270 CALIFORNIA FRUITS: HOW TO GROW THEM 



by the fact that the Wickson, a Burbank triflora-simoni hybrid, is the 

 leading shipping plum of California, and shipping plums are chiefly 

 grown in the central and northern regions of the State. Other notable 

 Burbank plums of recent introduction will be included in the descrip- 

 tions of varieties at close of this chapter. 



SOILS AND STOCKS FOR THE PLUM 



With the plum, as with the apricot, the subject of soils and stocks 

 are intimately related, but the whole matter has been wonderfully 

 simplified by the experience of the last few years. This relief has 

 come through the adoption of the myrobalan, or cherry plum (prunus 

 myrobalaria) has a general all-around stock for plums and prunes. 

 Before this practice was taken up the effort to grow the plum on its 

 own roots generally resulted in getting- an orchard full of suckers, and 

 to avoid this, plums were worked on peach roots wherever this root 

 would succeed in the soil to be planted. But some varieties of plums 

 do not take kindly to the peach, and then "double working" (putting 

 first on the peach a plum which is known to take well and then on that 

 plum wood the variety desired) was followed. The use of the myro- 

 balan does away with the suckering nuisance, and the need of double 

 working. 



There was considerable discussion a few years ago as to what is 

 the true myrobalan, and it must be acknowledged that some of the 

 refined distinctions formerly claimed have been abandoned. Seedlings 

 grown from the seed of the myrobalan vary as do other fruit seedlings, 

 both in fruit and in foliage and habit of trees, and perhaps this fact 

 has given rise to the distinction between "true" and "false" myrobalan, 

 so-called. Practice has proceeded without much reference to the 

 discussion, and our nurserymen now have large, thrifty myrobalan 

 trees from which they secure their seed supply. Growing stock 

 from myrobalan cuttings is but little practiced. The myrobalan is now 

 the accepted plum stock for California, except in light, alluvial, well 

 drained soils, where, for the French prune, peach or almond may be 

 preferred. Though described by some authorities as a dwarfing stock, 

 it is found to be sufficiently free growing in California to suit all 

 purposes, and to form a good foundation for full standard trees, though 

 the peach and almond roots in proper soils give a quicker and greater 

 growth. Experience has shown that the myrobalan root thrives in 

 this State both in low, moist, valley lands; in comparatively dry lands; 

 if not too light and leachy? and in stiff upland soils. 



In some soils especially adapted to the peach, peach roots are 

 preferred as stock for the French prune, but, as already said, all plums 

 can not be worked directly on the peach root, the Robe de Sergeant, 

 Columbia, Yellow Egg, Washington, and Sugar Prune, for example. 

 Sometimes the bud or scion may make a large growth, but the two 

 woods do not unite, and the trees break off sooner or later. 



Some work the plum on the apricot root, and report success when 

 the soil suits the apricot root, and the gophers do not get at it. But it 



