1378 



PLUM 



PLUM 



plow-in with the beginning of tillage in March ; for no 

 summer-growing crop can be allowed in the orchard. 

 The matter has been under investigation at the Califor- 

 nia Experiment Station for some years, and after many 

 trials of native and exotic legumes, three species of 

 European lupins (L. pilosus, var. roseus and var. 



1857. Flowers of native plums. 

 Prunus Americana on the left ; 

 P. angustifolia on the right. 

 (See page 1374.) 



1858. Fruit-spurs of a 

 Domestica Plum. 



The letters indicate the 

 termination of annual 

 growths. (See page 1374.) 



cceruleus, I/, angustifolius) , and the "hairy vetch " ( Vicia, 

 villosa ) have been found to be the most promising. From 

 numerous analyses of California soils, Professor Hil- 

 gard has found them generally well supplied with lime 

 and potash, with nitrogen and phosphoric acid not over- 

 abundant. It is, then, these latter which will have to be 

 supplied first, and such has been the advice given to 

 growers. 



As mentioned above, the Plum has few serious ene- 

 mies in California, and none which cannot be held in 

 check by spraying and other treatment. Upon the leaves 

 the Plum aphis and the canker worm have given some 

 trouble. Lately, the "peach moth" has been found at 

 work on the prune trees, but not to any serious extent. 

 The trees, too, are sometimes subject to the attacks of 

 scale inse.cts; the black scale (JJecanium olea), apricot 

 scale (L. Armeniacum), frosted scale (L, pruinosum) 

 and pernicious scale (Aspidiotus perniciosus) being the 

 most frequent; all of which, however, the California 

 fruit-grower has learned to keep in check, and in some 

 cases even to eradicate. The crown root-knot has also 

 caused considerable trouble. The cause of this disease 

 has been lately demonstrated by Tourney to be a "slime 

 mold" (Dendrophagus globosus). Relief has been se- 

 cured by cutting off the knots and painting the wounds 

 with Bordeaux mixture. 



In California some fruit is usually borne the third 

 year; in the fourth a fairly profitable crop is expected; 

 the fifth from 50 to 60 pounds per tree should be pro- 



duced, which ought to double in the sixth, and after 

 that from 150 to 300 pounds is the rule. These figures 

 apply mostly to the prunes ; many of the Plums are two 

 or three years later in coming into full bearing. From 

 200 to 300 pounds are considered the average at full bear- 

 ing in the Santa Clara valley. In some instances 600 and 

 even 800 pounds have been produced, and a 6-year-old 

 tree at Visalia (San Joaquin valley) is credited with 

 1,102 pounds of fruit in one season. 



It would be impossible to enumerate a full list of the 

 varieties actually in successful cultivation within the 

 state. Such a list would probably include every note- 

 worthy variety of Domestica Plum. Many, however, 

 despite excellence of quality and flavor, are suited 

 only for home-growing, or at most for local markets, on 

 account of poor shipping qualities. For this reason 

 the mimber of varieties planted on a large scale is 

 being constantly reduced. 



Experience has demonstrated the superiority of some 

 varieties for certain climatic regions and general market 

 conditions, and these have come to be recognized as 

 standard. At the head of the list stands the Prune 

 d'Agen, the originally introduced French prune, which 

 has proved itself adapted to more varying conditions 

 than any other variety, and is therefore perhaps the 

 most generally planted variety of fruit in the state. 

 For some time its identity as the true French prune was 

 disputed ; but from authentic samples submitted to 

 them, French experts have declared it to be of the 

 true d'Ente type of the Agen district, both in botanical 

 characters and in sweetness and flavor. It is, of course, 

 used chiefly for curing. In the same category belong 

 the Robe de Sergeant, Imperial Epineuse, Silver and 

 Sugar all standard drying prune varieties. The Robe 

 de Sergeant has been supposed by some to be a syno- 

 nym of the Prune d'Agen, and is so considered in 

 France ; but in California it is grown as a distinct va- 

 riety. The fruit is larger, usually more highly flavored, 

 and has commanded higher prices in the San Francisco 

 market. The tree, however, has not proved so widely 

 adaptable, and is in disfavor in the coast valleys on 

 account of defective bearing; in the interior it is more 

 satisfactory. The Silver prune (an Oregon seedling of 

 Coe Golden Drop) is also a defective bearer in some 

 districts, and is used mostly in the preparation of 

 "bleached prunes," for which it has proved quite profit- 

 able, in some instances. It is sometimes marketed in 

 the fresh state also. The Imperial Epineuse is a recently 

 introduced French variety and is fast becoming very 

 popular. So far as tried it has proved very profitable, 

 especially in the Santa Clara valley, where many or- 

 chards have been grafted over to it. The fruit is very 

 large and handsome, and actual analysis has shown it 

 to contain 2 per cent more sugar 

 than the ordinary French. It 

 must be distinguished, how- 

 ever, from the "Imperial," a va- 

 riety very much inferior in 

 flavor and sweetness and not 

 nearly so satisfactory. Luther 

 Burbank's new Sugar prune 

 (introduced two years ago) 

 bases its claims upon superior 

 sweetness and flavor, together 

 with fair medium size. It has 

 not yet been long enough under 

 trial, however, to justify any 

 remarks regarding its merits as 

 a commercial variety. The Ger- 

 man prune, Italian (Fellenberg) , 

 Golden prune, Hungarian 

 (Pond Seedling), and Tragedy 

 are varieties sometimes used for 

 curing, but are frequently 

 shipped green as "Plums." Of 

 these the German is perhaps 

 the most extensively used. The 

 Italian succeeds well along the 

 coast in places liable to fogs 

 or sea winds, where the French is not at its best. 

 It is valuable as a late variety, and is said to dry 

 excellently, as does also the Golden, an Oregon seed- 

 ling. The fruit of the Hungarian (Pond) is very hand- 



1859. Plum rot. 

 The mummy Plums hang 

 on it-he tree all winter. 

 (See page 1374.) 





