REPORT OF THE ENTOMOLOGIST AXD BOTAXIST 



217 



SESSIONAL PAPER No. 16 



bers to reduce materially some serious outbreaks of insects without being noticed 

 even by careful observers. 



Remedies. — The habits of the Hessian Fly and the best remedies are widely 

 known by those concerned, and with co-operation a great deal can be done to reduce 

 the injuries by this most destructive insect enemy of our staple crop. The best 

 remedies are : — (1) Late sowing, preceded by trap crops sown in August and ploughed 

 down by the middle of September ; (2) Thorough preparation of the land — Prof. 

 Webster lays great stress on this ; (3) The burning over or ploughing down of stubble 

 on fields which have been infested ; (4) The burning of screenings and refuse after 

 threshing ; (5) The use in spring of quick-acting fertilizers upon a slightly injured 

 crop. 



CUTWOKMS IN GRAIN. 



Injury to growing grain by cutworms has been complained of more 

 frequently than usual. By far the widest-spread and most disastrous outbreak 

 was in central Manitoba toward the end of June. Reports of injury were received 

 from Minnedosa, Baldur, Springfield, Kildonan, Niverville, Miami, Roland and Rose- 

 bank. The loss in oat fields in the Carman district was great. The Hon. R. P. Roblin, 

 the Minister of Agriculture for Manitoba, who lives in this district, told me when 

 examining these fields with me that he had never seen such an outbreak for twenty 

 years. Many fields of oats which had been eaten bare, were sown' again to oats or to 

 barley. One very remarkable feature of this occurrence was that the cutworms, al- 

 though showing a great preference for oats, would also eat wheat and to a much smaller 

 extent barley, but if they began on any one of these crops, they seldom spread into an- 

 other. A great many oat fields were seen which had been eaten almost, or quite bare, 

 right up to the edge of a crop of wheat with nothing whatever intervening, and the 

 wheat plants were apparently quite untouched. Occasionally, but very rarely, the oppo- 

 site to this was observed. At the time of my visit, July 1, most of the cutworms had 

 already attained full growth and it was difficult to find them. Such as were found 

 proved to be the Red-backed Cutworm (Carneades ochrogaster, Gn.). This species 

 seems to be very peculiar as to its food habits. It is one of the commonest and most 

 destructive cutworms in the Ottawa valley where it attacks particularly spinach, cab- 

 bages, tomatoes, beet-root and onions. In grain fields and on unworked land it con- 

 fines its attacks almost entirely to the Lamb's-quarters (Chenopodium album, L.), a 

 wild spinach, and I have many times noticed grain fields, of both oats and wheat, in 

 which every plant of Lamb's-quarters had been eaten down, but not a single stem of the 

 grain was touched. I was therefore very much surprised to note its unusual habit in 

 Manitoba of attacking growing oats and wheat. Where very abundant, however, it 

 did not always confine itself to a single food plant, for in a garden which I visited at 

 Morden, Man., all kinds of vegetables had been destroyed. 



The injuries in grain fields in the Ottawa district in Ontario were by a different 

 gpecies of cutworm, namely, the Glassy Cutworm (Hadena devastatrix, Brace). These 

 greenish white caterpillars with reddish heads, unlike many other cutworms, seldom 



come above the surface of tho ground, even at night, 

 but lie hid among the roots of various kinds of grasses, 

 cutting off the shoots at the base. These were reported 

 by Mr. Meredith Caldwell as having done much harm 

 in wheat and oat fields at Luskville, near Eardley, Que. 

 They were worst on clay and marl ridges, but were also 

 very destructive on level clay lands. Prof. Lochhead 

 also tells me that about Gravenhurst, Muskoka, many 

 fields of oats 15 to 20 acres in extent were badly injured 

 by the same cutworm between May 10 and 25. This 

 species as a rule is only troublesome in grain fields sown on grass lands which have 



Fig. 3. — The Glassy Cutworm. 



