84 JOURNAL OF THE RQYAL HORTICULTURAL SOCIETY. 



are liable to interfere with experiments even when they are carried 

 out on apparently uniform soil within a small area. 



The variety grown was ' Arran Chief,' a variety of vigorous growth, 

 making tall tops, but fairly resistant at present to the common potato 



Potato Spacing Experiments. Sq. Rod Yields Compared. 



Spacing . . 18* x 9* 

 Area each plant ij sq. ft. 



lb. oz. 



Ware and seed . 273 6 

 Chats - . . 41 2 



18" x 12* 

 If sq. ft. 



lb. oz. 

 279 8 

 28 6 



18* x 15* 



if sq. ft. 



lb. oz. 

 252 8 

 32 9 



18' x i8 # 



■z\ sq. ft. 



lb. oz. 

 225 4 

 19 13 



Total . . . 314 8 



307 14 



285 1 



245 1 



Aver, yield . 1 4J 

 No. of plants . 242 



I II 



182 



1 is* 

 145 



121 



Spacing . . 24* x 9* 

 Area each plant i£ sq. ft. 



lb. oz. 



Ware and seed . 261 0 

 Chats . 43 0 



24* x 12' 

 2 sq. ft. 



lb. oz. 

 250 O 

 22 O 



24' x 15' 



2jsq. ft. 



lb. oz. 

 251 O 

 29 8 



24* x 18* 

 3 sq. ft. 



lb. oz. 

 230 8 

 17 10 



Total . . 304 0 



272 O 



280 8 



248 2 



Aver, yield . 1 io£ 

 No. of plants . 182 



2 0 

 136 



2 0 

 109 



1 1 



91 



Spacing . . 30* x 9* 

 Area each plant if sq. ft. 



lb. oz. 



Ware and seeds . 247 10 

 Chats . 32 10 



30" X 12* 



i\ sq. ft. 



lb. oz. 

 243 0 



20 8 



30* x 15* 

 3i sq. ft. 



lb. oz. 

 225 4 

 22 4 



30* x 18* 

 3* sq. ft. 



lb. oz. 

 227 8 

 15 10 



Total . . 280 4 







263 8 



247 8 



243 2 



Aver, yield . 1 14 J 

 No. of plants . 145 



109 



85 



73 



Spacing . . 36" x 9* 

 Area each plant 2 J- sq. ft. 



lb. oz. 



Ware and seed . 232 0 

 Chats . . 27 12 



36' X 12* 



3 sq. ft. 



lb. oz. 

 230 4 

 21 12 



36' x 15' 

 3* sq. ft. 



lb. oz. 

 227 O 

 15 6 



36' x 18* 

 4i sq. ft. 



lb. oz. 

 2l6 O 

 14 8 



Total . . 259 12 



252 0 



242 6 



230 8 



Aver, yield . 2 i\ 

 No. of plants . 121 



2 I2l 

 91 



3 5h 

 73 



3 "J 

 61 



blight due to Phytophthora infestans. The stock had come from Scot- 

 land in 1 91 7 and had been grown once at Wisley. The tubers selected 

 for seed were of uniform size (about 3 oz.) and were sprouted in a light 

 place before planting. They were all planted on May 8, 191 8, at a 



