REPORT OF THE ENTOMOLOGIST AND BOTANIST 217 



SESSIONAL PAPER No. 16 



wheat plants, is an important discovery made by Prof. Webster, and suggests another 

 means of checking its ravages.' 



Remedies. — The remedies for tie Wheat Midge, as for all other insects which 

 attack crops, depend largely upon its habits and the way in which it passes the winter. 

 Those methods which have given the best results are as follows : — 



1. Deep ploughing directly the crop is carried, so as to bury the larvae so deep that 

 the flies cannot work their way out through the soil. 



2. The burning of all chaff, dust and rubbish known as ' screenings ' or ' tailings ' 

 from beneath the threshing machines, as these contain many of the larv£E which are 

 carried with the crop. If fed to chickens or domestic animals, this should be done in 

 a place where none of the puparia can escape destruction. 



3. Clean farming, including the cutting of all grasses along the edges of fields 

 and the ploughing down of all volunteer crops found in wheat fields before winter sets 

 in, so as to destroy an autumn brood where one exists. 



4. The cultivation of such varieties of wheat as experience has shown are least 

 affected by this insect. There is a great difference in kinds of wheat in this respect, 

 and from time to time so-called 'midge-proof varieties have been introduced, but it 

 is probable that there is no truly midge-proof variety of wheat as yet known. 



The Pea Weevil (Bruchus pisorum, Linn.). — The satisfactory state of affairs 

 referred to in my last years report as to the sudden and remarkable decrease in the 

 numbers of this pest has continued, and, even to a greater degree, during the summer of 

 1904. This sudden cessation of activity on the part of such a persistent enemy can- 

 not be accounted for by any one cause; but it must be claimed to be due, to some 

 extent at any ratx?, to the persistent work which has been done by entomologists in 

 stirring up farmers to greater care in treating their seed pease before sowing them, 

 and in harvesting and treating the crop as soon as possible after it is ripe. Many 

 farmers, for fear of loss from the depredations of the Pea Weevil, gave up growing 

 peas altogether during the last two seasons. In 1903 the numbers of the Pea Weevil 

 were perceptibly red'uced, but no natural parasites such as frequently bring down the 

 numbers of other insecte when they increase unduly, could be detected to account 

 for this. The winter of 1903-4 was more severe, both from its duration and the inten- 

 sity of the cold than has been experienced for many years. There is no doubt that 

 tlie cold weather destroyed majiy of the weevils which had emerged in the autumn 

 and were hibernating around barns and buildings. It is probable, too, that many of 

 those still remaining in the seeds through the winter were also killed by the cold. In 

 some rather extensive experiments carried on during two or three years to decide 

 whether there was any exact limit to the low temperature which could be borne with 

 impunity by the Pea Weevil, I found that beetles exposed inside tlie pease, both with 

 the skin of the pea intact or with the cell cap pushed off. were killed at between 18 

 to 20 degrees below zero, Fahr. On several occasions during last v.-inter the thermo- 

 meter dropped lower than 20 degrees below zero, Fahr., in those districts of Ontario 

 where the best seed pease are grown. Mr. Geo. E. Fisher, a practical farmer and care- 

 ful observer of insect life, writing from Burlington, Ont., on September 29, says : 

 * The pea crop here is now being threshed. It is a good crop and characterized by the 

 entire absence of bugs. This substantiates my contention tliat cold weatlier settles the 

 Pea Bug. I believe there will be a large acreage put in to peas next year.' 



Prof. C. C. James, in his November crop report for Ontario, says : * The round 

 or common field-pea has not been widely sown during the past three or four years 

 owing to the weevil or " bug." The yield and general quality of pease this season, how- 

 ever, will do much to restore confidence in the growing of this crop. The injury from 

 weevil was comparatively slight, and a larger area of peas may be looked for next year.* 



