234 MASS. EXPERIMENT STATION BULLETIN 280 



The average growth of the trees during the four years they have been in the 

 orchard is as follows: 



Increase in Trunk Diameter in Four Years 

 (Own-rooted trpes=100) 



Stocks 4, 12, and 16 seem to be standard stocks, while the others dwarf these 

 two varieties in varj'ing degrees. The difference between the two varieties when 

 worked on Stock 1 is exceptional. Stocks 2 to 9, inclusive, are represented in 

 small numbers, which may well explain the differences which appear. 



Tree Character of Fruit Varieties. (J. K. Shaw and A. P. French). Fur- 

 ther studies of nursery trees of different varieties of tree fruits have been made 

 in connection with the certification work of the Massachusetts Fruit Growers' 

 Association and with inspection work in other nurseries. Photographs 

 showing the varietal characters of one and two year trees as grown in the station 

 nursery have been made. This work will be continued next year and should 

 furnish material for a publication setting forth variety characters better than 

 can be done in any other way. A revision of Bulletin No. 208 was published dur- 

 ing the year as Bulletin No. 274, "The Identification of Apple \'arieties from 

 Non-Bearing Trees." 



The Genetic Composition of Peaches. (J. S. Bailey and A. P. French). 

 In the spring of 1931 a number of seedlings were crossed and selfed to get an 

 F, generation. \'ery few fruits were obtained because of unfavorable weather 

 conditions following the hand pollinations. 



The study of tree and fruit characters of the seedlings was continued. The 

 results are in agreement with the statements made last year. 



Several times during the winter the temperature fell below^ enough to kill 

 some of the fruit buds. Part of the seedling orchard experienced a temperature 

 of -18° F. Some of the fruit buds survived. More time, therefore, was given to 

 determining the percentage of buds killed under outside conditions and less time 

 to W'Ork with the freezing apparatus. 



Testing Methods of Pruning. (J. K. Shaw). This project with young 

 bearing apple trees has been continued as usual. No new- developments have 

 app(>ared. Under the conditions of this test no marked benefits from pruning 

 are apparent. This should not be interpreted as moaning that bearing trees need 

 not be pruned. Under conditions of good orchard management light pruning is 

 probably desirable, but heavy or even moderate pruning seems to interfere with 

 maximum production with no very distinct improvement in quality. 



Effect of Pruning Bearing Apple Trees. (\V. L. Cutler). The fifth year 

 of this experiment in an orchard over forty years old was continued with no 

 new trends appearing. This was the off -bearing year, and the crop was less than 

 one-half of that of 1930 and somewhat scattered among the different varieties 

 and trees. 



