SOME STUDIES IN ROOT-GRAFTING. 



453 



able length of time ; but I am aware that all of them 

 may be wrong. 



The graftage of fruit stock may be analyzed as fol- 

 lows : 



1, Budding. 



2. Grafting proper, including 



a. Whole-stock-grafting, 



Piece-stock-grafting, including 

 {a) Crown-piece-grafting, 

 (/') Piece-root-grafting, or root-grafting 

 proper. 



The advantage of budding over the grafting of whole 

 roots lies chiefly in the ease and cheapness with which 

 the operation is performed. The disadvantages are 

 chiefly two : budding does not allow of deep setting in 

 order to induce roots to form from the cion itself, and 

 it sometimes makes a crook in the base of the tree. In 

 the old apple-growing regions, the first disadvantage is 

 of small account, but in parts of the west and north- 

 west it is essential to procure trees ' ' on their own roots " 

 by setting the cion deep. 



The advantages of whole-rooted trees, whether budded 

 or grafted, lie in the production of a deeper, finer and 

 more symmetrical root system than appears to be pro- 

 duced by piece-roots, and in the fact that such trees 

 make a better growth the first two or three years, due to 

 the greater force which resides in large roots. The dis- 

 advantages of whole roots are two : the greater cost of 

 the trees ; the roots are so large that they are not read- 

 ily set deep enough to allow roots to strike from the cion. 



The advantages of crown-piece-grafts over root-grafts 

 proper or piece-root-grafts are said to be many, but I 

 have not had opportunities to study this matter fully, 

 and therefore cannot express a definite opinion. It is 

 maintained by many that the crown-piece produces a 

 more vigorous growth than the lower pieces, that it is 

 hardier, and that the union with it is better. The crown- 

 piece is usually larger and stronger than lower pieces, 

 and larger and better cions are commonly used upon it. 

 But the differences in behavior between crowns and 

 roots are probably due quite as much to relative sizes 



Fig. I. Bud and Root-Graft. 



and lengths in individual cases as to difierences in struc- 

 ture and position. The notion that the "vital energy " 

 resides in the crown is, of course, untrue. 



The advantages of piece-root-grafts are these: i. 



They cheapen propagation by making two or more trees 

 from one root. 2. Allow of deep setting, in order that 

 roots may start from the cion. 3. Allow the propaga- 

 tion of rare plants which cannot be increased readily in 



Fig. 2. Three-year-old Piece-grafts and Two-year- 

 old Buds. 



other ways. 4. Accelerate or induce the rooting of cut- 

 tings by working the cutting upon a temporary root, as 

 the quince upon the apple. This is essentially the same 

 as 2, but the root is never expected to be permanent. 



The disadvantages of piece-root-grafts are certainly 

 two : I. The roots are comparatively weak the first year 

 or two, and the tree makes a shorter growth than upon 

 whole roots. 2. The roots are apt to be prongy, one- 

 sided and shallow. It is said, also, that piece-rooted 

 trees are shorter lived than whole-rooted trees, that they 

 are more apt to twist or tip over on high and hard sub- 

 soils, and that they are less hardy ; but upon these ques- 

 tions I do not care to express an opinion. 



The comparatively weak growth of piece-rooted trees 

 in the nursery is well known. The amount of growth 

 of course depends upon the amount of root used, the 

 soil and the length of the season, but as ordinarily made 

 in the eastern states, the piece-rooted tree usually does 

 not make sufficient growth the first year to form the 



