3i4 Summary of Agricultural Experiments, [july, 



variety in their crops, especially where disease is prevalent. Royal 

 Kidney and King Edward VII., gave a smaller yield than the kt Dates," 

 but had the advantage of comparative freedom from disease. 



As regards the comparative merits of Scotch and Irish seed, it is 

 considered that Irish seed holds its own against seed from either the 

 North or South of Scotland. 



Manurial trials were made, but owing to the high condition of the 

 land the manures had but little effect. In four seasons out of the 

 five in which these potato experiments have been carried out in Hert- 

 fordshire, the results of the heavy dressings of dung and artificials 

 have shown a direct financial loss. The extra manures have not in- 

 creased the crop sufficiently to meet the cost of manuring, and it is 

 observed that such evidence should cause growers to pause before they 

 continue to manure so heavily on land that has been brought up to a 

 high condition of fertility. 



Variety and Manurial Trials of Potatoes (Harper Adams Agric. 

 Coll., Field Expts., Report, 1909). — A variety test was carried out with 

 a number of early, second early, and maincrop varieties, at the College 

 Farm and at a farm at Orton, both Scotch and Irish seed being used. 



A manurial trial at Walton Bank was intended to show which 

 is the best phosphatic manure for potatoes, and superphosphate gave 

 a better return than basic slag. Ground lime was applied to one plot to 

 ascertain its effect in the prevention of potato scab, but no benefit was 

 derived from its application. 



Mature and Immature Seed; Effect of Frost (Harper Adams Agric. 

 Coll., Field Expts., Report, 1909). — A small trial with immature seed 

 was made, and confirmed experiments made in previous years when 

 immature seed, obtained by lifting part of the ordinary crop early in 

 August, has always produced heavier crops than mature seed. 



The effect of frost on greened and ungreened potatoes was tested, 

 and it was found that greened seed was practically unharmed if 

 exposed to 3 or 4 degrees of frost, whereas the ungreened seed was 

 badly frosted, if not killed. When the temperature fell to 24 0 F. and 

 lower the seed was killed in both cases. 



Potato Trials (Surrey Education Com., Potato Trials, Merton, 1905 ; 

 Farnham, 1906; Chessington, 1907; Clay gate, 1908). — A number of 

 experiments have been carried out during these four years on varieties, 

 and the comparative value of Scotch and Irish seed, and of mature and 

 immature home-grown seed. 



Manuring of Potatoes (Somerset Agric. Instruction Com., Report on 

 Field Trials of Manures, 1908). — These trials were carried out at four 

 farms, but the results were somewhat irregular. It is remarked in 

 the report that there is considerable doubt whether Somersetshire 

 growers are in the habit of manuring their potato crop as heavily as 

 they might in order to get the best return. There is a good deal of 

 evidence to show that on land heavily farmed with sheep, a dressing 

 of mineral manures may be expected to give a profitable increase, 

 while on land which is less highly farmed, a dressing of sulphate of 

 ammonia and superphosphate, or sulphate of ammonia and muriate of 

 potash will give equally substantial returns. 



Potato Trials (Dorset Education Committee, Potato Trials and 

 Experiments, 1909). — These experiments were conducted on four vane- 



