ANNUAL REPORT, 1930 277 



All plots are in quadruplicate and received applications of phosphorus 

 and potash. 



Three series have been added with treatments of phospliorus, phosphorus- 

 potash and no fertilizer. 



Bud Mutations Among Apples and Other Fruits. (B. D. Drain and 

 W. H. Thies). A considerable nund)er of selections from bud sport limbs 

 and prospective mutation strains were made during tiie past year, and top 

 grafted into trees of bearing age. These grafts grew nicely during the 

 past season. 



Light Pruning of Young Grape Vines. (B. D. Drain). The work of 

 this project has been carried on for tliree years, with results similar to 

 those reported in 1928. Leaf area measurements sliow a much larger 

 leaf area on the light pruned vines. 



Work not on a Project Basis. As in previous years considerable work, 

 not formally organized on a project basis, has been carried on. This is 

 either of a temporary nature or is preliminary to project organization. 

 Some of it is carried on by mendiers of the department not officially mem- 

 bers of the Station Staff. 



The "Set" of Mcintosh Apples in Middlesex and Worcester Counties. 

 This problem largely disappeared in tlie season of 19;i(i when most orcliards 

 set and matured good crops. It will doubtless return in later years, for 

 the peculiarity of the variety will not change. Cooperative tests* were 

 carried out by some fourteen growers to learn something of the response 

 of their orchards to certain treatments, mostly varying fertilizer and cul- 

 tural treatments. 



Blueberry Culture. (J. S. Bailey). For several years some work has 

 been carried on with blueberries. Tiiis has been largely on propagation. 

 One of the greatest difficulties in developing blueberry culture is the High 

 cost of plants due to a lack of general knowledge of successful methods 

 of propagation. Cuttings have been grown in ordinary cold frames and 

 in a solar frame. Some progress has been made, and it is hoped that in 

 the near future it will be possible to grow plants from cuttings with good 

 success. 



A Study of the Storage of Mcintosh Under Various Conditions. (O. C. 

 Roberts in cooperation with the Agricultural Engineering Department). 

 This is the second year of this cooperative investigation of the most de- 

 sirable storage conditions for Mcintosh apples. Similar lots of Mcintosh 

 apples were stored at temperatures ranging from 45° F. to 32° F. After 

 approximately two months, samples of each lot w'ere transferred to 32° V. 

 Periodical observations and tests were made to determine the condition 

 of each lot. 



The project has been extended to include a comparison of the blower 

 type of refrigeration with the common direct expansion system with pipes 

 extending along the walls. Samples of Mcintosh apples were stored in 

 various farm storages equipped with blowers, and dujilicate lots were 

 stored in the Nashoba cold storage at Ayer. Periodical observations were 

 made and changes noted. Accurate data relative to the conditions in the 

 various storage houses were also collected at frequent intervals. 



Test of Spray Materials. (O. C. Roberts). Constant effort is being 

 made by manufacturers and experimerkt stations to discover new materials 

 and combinations which will enable tiie fruit arower to control the numer- 



