16 MASS. EXPERIMENT STATION BULLETIN 449 



Trials with Alfalfa Strains and Selections. (W. G. Colby.) In the spring of 

 1946 an alfalfa nursery was planted which included some 60 selections and vari- 

 eties of alfalla. Standard varieties such as Kansas Common, Oklahoma Com- 

 mon, and Baltic, and newer varieties such as Buffalo, Ranger, and Atlantic 

 were all grown with some 50 clonal selections from Nebraska and Kansas. Few 

 differences have been noted in the performance of these strains. Several of the 

 newer strains are resistant to the bacterial wilt disease but since there has been 

 no evidence of this disease up to the present, the resistant varieties have been no 

 better than any of the other varieties and selections. It is questionable whether 

 a farmer in Massachusetts is justified in paying premium prices for seed of wilt- 

 resistant varieties of alfalfa like Ranger or Buffalo unless he knows that this 

 disease is a serious problem on his farm. 



Onion Breeding. (Hrant M. Yegian.) The tendency to produce doubles is 

 found in all varieties of set type onions. Allium cepa L. The size of the set and 

 the environmental factors are considered to play an important part in the appear- 

 ance of this undesirable character. Sets over three-quarters or one inch in dia- 

 meter are more likely to produce double bulbs during favorable growing seasons 

 than the sets under three-quarters of an inch. Some variations, however, occur 

 in the double bulb frequencies in sets of different varieties but of the same size. 

 This would suggest that inherent differences in susceptibility to produce doubles 

 exist in the several varieties. 



In an endeavor to obtain a further understanding of the causes of doubles in 

 set onions, various local Ebenezer varieties were selfed and selected. In one 

 instance a double set attached together at the base was produced from the selfed 

 seed of one of the selections. Cases of double sets from a single seed are rare. 

 This newly found case strongly suggests that the character of doubles in onions 

 is probably of a genetic nature. 



DEPARTMENT OF ANIMAL HUSBANDRY 

 Victor A. Rice in Charge 



A Study of the Mineral Elements of Cows' Milk. (J. G. Archibald.) The 

 element nickel has been studied during the past year. Procedure has been the 

 same as that outlined for other elements in earlier reports. Eight cows were used 

 for the study (two each of the Ayrshire, Holsiein, Guernsey, and milking Short- 

 horn breeds); the supplement, nickel(ous) chloride, was fed at the rate of 500 

 milligrams (approximately 125 milligrams of elemental nickel) per cow daily. 

 Much of the time spent on the project was devoted to perfecting a method which 

 would detect minute traces of the element (of the order of five parts per billion 

 or less). 



The analytical work on the season's milk samples has been completed; although 

 the trend was toward an increased amount of nickel in the milk when the cows 

 received the supplement, the results were not uniform and not statistically sig- 

 nificant. This is believed to be due to imperfections of method; it is therefore 

 planned to make further study of methods and technique and to repeat the trials 

 next year. 



A Study of Quality in Roughage: Composition, Palatability, and Nutritive 

 Value of Hays as Affected by Curing, Harvesting, and Storing Procedures. 



(J. G. Archibald, M. L. Blaisdell, and H. N. Stapleton.) Twelve lots of hay 

 have been studied, involving the analysis of 50 samples. Nine of these lots were 



