REPOBT OF THE SICIETY 



77 



all in wheat", of "Earcockle" etc., are cases in point, and in anticipation of 

 such possibilities we wish to be prepared, in order to be in a position to discuss 

 with some knowledge the risks involved. 



A stuty of the diseases convej'^ed by seeds, the mechanism by which seeds 

 become carriers, reliable information on the questions of rational and effective 

 control of seed borne diseases, together with precise information on their 

 recognition in field or in the package, you will agree is urgently called for. 



OAT SMUT CONTROL EXPERIMENTS IN 1923 

 Dr B. T. Dickson, Macdonald College, Que. 



Smut control experiments, conducted in co-operation with the Crop Protec- 

 tion Institute, were again carried out at Macdonald College using Hull-less 

 709 M. C. oats and Ustilago levis (K. and S.) Mag. The plots were 5 x 20 

 links in size, were replicated four times, and were separated by filler plots of the 

 same size. 



Grain was- treated on May 25th and seeded on May 26th. On the day of 

 seeding the moisture content of the soil was 9.5% and it continued comparati- 

 vely dry until June 9th when a wet spell set in giving a period of four days with 

 a soil moisture content of 25%. From that time on the season was normal. 



The grain was heavily inoculated giving 70% of smut in untreated plots so 

 that a reduction to less than 2% of smut by head count was quite satisfactory. 



Several interesting observations were made which, while wellknown, are 

 still worth recording. Concerning stooling, for example, the inoculated by 

 uncontrolled plants stooled much more than treated as is shown in the following 

 table. 



STOOLING.— ACTUAL COUNT OF NUMBER OF CULMS. 



