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THE PLUM 



DOMESTICA PLUMS 



hardier than that of the peach. There are no 

 named varieties. 



THE PLUM 



Cultivated varieties of thirteen species of 

 plums are found in American orchards. The 

 names and relationships of these species are 

 shown in the following conspectus. 



CONSPECTUS OF SPECIES OF PLUMS 



A. Flowers in clusters of 1 or 2. (Three in P. salicina.) 



Old World plums. 

 B. Leaves drooping. 

 C. Shoots and pedicels pubescent. 

 D. Flowers mostly in twos. 

 E. Fruit large, more than I inch in diameter, 



variable in shape 1. P. domestica. 



E.E. Fruits small, less than 1 inch in diameter, 



oval or ovoid 2. P. insititia. 



C.C. Shoots glabrous or soon becoming so, pedicels 



glabrous. 

 D. Flowers single ; leaves hairy along the midrib on 



the under side 3. P. cerasifera. 



D.D. Flowers in threes ; leaves glabrous. 



4. P. salicina. 



B.B. Leaves upright, peach-like, glabrous, veins very 

 conspicuous, under side barbate at axils of veins ; 

 separated from other plums by the large, flattened, 



brick-red fruits 5. P. Simonii. 



A.A. Flowers in clusters of 3 or more. American plums. 

 B. Plants trees. (P. angustifolia rarely a tree.) 



0. Leaves broad, mostly ovate or obovate. 

 D. Leaves long-ovate or long-obovate. 



E. Flowers white. 



F. Leaf-serrations glandless, acute ; petiole usually 

 glandless ; stone turgid, large, pointed at the 



apex 6. P. americana. 



F.F. Leaf -serrations, glandular, wavy-crenate ; peti- 

 oles glandular ; stone turgid, small, prolonged 



at the ends 1. P. hortulana. 



E.E. Flowers fading to pink. Leaf-serrations coarse, 

 rounded, glandular only when young ; petioles 

 bi-glandular ; stone flat, large. 



8. P. nigra. 

 D.D. Leaves round-ovate, obtusely, sometimes doubly 



serrate ; stone turgid, pointed at both ends. 



9. P. subcordata. 

 C.C. Leaves narrow, Lanceolate-ovate, folded upward. 



D. Fruits small, % inch in diameter, cherry-like ; 

 petiole bi-glandular ; stone small, ovoid, turgid, 

 cherry-like ; rarely a tree ; tender. 



10. P. angustifolia. 



D.D. Fruits large, 1 inch in diameter, plum-like ; 

 petioles with from 1 to 6 glands ; stone com- 

 pressed and pointed at both ends ; usually a 



tree ; hardy 11. P. Munsoniana. 



B.B. Plants shrubs. 



C. Fruits dark purple ; stones pointed at both ends. 



12. P. maritima. 



C.C. Fruits red, orange or yellow but never purple ; 

 stone oval, flattened 13. P. orthosepala. 



Domestica Plums 



1. Prunus domestica, Linn. Tree vigorous, open- 

 headed, round-topped ; trunk attaining 1 foot or more 

 in diameter ; bark thick, ashy-gray with a tinge of red, 

 nearly smooth or roughened with transverse lines. Leaves 

 large, obovate, elliptical, thick and firm in texture ; 

 upper surface dull green, rugose, glabrous or nearly so, 

 the lower one paler with little or much tomentum, much 

 reticulated ; margins coarsely and irregularly crenate 

 or serrate, often doubly so ; teeth usually glandular ; 

 petioles % inch in length, stout, pubescent, tinged with 

 red ; glands usually 2, often lacking, sometimes several, 

 globose, greenish-yellow. Flowers appearing after or 

 with the leaves, showy, 1 inch or more across, white ; 

 borne on lateral spurs or sometimes from lateral buds 

 on one-year-old wood, 1 or 2 from a bud in a more 

 or less fascicled umbel ; pedicels % inch or more in 

 length, stout, green. Fruit globular or sulcate, often 

 necked, blue, red or yellow ; stem % inch or more 

 long, stout, pubescent ; cavity shallow and narrow ; apex 

 variable, usually rounded ; suture prominent, a line or 

 indistinct ; dots small, numerous, inconspicuous ; flesh 



yellowish, firm, sweet or acid and of many flavors ; stone 

 free or clinging, oval, flattened, blunt, pointed or 

 necked, roughened or pitted ; walls thick ; one suture 

 ridged, the other grooved. 



This is the plum in which fruit-growers are 

 chiefly interested. The Domestica plums not 

 only are the best known of the cultivated 

 plums, having been cultivated longest and 

 being most widely distributed, but also far 

 surpass all other species, both in the quality 

 of the product and in the characters which 

 make a tree a desirable orchard plant. Al- 

 though records are vague, it is probable that 

 the Domestica plums came from the region 

 about the Caucasus Mountains and the Cas- 

 pian Sea. What seems to be the wild form 

 of this species has been found by several 

 botanists in this great region. Here the Huns, 

 Turks, Mongols, and Tartars, flowing back 

 and forth in tides of war-like migration, main- 

 tained in times of peace a crude agriculture 

 long before the Greeks and Romans tilled the 

 soil. The plum was one of their fruits and 

 the dried prune a staple product. Here, still, 

 to the east, west, and north toward central 

 Asia, plums are among the common fruits, 

 and prunes are common articles of trade. 

 Even in the fertile oases of the great central 

 Asian desert, plums are cultivated, but whether 

 domesticated here or brought from elsewhere 

 is unknown. At about the time of Christ, or 

 somewhat before, communication had been 

 opened between the Romans and the countries 

 about the Caspian Sea, and a few centuries 

 later hordes of Asiatics came westward and 

 for several centuries continued to pour into 

 eastern Europe. What more probable than 

 that they should have carried dried prunes as 

 an article of food in the invasions, and eventu- 

 ally, as they made settlements here and there, 

 have introduced the trees in Europe? It is 

 certain, at any rate, that several of the groups 

 of cultivated plums trace back to the Balkan 

 countries of Europe and the region eastward. 



The Domestica plums are valuable food- 

 producing trees in America, but have not at- 

 tained the relative importance among fruits 

 that they hold in Europe. From the earliest 

 records of fruit-growing in the New World, 

 the plum has been grown less than the apple, 

 pear, peach, or cherry, while in Europe it is a 

 question if it does not rank first or second 

 among the tree-fruits. The comparatively re- 

 stricted area which the Domestica plums now 

 occupy in America is due to the fact that they 

 do not possess in so high degree as the fruits 

 named the power of adaptation to the trans- 

 Atlantic environment. Without question, the 

 feature of environment most uncongenial to 

 plums in America is the climate. The plum 

 thrives best in an equable climate like that 

 of eastern and southern Europe and of western 

 America, and cannot endure such extremes of 

 heat and cold, wet and dry, as are found in 

 parts of eastern America and in the Mississippi 

 Valley. This fruit lacks ability to withstand 

 adverse conditions of any kind, whether of 

 climate, culture, insects, or fungi. Thus, in 

 America, this plum suffers severely, not only 



