REPORT OF THE DIRECTOR 27 



SESSIONAL PAPER No. 16 



Prof. Jolm Adams, M.A., formerly connected with the Royal College of Science, 

 Dublin, Ireland, received the apiDointment as Assistant Dominion Botanist. 



Mr. r. Lisle Drayton, B.S.A., a graduate in hiology from the Macdonald College, 

 was appointed Assistant in Plant Pathology and Bacteriology. 



The work of this Division has steadily increased. The special attention which is 

 being paid to the control of plant diseases and to a general plant pathological survey 

 of the Dominion, emphasizes the necessity for considerable experimental work and 

 increased activity in this direction. It appears that, no matter how recently land may 

 have become utilized for agricultural purposes, the economic crops soon fall a victim 

 to destructive diseases, which may cause either a direct reduction in yield, or con- 

 siderable trouble through loss of trade. 



DESTRUCTIVE INSECT AND PEST AC*r. 



A striking example of the latter is afforded by the disease " powdery scab " 

 affecting potatoes. This disease, known for nearly a century in Europe, has been 

 recorded for the first time on the continent of America. Its presence here was regarded 

 by the Dominion Botanist as of scientific interest, and was recorded merely from tliis 

 point of view. It resembles closely the common potato scab, and is in the opinion of 

 nearly all plant pathologists who have had experience with it, a minor disease, which 

 deserves no more attention than the well-known common scab, which is distributed all 

 ovdr the world. Even under Canadian conditions, the disease, which has been most 

 carefully watched since it first came under^ observation, has shown itself certainly 

 more harmless in effect than " late blight " or " black leg " or other well-known potato 

 diseases. 



There was little reason for this disease to become practically the most notorious 

 plant disease known in Canada. As is well known, the United States authorities con- 

 sidered the disease in quite a different light. They regarded it, because of their having 

 had no actual experience with it, as very suspicious and of sufficient importance to 

 warrant their placing an embargo on all Canadian potatoes. This action made the 

 disease at once — at any rate to the growers and shippers of the Dominion — ^the most 

 important potato disease. Under ordinary circumstances, the. disease would have been 

 dealt with in the manner its minor character deserved, but the embargo affected very 

 seriously the market for the crop of Eastern Canada. For this reason, negotiations 

 were begun by the expert of our department, who was instructed to discuss the condi- 

 tions under which the embargo would he raised. In June, the Dominion Botanist 

 interviewed the United States Federal Horticultural Board, who were prepared to 

 permit the importation of potatoes, providing certain conditions would be fulfilled. 

 These conditions required certification of all potatoes, after inspection of farms and 

 of the potatoes prior to shipment from the defined so-called " infected area " within 

 the Dominion. The conditions were regarded as very complicated, and their enforce- 

 ment would require a large staff of inspectors and a considerable expenditure. The 

 departm.ent, however, desirous of accommodating the agricultural population of 

 Eastern Canada, who are prominently engaged in raising potatoes, caused those 

 regulations to be explained to the shippers who were most actively interested, i.e., 

 those of New Brunswick. The same conditions were laid by the United States 

 authorities upon the state of Maine (and later New York), on finding these states 

 infected by the same disease. The Canadian shippers unanimously agreed to accept 

 the conditions, and, on representation to this effect being made, the embargo was 

 temporarily lifted from Canada under the conditions exacted. (See circular No. G, 

 entitled " Regulations under the Destructive Insect and Pest Act governing the 

 Importation, Sale, Shipment, and Exportation of the Common or Irish Potato [Solanuin 

 iuherosum L.)." 



