262 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



80 per cent, would have produced more or less vigorous standard 

 trees. 



The stocks were then very closely examined to discover how many 

 of them showed root knots, and exhibited the possibility of easy vegeta- 

 tive propagation. The results were remarkable, and were tabulated as 

 follows : — 



Number of free stocks exhibiting adventitious roots : 



Many knots . . . . .21 

 Medium number . . . -27 

 Few . . . . . .48 



96 



At least 50 per cent, definitely exhibited this character, and many 

 of those which showed it were of a vigorous and free-growing habit. 

 The stocks were then roughly graded by their root systems into the 

 Bristol groups. Representatives of all these groups except A were 

 found, though the large majority fell in classes C (20), F (33), and 

 G (16). 



After examining the root systems and vigour of the stocks very 

 carefully, my assistant, Mr. Norman Grubb, M.S.A., prepared the 

 following correlation table, which shows the relationship betwixt 

 vigour and depth of rooting to be very different from that which was 

 popularly supposed in the past. Depth and shallowness of rooting 

 do not necessarily in themselves denote vigour and dwarfingness 

 any more than coarse or fibrous roots do. 



Correlation Table for Strength of Growth and Depth of Roots. 



{very vigorous, 

 vigorous 

 medium 

 weak 



Total, 87.* 



During last week (September 15-20) I was privileged to examine 

 a large collection of standard apple-trees of many varieties worked 

 on free stocks from the identical source whence came our collection. 

 The inequality of vigour in the stocks was most patent in the trees. 

 Many were only suitable for cordons or bush-trees, whilst others of 

 the same variety — often alternately placed — had made exceptionally 

 fine standards both in height and girth. 



Only this week a large nursery firm writes me : 



" We think you will agree that the seed sent out under the name 



* The other nine stocks ware not dug up, as they were selected for further 

 propagation. 



Roots 

 very 

 Shallow. 



Shallow. 



Inter- 

 mediate. 



Deep. 



Very Deep. 





7 



II 



2 





I 



4 





IO 



2 



2 



5 



8 



6 



3 





5 



3 



2 



2 



3 



21 



36 



20 



7 



