156 



MASS. EXPERIMENT STATION BULLETIN 238 



process of thinning out the top. This table shows something of the manner in 

 which heading reduced fruit bearing. 



Tablk 5. — Development of Growth Points, May 1922 



Leaf Total No. of 

 shoots growth points 



5.1 

 4.3 



13.8 

 2.4 



39.4 

 40.5 



32.3 

 39.6 



Efect 011 Bloom and Yield 



This orchard has not produced much fruit. None has been borne by the 

 Northern Spy trees, and the product of the Kings is negligible. The first crop 

 of the other varieties was in 1922 and there has been a light to moderate crop 

 each year since. The Mcintosh trees have naturally borne the most, averaging 

 over 41/2 bushels per tree for the four years' total crop. The average percent- 

 age of bloom and the average yield per tree for the four years are shown in 

 Table 6. The most significant fact brought out is the effect of annual cutting 

 back. It has decreased bloom in every case, and decreased yield in all cases 

 except the globular Mcintosh. Probably the differences between the different 

 tyi^es of pruning, not involving cutting back, and including the unpruned trees, 

 are of no great significance. While the tops of the unpruned trees are pretty 

 thick, no marked inferiority of the fruit in either size, color or quality has yet 

 appeared. 



Table 6.— Bloom and Yield, 1922-1925, inclusive. 



Summary of Experimental Studies 



This section is based in part on the data and observations presented in this 

 bulletin and in part on a previous publication." 



All things considered, probably a system of pruning similar to the modified 

 leader type is most desirable. 



' Mass. Agr. Expt. Sta. Bui. 226, 1926. 



