50 



MASS. EXPERIMENT STATION BULLETIN 209. 



above. Individual tree records of yield were not taken, nor was any 

 separation made of the yields of that portion of the trees remaining in 

 sod. In the early years no separate record of dropped and picked fruit 

 was made, but in the last four years the picked fruit was recorded sepa- 

 rately. 

 Inches 



6 7 8. 



Mur-Mg. H.GSul. Slog-Sul. 

 Fig. 10. — Average trunk circumference by plots, cultivated Baldwin trees only 

 (Graves orchard). 



Growth Records. 



Fig. 10 shows the increase in trunk circumference of the trees in culti- 

 vation in the several plots. The growth on plot 3, the check plot, has 

 been less than on the other plots, indicating that the trees responded to 

 the appUcation of all the fertilizers by increased growth. At the beginning 

 of the experiment the trees on plot 3 were exceeded in size by those on 

 plots 4, 5, 6 and 7. In 1917, at the end of the period of fertilization, this 

 difference had increased somewhat, while the trees on plots 1, 2 and 8 had 

 grown so that the check plot then had the smallest trees of any plot. A 

 later measurement of the same trees made in August, 1921, showed that 

 the check trees were still the smallest. It is interesting to note that plots 

 1, 2 and 8 are the only plots that showed greater growth than the check 

 plot in this four-year post-experimental period. 



One seems justified in concluding that on these Baldwin trees under 

 cultivation the fertilizer applications have caused greater growth, and 

 that manure and lime-carrying fertilizers have been more beneficial than 

 those chemical fertilizers which carried no lime. 



