LOCALITIES FOR PLUMS AND PRUNES 269 



is sufficient moisture in the soil, good plums can be grown. The tree 

 is quite hardy, but in situations open to the sweep of the winds there 

 has been found to be decided advantage in belts of sheltering trees for 

 protection. At some points subject to direct coast influences, there is 

 sometimes loss by cracking of the fruit. It is seldom encountered in 

 the interior valley, except near the rivers or in draws where the damp 

 coast air makes its way through. It seems to be worst where there are 

 marked differences in atmospheric humidity within short periods of 

 time. Where the percentage is quite uniformly high or low there seems 

 to be less trouble. Some years conditions usually restricted to more 

 exposed coast situations prevail in the interior valley, and the result is 

 unusual prevalence of mildew and other moist fungi and cracking of 

 fruit also, though they have no relation to each other except that the 

 same conditions favor both. Only certain varieties are thus affected, 

 and they can be avoided where the trouble is found to exist. 



It was for a long time held that southern California was not 

 adapted to the growth of the plum, but the experience of the last few 

 years has shown that the conclusion was too broad. The "French 

 prune" demonstrated its success adjacent to the Coast in Santa Barbara 

 County, and elsewhere, in the low, rich lands of the Santa Ana Valley, 

 of Orange County, in the interior at various points on the rim of the 

 San Gabriel Valley, in Los Angeles County, notably at Pomona, and 

 still farther inland in the San Bernardino Valley, but the Southern 

 California prune product is small because the land and water can be 

 more profitably used for other fruits. There is, however, difficulty in 

 some dry uplands where the tree is shy in fruiting and subject to serious 

 gumming ; but this is encountered locally in all parts of the State. Irri- 

 gation does not always overcome these troubles, and .yet, no doubt, the 

 arrangement of proper moisture conditions is important. The tree 

 should be helped to make one good growth and to ripen its wood in 

 the fall. To have growth checked by drouth and a second start made 

 later in the season is not desirable. 



Still it must be admitted that prune planting in the interior, pro- 

 ceeding with such rapidity, has encountered some soils and situations 

 in which bearing has not been altogether satisfactory. New planters 

 should confer with older residents before making investments in prune 

 planting in interior valleys and foothills. 



All the foregoing observations are based upon the behavior of 

 plums of European origin ; descendants of the prunus domestica. One 

 of the grandest contributions to the extension of the range of the plum 

 in California was the introduction of the Asiatic species, prunus 

 triflora and simoni. Varieties of these species directly introduced or 

 locally developed by Burbank and others, have proved productive in 

 places where the domestica varieties were abandoned as shy or sterile. 

 To estimate the value of these varieties one has only to visit the home 

 fruit gardens of southern California or inspect the fruit stands of Los 

 Angeles which are continuous exhibits of fine specimens of these 

 varieties in their seasons. Even in places where the domestica varieties 

 are largely grown the Asiatic varieties are also prominent as is shown 



