THE NEW CRAFT OF MAKING PLANTS TO ORDER 



III. WHAT CAN WE DO TO INCREASE AND BETTER THE FRUIT CROP? 



J. L. COLLINS 



Dept. of Genetics, California Agricultural Experiment Station 



Editor's Note: — This is the concluding article in Doctor Collins' series in which he has discussed the methods of modern science as applied to the improve- 

 ment of our cultivated plants. It has been an attempt to tell the non-technical gardener something of what has been going on in the advance lines of horticulture. 

 The whole subject of breeding definitely toward preconceived ideals is so new that very little is known about it in a popular way. Hence this series of articles. 



BVIOUSLY increased production of our fruit trees 

 would take on an interest almost of national character, 

 but equally plain it is that such results cannot be pro- 

 duced in any instantaneous, miraculous way. There 

 Aladdin's lamp for the plant breeder. Temporary in- 

 creases may be secured by the application of fertilizers, but that 

 is only a passing acceleration of production. The thing sought 

 is an inherent ability of the plants themselves, by certain changes 

 within, for the constant production of more and better fruits. 

 This desired goal may be approached by two more or less inter- 

 related paths, viz: (a) the improvement of existing varieties; and 

 (b) the production of entirely new varieties. 



Making Present Varieties Better 



MANY orchards might be made to produce a greater net 

 return by the process of weeding out low producing trees 

 and replacing them with high producers. It costs as much to 

 maintain a low producing tree as it does a high producing one. 



A COMPARISON IN PRUNES 



A single fruit of the Little French Prune variety compared with one 

 of the Coates No. 1418 French Prune which originated from it as a 

 bud sport. The new, larger variety will, of course, soon replace its 

 parent. Fruit growers should always be on the watch for bud 

 sports and mutations of this kind. Photo actual size 



A DAHLIA MUTATION 



The flower on the left is representative of an ordinary garden variety. 

 The one on the right is a "mutant" showing a distinct change in 

 shape and size of the petals. The color was also slightly lighter 

 than that of the normal flowers. Changes of this kind are the 

 starting points for the production of new horticultural varieties 



In many cases where orchard records have been kept it has been 

 found that some low-producing trees are maintained in an 

 orchard at an actual loss! 



Weeding out undesirable trees is no more expensive of time 

 or trouble than the weeding out of the low milk producers from 

 a herd of dairy cows, which every modern dairyman does after 

 getting the production record of each cow in the herd. Simi- 

 larly, by recording the harvest of individual trees for three or 

 more years and computing the cost of orchard upkeep on a per- 

 tree basis it is possible to locate the profitable and unprofitable 

 trees. For instance, records in a number of California citrus 

 orchards, kept by A. D. Shamel, furnish evidence of a very 

 definite nature, and "drone" trees are eliminated either by top- 

 working them to other more productive varieties or through 



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