PLUM 



PLUMBAGO 



2721 



and irrigation systems, therefore, has received a great 

 impetus, and the use of summer irrigation when required 

 is an established practice. 



In some of the older orchards, the need of fertilizing 

 is beginning to be felt. In a great many, the main 

 deficiency has been found to be vegetable matter, and, 

 consequently, nitrogen. The extremely fine tilth which 

 has been maintained has resulted in the destruction of 

 all natural green growth and the "burning out" of 

 the humus, and has necessitated the call for a green- 

 manure crop. This problem is rendered more difficult 

 in California by the fact that any such crop must be 

 produced during the winter months and be ready to 

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

 summer-growing crop can be allowed in the orchard, 

 unless the land is regularly irrigated and then alfalfa 

 may be grown. On non-irrigated orchards, winter- 

 growth of hardy legumes, as vetches, is undertaken. 



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. The "peach-moth" has been found 

 at work on the prune trees, but not to any serious 

 extent. The trees are subject to the attacks of the 

 black scale (Saissetia ol&e), apricot scale (Lecanium 

 corni), 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. The crown root-knot has also caused 

 considerable trouble. Relief has been secured by cutting 

 off the knots and painting the wounds with bordeaux 

 mixture. In one district the peach root-borer has estab- 

 lished itself and requires regular treatment. Thrips have 

 also done some injury to blossoms and young fruit. 

 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 to a tree should be 

 produced, 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. 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 

 six-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 in- 

 clude every noteworthy 

 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 number of varieties 

 planted on a large scale is 



3078. Fruit-spurs of a domes- being constantly reduced 

 ticaplum. The letters indicate the the head Of the list 

 termination of annual growths. stands the Prune d'Agen, 



3079. Plum-rot. The 

 mummy plums hang on 

 the tree all winter. 



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. It is, of 

 course, used chiefly for curing. In the same category 

 belong the Robe de Sergeant, Imperial Epineuse, Silver, 

 and Sugar all drying varieties. 

 The Robe de Sergeant (supposed 

 to be a synonym of the Prune 

 d'Agen in France) in California 

 is grown as a distinct variety. 

 The fruit is larger, usually more 

 highly flavored, and has com- 

 manded higher prices in the San 

 Francisco market. The tree, 

 however, has not proved so widely 

 adaptable, and is in disfavor on 

 account of defective bearing. The 

 Silver prune (an Oregon seedling 

 of Coe Golden Drop) is also a 

 defective bearer in some districts, 

 and is used mostly in the prep- 

 aration of "bleached prunes," 

 for which it has proved very prof- 

 itable in some instances. It is 

 sometimes marketed in the fresh 

 state also. The Imperial Epineuse, 

 a recently introduced French 

 variety was largely planted but though large, it has 

 proved rather irregular in bearing, difficult to cure and 

 very subject to thrip injury. Luther Burbank's Sugar 

 prune bases its claims upon superior earliness, sweetness 

 and flavor, together with fair medium size. It dries easily 

 but is of coarse texture. The German 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 

 seedling. The fruit of the Hungarian (Pond) is very 

 handsome and showy, and is rated, on its style, a good 

 seller as fresh fruit in both the local and distant mar- 

 kets, but is not suitable for drying. The Tragedy and 

 the Clyman (California seedlings), Giant (Burbank's), 

 Royal Hative, Simon, and Peach, are popular for early 

 market especially for eastern shipment. For canning, 

 Coe Golden Drop and the Imperial Gage are the most 

 popular. The Jefferson, Washington, and Yellow Egg 

 are all highly regarded, and planted more or less widely, 

 as they suit the different climatic regions. Many of 

 the Japanese plums are grown. Red June, Satsuma, 

 Burbank, Wickson, Climax, Santa Rosa, and Formosa 

 (all Bin-bank varieties) are prominent for eastern 

 shipment, local market and domestic use. 



See Wickson's "California Fruits and How to Grow 

 Them," the Reports of the California State Board of 

 Horticulture, and the Reports and Bulletins of the 

 California Experiment Station. 



ARNOLD V. STUBENRAUCH. 



E. J. WlCKSON.f 



PLUM, CHERRY: Prunus cerasifera. P., Cocoa: Chryso- 

 balanus Icaco. P., Date: Diospyros. P., Governor's: Flacourtia 

 Ramontchi. P., Japan: Properly Prunus salicina; improperly 

 applied to the loquat, Eriobotrya japonica. P., Marmalade : Lucuma 

 mammosa. 



PLUMBAGO (from Latin for lead, from the lead- 

 colored flowers of some species, or because of some old 

 tradition). Plumbaginace^e. LEAD WORT. Subshrubs 

 or herbs, often cultivated, particularly under glass, 

 for the handsome phlox-like flowers. 



Mostly perennial, sometimes climbing, often more or 

 less woody: Ivs. usually alternate and entire, clasping 

 (or auricled) by the blade or by base of petiole: fls. 



