192 EXPERIMENTAL FARMS 



8-9 EDWARD VII., A. 1909 



In my previous reports from observations I had made on material sent to me I 

 had suggested that an important remedy in controlling this insect would be the burn- 

 ing over of stubbles, but from Mr. Griddle's observations it would appear that tho 

 v/intcr location of this insect below the surface of the ground would protect it so 

 thoroughly as to render this practice almost useless. At ray request Mr. Griddle 

 made special observations on this point. He writes : — 



• Aweme, October 6, 1907. — At your suggestion I have just made experiments 

 with burning stubble to see what its effect would be upon Cephus occidentalis. As the 

 stubble was too thin to burn freely, and to make sure of having the experiment com- 

 plete, I spread an infested piece of ground with four inches of straw and then set fire 

 to it. This burnt decidedly longer than the thickest stubble would do and heated tho 

 ground on the top, so that it was luibearable to the hand. After it was cool I exam- 

 ined the inhabited straws, and though in some cases the top of the stubble cut off by 

 the larvas had been burnt, in no instance was a single larva found injured, but in 

 evei'y case they were found at the extremity of their burrows near the roots of the 

 plants, showing that the heat had merely had the effect of driving them downwards, 

 and as theii" tunnels in the straw usually extend from one to two inches below the 

 surface, they would practically be uninjured by this treatment.' 



The Wheat-stem Sawfly undoubtedly occurs in many places where its presence 

 is overlooked, but correspondents in Manitoba and the Northwest make frequent 

 reference to an injury in wheat fields which can only be referred to this insect. The 

 remedy which suggests itself and which has been practised to some extent is the 

 ploughing down of all stubbles either in autumn or before June 15, at which time the 

 mature insects may be expected to emerge. Mr. Griddle also suggests that all grasses 

 belonging to the genus Agropyrum growing around the edges of fields should be 

 mowed down during the last two weeks of July, so as to destroy any contained larva?. 



Wheat Joint Worm, Isosoma trUici, Fitch. — There is every year considerable loss 

 in the wheat crop of Prince Edward Island from the Wheat Joint Worm, and some 

 correspondents believe that the insect is spreading quickly throughout the province. 

 Father Burke, of Alberton, who has many opportunities of examining the crops, 

 believes it to be a serious matter, and regrets that more of the farmers do not con- 

 sider it specially with a view to adopting concerted measures for its control. The 

 adoption of a regular short rotation of crops and the mowing down of all grasses 

 along the borders of fields in June, as well as tlie keeping up of the fertility of the 

 soil, so as to produce a healthy vigorous growth, will not only discourage egg-laying 

 by the Joint Worm but will have many other beneficial effects on the land where 

 theae wise measures are practised. 



' Lower Montague, P.E.I., July 30. — I send you a few stalks of Laurel wheat. 

 This crop was sown on May 19, and appeared to be all right and looked splendid 

 until lately. On examining it I find a great many crooked straws similar to those 

 which I send. I have never seen this before. I have a field of White Fife wheat which 

 was sown on the same day as the Laurel, and this is very little affected. — Montague 

 Annear.' 



' Stanley Bridge, P.E.I., August 3. — The Joint Worm has totally destroyed all 

 the wheat in this vicinity and is spreading rapidly. As yet farmers have made no 

 effort to fight the pest. Will it take oats and barley if we give up growing wheat? — 

 A. J. McNeill.' 



'Bay View, P.E.I. , March, 190S. — In reply to your question, the Joint Worm of 

 wheat was first observed in our district in northwest Queen's county, at Long River, 

 about five years ago. The next seasoti it had spread five miles along the shore. The 

 remedies recommended were not applied, as the farmers on the Island seed down all 

 their wheat land with clover and grasses, and firing the stubble would destroy their 

 hay crop. In 1907 the pest had spread from Kensington along the shore to beyond 

 Rustico, a distance of over thirty miles, and some nine miles inland. All wheat 



