only in isolated 

 cases, and those growers who have tried the poison bait broadcast 

 are strongly favourable to that method and will follow it next season 

 (1915). Two parasites attack grasshoppers in Oregon, viz., a red 

 mite, probably Trombidinm locustarum, Riley, and a fly, Sarcophaga 

 kelhfi, Aldrich [see this Review, Ser. A, iii, p. 81.] The former may 

 be found on the grasshoppers all through the summer, and in one case 

 over 1(X) mites were counted in various stages on a single individual. 



