318 



POMOLOGY 



able. With fruit-trees it has been more difficult to determine 

 between variations due to environment and not of a per- 

 manent character and those which are true bud-sports. 



The following data are presented to show that decided va- 

 riations do occur between fruit-trees of the same variety 

 (clones) and between branches of the same tree, but whether 

 they are due to internal or external causes is not determined. 

 It is assumed that the trees are always comparable and that 

 there is no apparent external cause for the variation. 



Table LXXXIX 



the variations in yield of bearing apple trees as reported by 



several experimental stations in america 



Stewart, J. P. Penn. Agr. Exp. Sta. Ann. Rapt. 1911. 



