ANNUAL REPORT, 1941 87 



Tree Characters of Fruit Varieties. (J. K. Shaw, A. P. French, O. C. Roberts, 

 and L. Southwick.) This project has been carried on for many years. As new 

 varieties are constantly appearing there seems to be no end in sight of a need for 

 such work. Varieties of apple, pear, plum, cherry, and peach desired for observa- 

 tion are maintained in the nursery. The usual inspection of nurseries for trueness 

 to name was made, but certification under the auspices of the Massachusetts 

 Fruit Growers' Association was discontinued this year. If trees are kept true to 

 name in the nursery row, the chances of a grower getting trees not true to name is 

 sma!l; and it was felt that the relatively' expensive certification was not worth 

 while. 



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

 attention was gi\x*n to the inheritance of blossom characters. Results indicate 

 that blossom t^'pe (showy or nonshowy blossoms) is controlled by one pair of 

 genes (Shsh), with the nonshowy type dominant, and that blossom size is con- 

 trolled by one or more other pairs of genes. This work will be reported in the 

 Proceedings of the American Society for Horticultiiral Science. 



Comparison of Cultivation and Sod in a Bearing Orchard. (J. K. Shaw.) This 

 project was continued as in the past but a new project referred to elsewhere was 

 started on one of the complete-fertilizer plots. Another plot is used for the 

 mulching experiment and is referred to under that project. The remaining five 

 plots continue to indicate that on this soil a balanced fertilizer is now necessary. 

 It suggests that the fruit grower who is using nitrogen alone as a fertilizer should 

 watch for indications of a shortage of other elements. As long as nitrogen alone 

 results in satisfactory performance of the trees it should be continued, but any 

 symptoms of shortage should be promptly diagnosed and the deficiency supplied. 



Comparison of Cultivation and Heavy Mulching for Apples. (J. K. Shaw.) 

 The two small plots where heavy mulching was begun in 1922 continue as reported 

 last year. The mulch material decays rather slowly and bids fair to last several 

 years without additional applications. The trees continue to grow and bear 

 well although grass grows vigorously up through the mulch. 



Additional mulch was applied to plot 3 in the cultivation-sod orchard. The 

 material was weighed this year. It amounted to 4225 pounds applied to 10 

 trees or about 5j^ tons per acre. Probably this amount applied annually is more 

 than is economical. Rootlets are much more abundant just beneath the mulch 

 than in surface areas under cultivation or sod. Doubtless there are three condi- 

 tions that would favor such root development: (a) better and more uniform 

 moisture supply, (b) more readily available nutrients, and (c) better aeration. 

 The growth on these trees this summer was remarkably good and the crop was 

 the largest of any of the seven plots in the orchard. When the mulching was 

 begun four years ago nitrogen must have been very low and the cover crop was 

 negligible. The mulch was applied to almost bare soil. Yet there never have 

 been any signs of nitrogen depression following these liberal applications of waste 

 hay. The trees immediately improved in vigor and production and continued 

 to do so in successive years. No fertilizer, other than the mulch, has been ap- 

 plied for twenty years. 



The two plots in the Mcintosh clonal stock orchard received additional mulch 

 this second year. . The material weighed 13,300 pounds or about 6H tons per 

 acre. This again is an excessive amount and will be reduced in the future to see 

 if equally satisfactory results can be obtained. The rest of the orchard was seeded 

 in August 1940, to a mixture of red, alsike, and Ladino clovers. A good stand was 

 obtained and now consists mostly of Ladino clover. The clover areas (about two 

 acres) were fertilized with 150 pounds nitrate of soda and 200 pounds nitrate of 



