404 Summary of Agricultural Experiments. [Aug., 



4. — Seed potatoes obtained early in the year and sprouted before being 

 planted give a larger yield than those obtained late and planted direct 

 (i.e., unsprouted) from bags. It is important to keep the first formed 

 sprouts, as they are the strongest, and appear above ground in the 

 shortest possible time, thus allowing a longer season of growth. 



5. — The increased yield from seed bought early in the year will repay 

 the extra labour incurred by its early arrival upon the farm, and will 

 at the same time allow of a substantial profit, as, on the average, the 

 crop is increased by more than two tons of large tubers per acre by the 

 use of sprouted seed. 



Planting Potatoes (Aberdeen College of Agriculture, Leaflet No. 6). — 

 This leaflet gives the results of field trials carried out on a large number 

 of farms during the four years 1905-8 for the purpose of ascertaining 

 the effect of sprouting seed potatoes in boxes before planting. In 1905, 

 the average gain by sprouting was 1 ton 18 cwts., in 1906 it was 1 ton 

 9 cwts., in 1907 it was 2 tons, and in 1908 it was 2 tons 4 cwts. The 

 average percentage of small and diseased potatoes was also less with 

 the sprouting system, and it may fairly be assumed that the practice 

 is one which will prove profitable in the majority of cases. The method 

 is described in the Board's Leaflet, No. 173. 



Planting Potatoes (Edinburgh College of Agriculture, Bulletin 17). — | 

 The experiments reported in this Bulletin as regards the manuring and 

 the selection of varieties of potatoes have been summarised in this 

 Journal (July, 1909, pp. 314 and 316). Another point dealt with was 

 the advantage of cut as compared with whole sets. Six tests were 

 made with three varieties, the sets being of equal weight and number. 

 In every case the cut sets yielded a smaller proportion of undersized 

 tubers than the whole sets, and in five cases cutting the large sets gave 

 more ware up to 50 cwts. per acre. The total crop, however, was some- 

 times greater and sometimes smaller with the cut sets. 



Another experiment dealt with the size of the seed. It is usual to 

 dress the ware over if-in. riddles, and then dress for seed what is left 

 by means of if-in. riddles. Many of the sets obtained in this way 

 are found to weigh about 1 oz. This trial, therefore, was undertaken 

 to ascertain whether it would be an improvement to use slightly larger 

 sets. The method adopted was to take seed dressed with the if-in. 

 riddle, and to divide it into " tops " and " tails " by means of a if-in. 

 riddle. This was done with four varieties, and in every case the " tops " 

 gave the greater yield, the increase varying from about 5 cwts. up to 

 30 cwts. per acre, the average amounting to about 17 cwts. This point 

 will be subjected to further trial, but the results so far indicate that the 

 i|-in. riddle is on the small side, and that the use of one, say, if in., 

 or if in., would be an improvement. 



Considerable diversity of opinion exists amongst potato-growers as 

 to the most profitable distance apart to plant sets in the rows. Three 

 trials were undertaken to test this, the distances being 12 in., 14 in., 

 16 in., and 18 in. The largest crop was in each case obtained by plant- 

 ing at 12 in. apart, there being a gradual falling off in yield as the 

 distance widened. 



Planting Potatoes (Herts. C.C. Leaflets 6 and 7). — The experiments 

 as regards manuring and varieties recorded in these leaflets have been 

 summarised in this Journal (July, 1909, pp. 313 and 315). 



