16 UNIV. OF N. H. AGR. EXPERIMENT STATION [Bulletin 216 



The data presented in Table IV are somewhat irregular in regard to the 

 effect produced by spraying with Ume-sulphur 14 days after the calyx. WTien 

 Bordeaux mixture was used for the pre-pink, pink and calyx sprays, or for the 

 pre-pink and calyx sprays, lime-sulphm- applied 14 days after the calyx spray 

 was obviously of no value; but when lime-sulphur was used at the pre-pink, 

 pink and calyx sprays, an apphcation of the same fungicide 14 days after the 

 calyx produced very marked results. The per cent of russeted fruit on all the 

 trees sprayed with Bordeaux mixture was high, even an application of this 

 fungicide at the pink stage being injm-ious. 



In the experiments on Mcintosh which have been carried on since 1921 the 

 object has been particularly to study the comparative value of Bordeaux mix- 

 ture and lime-sulphm- solution for the control of scab. WTien the experiments 

 were first begun, the non-sprayed trees were so badly infected with scab that no 

 marketable fruit was produced; but in 1923 while the fruit was quite scabby the 

 greater part of it was marketable. In 1921 and 1922 the control obtained by 

 the use of lime-sulphur was not so good as that given b}^ Bordeaux mixture, but 

 in 1923 under a less severe incidence of scab the protection afforded by lime- 

 sulphur was as satisfactory as that given by Bordeaux mixture. 



Effect of Climate on Productiveness of Potatoes. 



In experiments carried out in 1921 and 1922 with the Green Mountain 

 potato it was found by O. Butler that seed stock grown at East Kingston was 

 not so productive the second year as the first when compared with the same 

 strain gi-own in Maine, and it was decided to test the effect of early harvesting 

 on productivity. Seed potatoes were therefore harvested in 1922 ninety, one 

 hundred, one hundred and ten, and one hundred and twenty-three days — full 

 season — after planting and kept over winter in cold storage. The seed was 

 planted in 1923 in alternate rows with stock of the same strain grown in Maine 

 in 1922. The yields obtained make possible no definite conclusion. They 

 were as follows : 



Table V. 



90 days stock .... 

 100 days stock. . . . 

 110 days stock .... 

 123 days stock .... 

 Maine grown stock. 



Yield per acre. 



363.26 bushels 

 344.43 bushels 

 358.77 bushels 

 366 . 07 bushels 

 378.50 bushels 



In 1921 and 1922 the East Kingston grown stock not only yielded poorly, 

 but the plants were not sufficiently free from degeneration diseases to meet 

 certification requirements; whereas in 1923 all the East Kingston grown stock 

 met these requirements. 



Spraying Potatoes. 



The following potato experiments were carried out by O. Butler during the 

 year: 



