•i in: uovrni.v 1:1 i.i.i i i v. 201 



almonds can I"' worked on this rool and grown on soils now wholly 

 unsuited to their culture. 



An interesting field Eor the improvement of nursery sine], has been 

 opened up during the past few years by the work of various investi- 

 gators in propagating from selected strains within any given variety. 

 Shamel's work with citrus fruits is an example with which all Cali- 

 fornians are familiar. Authorities on plant-breeding recognize the 

 occasional occurrence of mutations or bud-sports within a variety that 

 lead to some modification of type characteristics. These modifications 

 may be so slighl as not to be easilj recognized as a departure from the 

 original type, or they may in truth constitute a subvariety thai rep 

 resents a regrouping of varietal traits sufficiently striking to represenl 



a marked improvement on th -initial type. Probably many of our 



so-called ••improved" strains of certain varieties are merely bud-sports 

 closely resembling the parent type. 



The propagation of trees from 1l1e.se mutations is one of the sources 

 for the improvement of nursery stock that is not yel fully appreciated, 

 and both nurserymen and orchardists should give greater attention to 

 the recognition oJ desirable bud-variants. At the same time, nursery- 

 men must recognize the fact thai bud-sports are as apt to occur in the 

 descending as in the ascending scale, and should be extremely careful 

 to lake wood for budding or grafting from trees that show Hie desirable 

 characteristics of th.' variety to he propagated. In deciduous fruits 

 there seems to he less of a tendency toward reversion to a less desirable 

 type than in citrus, but probably the general principle holds good 

 with both that an appreciable improvement in nursery stock will resull 

 from careful bud selection. 



However, it is probable that the hereditary influence of bud selection 

 merely creates a tendency toward certain results, and that this tendency 

 may be wholly nullified by unfavorable environment, at least so far as 

 color, size, or fruitfulness is concerned. These characteristics are vari- 

 able, often changing in the same tree from year to year, and are so 

 dependent upon climate, moisture, culture, plant food, and pollination 

 that it is wholly unlikely that they can be controlled by any improve- 

 ment or lack id' improvement in nursery stock, although it is reasonable 

 to believe under similar conditions better results will be obtained in 

 the orchard from nurserj stock propagated from trees representative 

 of the best strains id' any given variety. 



Although main of the bi s1 horticultural authorities id' the nation do 

 not accept the theorj that lives call be "pedigreed" in the same sense 

 as live stock, the evidence is certainly sufficient to indicate that careful 

 selection ol budwood i n the part of the nurseryman is a wholly desir- 

 able practice. In connection with a selection of the best rootstocks 

 available, it represents his most important contribution to the improve- 

 ineii! of nursery stock, since he is essentially a propagator and dis- 

 seminator but rarely the creator or even the discoverer id' improved 

 varieties. 



In order that nursery stock maj !»■ improved in Hie broadest sense 

 of the word, the orchardist must be continually on the alert to observe 

 all that is desirable anion.: Nature's raw materials the chance seedlings 

 and bud-sports; the plant breeder must take the mosl desirable traits 



