ANNUAL REPORT, 1931 233 



what by differences due to individual cans, type of can, and weight of onions 

 packed. 



A commercial brand of onions packed in enameled cans was examined five to 

 six months after canning. Only a light brown discoloration of the onions devel- 

 oped upon long exposure to the air. Very little, if any, corrosion of the can was 

 noted. Onions packed in similar cans and kept in storage for a little over two 

 years, discolored considerably upon long exposure, the discoloration developed 

 more slowly, and the ultimate color was more of a dark brown than dark olive 

 green. Unfolding the cans revealed no evidence of corrosion at the junction of 

 ends and sides or along the side seam. Discoloration of bulbs in this instance 

 could not be associated with the metal of the can, and the cause must be looked 

 for elsewhere. 



The 1931 crop of commercially canned onions, processed in plain tin con- 

 tainers, was examined two to three months after canning and showed only a 

 slight discoloration of the tinned surfaces of the can. Long exposure of the 

 onions to the air failed to produce any appreciable discoloration. Treatment 

 of the bulbs with dilute ferric chloride solution resulted in no discoloration. 

 Improved methods of canning are probably responsible for this better condition. 

 The onions were whiter and smaller in size than the Yellow Globe Danvers 

 variety. 



DEPARTMENT OF POMOLOGY 

 F. C. Sears in Charge 



The crop of peaches in the Station orchards was about as large as that of 

 1930, but the apple crop was about one-half that of last year. This is probably 

 due largely to the heavy crop of 1930. Studies of the air temperatures during 

 and immediately following bloom showed that during this period in 1930, high 

 temperatures prevailed to an exceptional degree. This may be the chief reason 

 for the heavy crop. Fluctuations in crops during the past ten years did not 

 follow the lesser differences in temperature very definitely. 



The Interrelation of Stock and Scion in Apples. (J. K. Shaw and J. S. 

 Bailey). Alternate trees in the main orchard in this project were removed during 

 the past winter. This project may be considered as finished though further 

 observations on the remaining trees may be made. Eight rows of "permanent" 

 trees were top grafted to new varieties in the spring of 1931. 



This orchard has suffered in some years from a peculiar "tip burn" of the 

 leaves. A trouble similar in appearance has been attributed to potash deficiency. 

 In this orchard it is evidently correlated with water supply of the trees The or- 

 chard has never received any potash fertilizer so it was felt that a potash defi- 

 ciency might be a factor. A strip involving two rows of trees was plowed in the 

 spring and a liberal application of muriate of potash given to one of these rows. 

 The tip burn was not prevalent in the orchard the past summer. There was no 

 evidence that potash had any influence in the limited amount that appeared. 



Efforts to propagate Mailing Stocks by mound layering were continued. 

 These are expected to yield a considerable number of rooted stocks when dug 

 next spring. These will be used to establish a new and larger stock bed. 



The orchard of Mcintosh and Wealthy on Mailing Stocks made a satisfac- 

 tory growth during the season and showed considerable bloom and some fruit. 



