DIVISION OF BOTANY 483 



SESSIONAL PAPER No. 16 



i. Bins, pits, cellars should be cool, not above 40 degrees at any time, and good 

 ventilation should be provided. 



5. The stored tubers should be overhauled at intervals, and any potatoes showing 

 signs of disease should be removed. 



If the above suggestions are carried out not only will the losses in storage be 

 wholly prevented, but the chances of carrying certain diseases over to next year, by 

 the use of unsound tubers, will be eliminated. 



EXPERIMENTS IX GROWING POTATOES 



The Director of Experimental Farms instructed the Dominion Botanist to 

 take charge of tbe growing of four leading varieties of potatoes on four acres of land, 

 principally for the purpose of producing ' as large and as profitable a crop as possible; 

 free from disease or as free from disease as possible under conditions such as exist 

 in Canada to-day.' 



The opportunity for demonstrating the effectiveness of spraying potatoes under 

 field conditions was very welcome and after laying out the experiments, the first 

 results are herewith reported. The practical work concerning planting, cultivation 

 and harvesting was carried out under the direction of the Farm Foreman, Mr. D. 

 D. Gray. 



The plan of the experiment was briefly this : — 



THE LAND. 



Four statute acres of land in field E 1 of the Agriculturist's part of the Farm 

 were used. The land was the year before under sod and had not been used for 

 potatoes previously. Like all the land of the Central Farm, the soil varied in some 

 parts, but was generally speaking fairly even and in suitable condition for potato 

 growing. It was divided into four lots of one acre each, the dividing lines running 

 cast and west. 



VARIETIES, QUANTITY USED, DATE OF PLANTING, ETC. 



The following four varieties were chosen: Carman No. 1, Irish Cobbler, Gold 

 Coin, and Early Delaware. Date of planting, May Hist. Planted by machine, single 

 sets, 14 inches between sets, not more than five inches deep. Rows, partly 30, partly 32 

 inches apart. 



SPRAYING FOR POTATO BEETLES AND DISEASES. 



As soon as the plants were about six inches high, spraying was begun. A four-row 

 double cylinder sprayer was used throughout the experiments. The four-row spraying 

 attachment as sent out by the manufacturers did not give good satisfaction; the 

 spray pump, however, was found very satisfactory. We have carefully studied the 

 mechanics of this attachment and suggested a number of improvements to the manufac- 

 turers which they have agreed to carry out, and next year the new attachment will 

 be used. The objections to the present attachment were that the nozzles could not 

 possibly spray the plants from every side. Thus some rows were only half sprayed, 

 mid the potato beetles, which were present in countless numbers, fed ravenously on 

 tihe unsprayed portions of the plants and did considerable damage. 



The spray solutions used were: — 



No. 1 — 6:4:40 Bordeaux mixture + 5 lbs. of Arsenate of lead. 

 No. 2— G:4:40 " " +5 lbs. Arsenite of soda. 



No. 3—5:5:40 " " +5 lbs. Arsenate of lead. 



No. 4—5:5:40 " " +5 lbs. Arsenite of soda. 



16—314 



