278 MASS. EXPERIMENT STATION BULLETIN 271 



ous pests in his orchard witiiout causing injury to the trees or fruit. In 

 order that the effect of these materials may be determined for Mass- 

 achusetts conditions, the Departments of Pomology and Entomology co- 

 operating have made field tests of a few of those materials which have 

 appeared to be of particular interest to Massachusetts fruit growers. 

 Details of these tests are given in the report of the Department of En- 

 tomology. 



Studies of Arsenical Residue on Apples. (O. C. Roberts). For the past 

 four years a study of the amount of arsenical residue on apples as related 

 to different spray schedules has been conducted by the Departments of 

 Pomology and Entomology and the U. S. Food, Drug, and InsecticFde 

 Administration at Boston. This experiment is discussed in the report from 

 the Entomology Department. 



Cross-Pollination and Sterility Studies with Certain Apple Varieties. 

 (F. C. Sears and O. C. Roberts). For the past six years the Pomology 

 Department has been making a study of the effects of pollination on the 

 set of fruit. Particular attention has been given to the Mcintosh, the most 

 important variety in Massachusetts. Mcintosh is practically self-sterile, 

 but appears to be a good pollenizer for other varieties. A few of the 

 most reliable pollenizers for Mcintosh are "Wealthy, Delicious, Oldenburg, 

 Ben Davis, and Cortland. 



Pruning of Northern Spy Trees. (O. C. Roberts). In 1927 the trees 

 in a small block of young Spy trees were divided into three groups. Each 

 group has since been given different pruning treatments as follows: (1) 

 Unpruned, (2) Heavy pruned, (3) Branches spread and lightly pruned. 

 These trees have just begun to bear, so data on the effect of the various 

 treatments on quantity and quality of fruit are as yet very limited. How- 

 ever, there seems to be an indication that the trees with branches spread 

 and lightly pruned are more desirable than the others. 



DEPARTMENT OF POULTRY HUSBANDRY 

 J. C. Graham in charge 



Broodiness in Poultry. ( F. A. Hays). Progress is being made in estab- 

 lishing a non-hroody and an intense broody line of Rhode Island Reds. 

 A pen of 13 hens in the non-broody line ranging in age from two to five 

 years was given access to open nests from April 20 to August 1, 1930, in 

 studies on the effect of management upon broody behavior. Non-broody 

 birds are being tested genetically for the coin])lementary genes respon- 

 sible for broodiness. 



The intense broody line is l)cing studied, with special reference to the 

 inheritance of degrees of broodiness measured by number of broody 

 periods. The non-broody and the intense broody lines are being developed 

 with special reference to uniformity in other inherited characteristics, in 

 order that the effects of broodiness may be accurately determined. 



Breeding Poultry for Egg Production. (F. A. Hays and Ruby Sanborn). 

 The mean annual production of tl»e 352 birds hatched in 1928 was 221.4 



