186 EXPERIMENTAL FARMS. 



CEEEALS. 



The grain crops of the Dominion have been little injured by insects during the past 

 year. Hessian-fly and Wheat-midge attacks were noticeably less in most of the districts 

 where inquiry was made. The American Frit-fly so destructive to spring wheat in the 

 Ottawa district in 1890, this season could not be found in wheat, and only in small 

 numbers in grasses. 



The Grain Aphis (SipJwnophora avence, Fab.) has, as usual, been complained of 

 to some extent from all provinces, but has not been the cause of serious loss. In the 

 Maritime Provinces, particularly in Nova Scotia, a peculiar affection of oats, by which 

 the tips of the leaves turned to a bright crimson hue, was very generally attributed to 

 the attacks of this insect. This however, I believe, was upon insufficient evidence. I 

 visited the Maritime Provinces early in August, and had an opportunity of examining 

 fields of oats, and wheat in Prince Edward Island. At that time, there was no trace of 

 the Grain Aphis in the fields, and the oat plants had outgrown the disease. Mr. J. 

 Vroom, of St. Stephen, writes : "July 21. What is the matter with the grain in this 

 section ? Nearly all the oats and barley fields are blighted, though it does not seem to be 

 the ordinary blight which the farmers ascribe to unfavourable weather. The newspapers 

 are saying that a ' bug ' is in the stalks, but the stalks seem to me all right." Writing later, 

 on Aug. 8, Mr. Vroom says : — " All the oat and barley fields about here are more or 

 less afiected, whether sown early or late. By newspaper reports from all the southern 

 counties of New Brunswick, I judge that the disease is widespread, if not general, in 

 this region. At Grand Manan, where seed time is a little later than on the mainland, 

 the fields were quite red in July, after those in this and the neighbouring parishes had 

 apparently recovered from the attack. When first noticed, usually when the plants 

 were about 6 or 8 inches in height, the tips of the leaves were turning red, much 

 redder than in the case of any blight that has been seen here in recent years. An 

 aphis was frequently seen at the base of the diseased leaf, and was by many supposed 

 to be the cause of the trouble. When healthy leaves succeeded and the fields were 

 again turning green, the aphides disappeared. The fields that were under best cultiva- 

 tion, were least affected, the strong and rapid growth of the plants enabling them to 

 quickly outgrow the rust." 



Although the cause of this disease is not yet explainable, from such inquiries as I 

 have been able to make, it seems to have been chiefly induced by unfavourable cold wet 

 weather in June, followed by a hot dry period. There were also present in the crimson 

 leaves, and probably the cause of that colour, myriads of a bacillus which was referred 

 to on page 179 of the Experimental Farms report for 1890, in an article by Mr. B. T. 

 Galloway, Chief of the Dmsion of Vegetable Pathology, of the United States, in the fol- 

 lowing words : — " The germ has been repeatedly obtained from diseased oats and grown 

 in various artificial culture media, such as nutritive gelatine, oat broth, hay infusion, 

 etc. Inoculations with this material have produced the disease in every case In shape, 

 the organism is sometimes nearly round, although, as a rule, it is several times longer 

 than broad. So very minute is it, that when magnified a thousand times, it is little 

 larger than the head of a pin." It would appear then that the plants were reduced in 

 vigour by unfavourable atmospheric conditions, and were then attacked by this disease, 

 due to a definite and recognizable organism ; but that, owing to the removal of the ag- 

 gravating cause by the improvement of the weather, the plants, particularly and more 

 quickly on well tilled farms, to a large extent outgrew the injury. As opposed to the 

 theory that this disease was due to the attacks of the grain aphis, the " crimson leaf " is 

 of such rare occurrence that, when it first appeared in 1890 as well as this season, it was 

 universally noted as something new; on the other hand, the grain aphis is invariably pre- 

 sent in some numbers every year and should, if it were a characteristic of their attack, 

 always produce the crimson leaves, which it does not. Moreover, as was first pointed 



