604 FUNDAMENTALS OF FRUIT PRODUCTION 



trees in the orchard. "^^^ "Tree-census observations in Navel orange orchards 

 in California show a general average of about 25 per cent, of trees of diverse 

 strains, most of which are inferior to the Washington as regards both the amount 

 and the commercial quahty of the fruit." 



"Occasional limbs have been found in such trees [Washington strain] pro- 

 ducing typical Golden Nugget fruits consistently from year to year during the 

 entire period of observation. . . . The variation in the amount of annual 

 crops produced by a given series of individual Washington Navel orange trees 

 is relatively uniform throughout the series each year. That is, the highest 

 producing trees in any one year are in general the highest producing ones each 

 year, and the lowest ones remain at the bottom of the list continually. Indi- 

 vidual trees are relatively very stable over a series of years in the character and 

 the amount of their production. . . . Suckers, or unusually vigorous non- 

 bearing branches have been used almost universally for this purpose. This 

 practice has led to the propagation of a continually increasing proportion of 

 trees of those strains producing the largest amount of sucker growth. Inasmuch 

 as such trees are usually light bearers and produce inferior fruits this practice 

 has been unfortunate and is the direct cause of the presence of the large propor- 

 tion of unproductive trees found in many orchards. Fruit bearing bud wood has 

 been selected from limb variations occurring in trees of the Washington or other 

 strains and in several hundred cases where the growth from these buds has 

 fruited every selection has come true."^^^ 



With such fruits pedigreed is to be preferred to common stock for it 

 represents definite types of strains that run true, when there is consider- 

 able uncertainty as to what to expect from the general run of unselected 

 stock. Perhaps "pedigreed" is an unfortunate term to apply to such 

 selected stock; it is rather "improved" stock. 



Some Results with Apples. — Hedrick^^ represents fairly well one school 

 of opinion when he says, concerning "pedigreed" apples: 



"At the very outset it must be pointed out that the seeming analogy between 

 plants propagated from buds and cions and those grown from seeds has given a 

 false simplicity to the fact and has led many astray. Analogy is the most 

 treacherous kind of reasoning. We have here a case in which the similarity of 

 properties is suggested but the two things are wholly different upon close analysis. 

 In the case of seeds there is a combination of definite characters, in the offspring 

 from two parents. Since the combinations of characters handed down from 

 parents to children are never the same, individual seedhngs from the same 

 two plants may vary greatly. On the other hand, a graft is literally a ' chip of the 

 old block' and while plants grown from buds may vary because of environment 

 they do not often vary through heredity. . . The Geneva Station has an 

 experiment which gives precise evidences upon this question of pedigreed stock. 

 Sixteen years ago a fertilizer experiment was started with 60 Rome trees propa- 

 gated from buds taken from one branch of a Rome tree. Quite as much varia- 

 tion can be found in these trees from selected buds as could be found in an orchard 

 of Romes propagated indiscriminately and growing under similar condition. 

 Data showing the variations in diameter of tree and in productiveness . . . 



