128 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 
I 
24" x 12" = 2 sq. ft. 
lb. oz. 
Ware and seed . 227 12 
Chats . . 28 9 
2 
24" x 15* = sq. ft. 
lb. oz. 
Ware and seed. 199 1 
Chats . 22 11 
24" x 18" = 3 sq. ft. 
lb. oz. 
Ware and seed .184 8 
Chats . . 15 11 
Total . . 256 5 
Total . . 221 12 
Total . . 200 3 
Average plant . 1 14I 
Average plant . 2 1 
Average plant . 2 7 
A 
30" x 12" = 2| sq. ft. 
lb. oz. 
Ware and seed . 187 11 
Chats . 23 0 
5 
30" X 15" = 3| sq. ft. 
lb. oz. 
Ware and seed .198 1 
Chats . . 21 13 
6 
30" x 18" = 3I sq. ft. 
lb. oz. 
W T are and seed . 202 6 
Chats . 17 0 
Total . .219 6 
Average plant . 3 4 
Total . . 210 11 
Total . . 219 14 
Average plant . 2 0 
Average plant . 2 9 
7 
36" x 12" = 3 sq. ft. 
lb. oz. 
Ware and seed. 181 13 
Chats . 20 5 
8 
36" x 15" = 3! sq. ft. 
lb. oz. 
Ware and seed .172 2 
Chats . 12 3 
9 
36" x 18" = 4! sq. ft. 
lb. oz. 
Ware and seed. 164 0 
Chats . . 1 5 1 1 
Total . . 179 11 
Total . . 202 2 
Total ^ .184 5 
Average plant . 210 
Average plant . 2 4 
Average plant . 3 4 
It will be seen that, within the limits of spacing used in this series 
of experiments, two points stand out quite clearly : 
1. The greater the space given to the individual plant the greater 
the yield of that individual is likely to be. 
2. The greater the number of plants on a given area the greater 
the yield from that area will be. 
It follows that in order to produce the greatest yield from a given 
area, planting of potatos must be somewhat close rather than wide 
(i.e. within the limits shown by this experiment); but if it is desired 
to raise a large quantity from a small number of seed-tubers the tubers 
must be planted far apart. 
VI. Effect of Time of Planting on Yield. 
Sprouted seed tubers of approximately equal size of the same 
stock of the variety ' Windsor Castle/ grown at Wisley in 191 6, were 
planted on five different dates, viz. April 4, April 16, May 1, May 15, 
June 1 respectively. They were planted in rows 2 feet 6 inches apart 
and 18 inches apart in the rows, and were grouped in sets of 
sixty plants, twenty in a row, each group being duplicated, so that 
