186 ■ EXPERIMENTAL FARMS 



. 2-3 EDWARD VII., A 19D3 



The injury to clover crops in autumn by these voracious insects is often far more 

 serious than is generally appreciated. Grasshoppers are susceptible of being driven in 

 large numbers to the edge of a crop by drawing a rope across the top of it, the two ends 

 being held by two persons walking across the field. The poisoned mixture can then be 

 scattered on the bare ground at the edge of the crop to which they are driven. They 

 will eat this ravenously and vast numbers will be killed. 



MR. GRIDDLE'S REPORT. 



AwEME, Man., November 9, 1902. 



According to your request, I have prepared the following notes on the locust pest 

 for this year, at Aweme and the surrounding places. 



Locusts, on the whole, were decidedly more numerous than last year, especially in 

 places where they had not been poisoned the previous season ; but, owing to cold wet 

 weather in the latter part of April and the beginning of May, the first did not make 

 their appearance until May 7, and the bulk until the 26th, nor did they begin to do 

 damage until the end of the month. A succession of rains during June greatly retarded 

 their growth and saved a considerable amount of work in fighting them, as they do 

 very little eating during wet weather. 



On June 20, the first were noted with wings. By July 7, half could fly ; by the 

 11th most of them had wings, and they began migrating. The migratory season con- 

 tinued until the .30th, at which date the first eggs were being deposited. On August 12, 

 eggs were deposited for the second time. 4-fter this date eggs were being continually 

 laid until all the locusts died. They began to die off the latter part of August and had 

 practically all disappeared by September 20, a few remaining until the middle of October. 



In this season, as in 1900, locusts hatched out on the prairie in considerable numb- 

 ers wherever the ground was at all light or sandy. In fact, along the tract of country 

 lying between this place, Sewell, Carberry, and almost to Stockton, they were nearly as 

 plentiful as on the stubble fields ; but all those said to have hatched on the prairie of 

 the so-called heavy land, had in reality come from old gopher hills and other bare spots. 

 Unlike other years a large number hatched on heavy clay land, even after they had been 

 under water for some days. 



The chief damage done, was during the migratory period, by the locusts eating the 

 heads of grain, principally, however, owing to an erroneous notion among certain farmers 

 that it is useless to fight them after they can fly, and also because of a shortage of Paris 

 green at that time. With us very little damage was done (possibly a few bushels lost 

 during July). 



The locusts responsible for damage at Chater, Douglas, Blyth, Aweme, Treesbank, 

 Stockton, and almost to Wawanesa, consisted mostly of the Lesser Migratory Locust 

 (Melanoplus atlanis) a fairly large proportion of Packard's Locust (M. Packardii), a few 

 of the Two-lined Locust (M. hivittatus) and the Rocky Mountain Locust (M. spretus). 

 The latter were noted principally west of Treesbank. 



The only noticeable parasites or insects preying upon locusts that increased during 

 the summer, were sevei"al species of ground beetles (Amara) and blister beetles. These 

 latter were noticeable in fairly large numbers throughout most of the districts mentioned 

 above ; and here they have almost entirely exterminated the eggs in patches. The only 

 species seen in large numbers were a small black species, EpicatUa ^^'innsylvanica, and a 

 slightly grayer sort EjncatUa sericans. A small amount of damage was done by these 

 blister beetles to potatoes and beans ; but, as a rule, they prefer the wild peas or vetches 

 to any thing else. Tachina flies affecting locusts seem to have almost entirely disap- 

 peared during this season ; but the Locust Mites were about as numerous as usual. 



With regard to the strength of Paris green mixture, I had not much time to ex- 

 periment personally at home ; but experiments conducted by my brother, Evelyn Griddle, 

 show that undoubtedly 60 parts horse droppings can be used to one of Paris green (by 

 measure), and probably 75 parts. Whether it can be made yet weaker, as you surmise, 



