20 UNIV. OF N. H. AGR. EXPERIMENT STATION [Bulletin 250 



tiires were used with the following ratios copper sulphate to quick lime: 

 1 :02 (neutral), 1 :05, 1:1, 1 :2, 1 :4, 1 :6. A neutral mixture or a very slightly 

 alkaline wash is the only one that can safely be used. 



The cause of the injury is due to the formation of cupric cyanide which 

 decomposes with the liberation of cyanogen in the case of those mixtures 

 which are toxic when the foliage is not wetted, or to the formation of an 

 alkaline double cyanide in the case of the mixtures which show toxicity 

 when wetted or increased toxicity on being wetted. 



Sunflower, tomato, bean, cucumber, castor oil and potato plants were 

 used. Results are discussed in Sc'entific Contribution 25. (Adams Fund.) 



MORE SPRAYS FOR APPLE SCAB 



In 1928, for the first time in several years, four sprayings for apple scab 

 were found by O. Butler to be essential to commercial control. Control 

 probably could have been improved by a fifth spraying. The production 

 of A-grade fruit from the trees sprayed three times was 25 per cent, com- 

 pared to 66 per cent from the trees sprayed four times. Lime-sulphur 

 solution, 1 to 50, was used throughout, and at the prepink and calyx ap- 

 plications calcium arsenate was added for insect control in one series of 

 experiments at the rate of l\4 pounds to 50 gallons and in the other at ^4 

 pound to 50 gallons. Both strengths of calcium arsenate gave satisfac- 

 tory insect control. (Hatch Fund.) 



EUROPEAN CORN BORER STRAINS MEET 



The two-generation phase and the one-generation phase of the Euro- 

 pean corn borer are now making contact in the western part of the state, 

 finds W. C. O'Kane. The former phase occupies the generally infested 

 area of New Hampshire, having spread from the original infestation in 

 Massachusetts. The one-generation phase originated near Schenectady, 

 N. Y., and has spread across eastern New York and southern Vermont. 



Although no one can predict the outcome of the contact of the two 

 phases, theoretically the population of the borer in New Hampshire might 

 become more dense if the state were infested with a vigorous, one-genera- 

 tion strain. Present evidence still suggests that the two-generation 

 tendency of the specimens now generally present in the state works to 

 their disadvantage because of the shortness of the growing season. 

 (Adams Fund.) 



BREEDING SHEEP 



Constant inbreeding over a period of 15 years, during which no outside 

 blood was introduced for seven generations, has resulted in a material 

 decrease in size of sheep. This has resulted despite a constant elimination 

 of undersized offspring from year to year. There has been no inhibition 

 of fertility, however, and the percentage of twins born in the later genera- 

 tions has increased which in part may be responsible for the decrease in 

 size due to a lack of sufficient milk to support two lambs. 



A considerable number of crosses have been made between multiple 

 nippled sheep in an effort to establish a strain which possesses four func- 

 tional nipples. While a higher milk yielding capacity seems to be asso- 



