REPORT OF THE ENTOMOLOGIST AND BOTANIST 179 



SESSIONAL PAPER No. 16 



The Sugar Beet "Webworm (Loxostege stictkalis. L.). — ^In my report for 1903 I 

 referred to an outbreak of the Sugar Beet Webworm in the West and treated it at some 

 length, so that in case of a future outbreak those who are now turning so much atten- 

 tion to the cultivation of the sugar beet in the Cardston district of Alberta, might be 

 prepared. During the past autumn I received an account of a local occurrence in that 

 district. Mr. J. B. Merrill, who is a most progressive farmer and fruit grower at 

 Magrath, Alta., writes on August 25 : — ' I Bend you by this mail specimens of worms 

 which are destroying our beet crops hero at an alarming rate. I take them to be the 

 Sugar Beet Webworm of your 1903 report What had we better do to control them? 

 We are spraying them with Paris green now, but the beets are stripped of their leaves. 

 Do you think tliat they will survive the attack and be of any use ? ' 



Mr. Merrill was written that he had applied the right remedy and that the plants 

 would certainly revive, but would be injured to the extent that the leaves had been des- 

 troyed, and that, although the roots would be reduced in size, they wotdd probably still 

 give a paying crop. That this proved to be the case is shown by a later letter from Mr. 

 Merrill : — 



' Magrath, Alta., Nov. 3. — I have to day delivered the last load of my beets on the 

 cars, so am now in a position to answer your questions. I had a very good stand of 

 beets on my 17 acres. Towards the end of August, after a three days' absence, I was 

 surprised to find the plants covered with worms. Part of the field had been irrigated. 

 Here the plants were not as badly affected as where they had no water. These latter 

 were swept clean, but they afterwards started a new growth of leaves, and from this 

 part of the field I harvested only four tons to the acre; but the watered beets yielded 

 13 tons to the acre. When ploughing up the beets, we found enormous numbers of the 

 worms about two inches under the surface of the soil. These we hope to destroy by 

 winter cultivation. I think that the moths must have come from an adjoining lucerne 

 patch.' 



The Spined Rustic (Barathra occidentata, Grt.). — During the month of July a 

 great many different kinds of plants in gardens were attacked at Ottawa by large, 

 smooth, cutworm-like caterpillars, which were at first greenish in colour, having the 

 body divided into two equal areas above and below the spiracles. The upper of these 

 areas, or the back of the caterpillar^ was darker by reason of some black patches, and 

 the under side of the body was of a yellowish hue. These rather inconspicuously marked 

 caterpillars were largely nocturnal in habit, coming out at night and feeding singly 

 on nearly all kinds of vegetation, but being particularly destructive to the seed pods 

 of larkspurs and to the foliage of the bleeding-heart (Dielytra spectahilis). Li the 

 vegetable garden, spinach and cabbages were most attacked. After the last moult, 

 about the middle of July, these caterpillars were much more conspicuously marked, 

 presenting a handsome Mamestra-like appearance, with three lines down the back and 

 with each segment ornamented with large velvety black patches; the head is honey- 

 coloured and mottled. When full grown these caterpillars are very voracious. They 

 are about two inches in length, cylindrical in shape like cutworms and attain a diameter 

 of nearly I of an inch. There is great variation in their colours, sonje specimens 

 appearing to be almost black while others have a dark olive green aspect; but all speci- 

 mens show a distinct band along the sides below the spiracles, which is clear yellow in 

 colour, marked centrally with red. These caterpillars were the progeny of a noctuid 

 moth which up to the present time has been a very rare species in all collections of 

 insects. It has been identified for me by Dr. J. B. Smith, as Barathra occidentata^ 

 Grt., an insect which is so rare that the only two specimens I had ever seen were two 

 reared by Mr. Guignard from larv^ which he had found upon larkspurs in his garden 

 in 1898. Mr. C. H. Young, of Ottawa, an energetic collector of moths, also took a 

 single specimen on June 6 of the same year, and another one the following year on 



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