2718 



PLUM 



PLUM 



grown in the cold northwestern states (except the com- 

 paratively unimportant nigras and the Miners) and 

 then- usefulness in northern New England and middle 

 Canada is limited only by the extent to which they 

 are known. Their cultivation has been developed to 

 a special degree in Iowa, Wisconsin, Minnesota, and 

 adjacent states. For this region they must be propagated 

 always on americana stock. This stock has other 

 advantages besides its hardiness, and it is coming into 

 extensive use for all sorts of plums in the Northwest. 

 The sand cherry is sometimes used as a stock, but has 

 not yet passed the experimental stage. It dwarfs 

 americana plums worked on it. It is perfectly hardy. 



The americana plums are wayward and awkward 

 growers. With many varieties it is impossible to make a 

 comely orchard tree. They do not appear to take 

 kindly to pruning; and the usual method has been to let 

 them very much alone. Careful pruning during the first 

 few years, directed with a view to forming an open top 

 on comparatively few supporting main branches, will 

 do something toward shaping the trees; but with our 

 present knowledge, no extensive pruning can be recom- 

 mended for mature trees. The method of heading-in, 

 as often practised with the domestica plums, is espe- 

 cially unadapted to the americanas. 



The americana plums are early and very prolific 

 bearers. Overbearing is a habit and a serious fault 

 with most varieties. Extensive thinning of the fruit 

 is indispensable. The trees are sometimes severely 

 attacked by shot-hole fungus, and thorough spraying 

 with bordeaux mixture or lime-sulfur is necessary. 

 The fruit-rot (sclerotinia) attacks all the native plums 

 more or less, and must be controlled by the usual reme- 

 dies. See Diseases and Insects, Vol. II. 



The nigra group has two or three important varie- 

 ties of superor hardiness, as Cheney and Aitkin. In 

 general, they bloom earlier 

 and fruit less heavily than 

 the americanas. Their 

 habits and culture are the 

 same. 



The Miner-like varie- 

 ties are hardly to be dis- 

 tinguished from the ameri- 

 canas in any way. They 

 have practically the same 

 geographical range, and 

 may be given the same 

 treatment in the orchard. 



The hortulana group 

 includes several varieties 

 of great value, especially 

 for the South. Of these, 

 Wayland, Golden Beauty. 

 Moreman, Benson, ana 

 Kanawha may be men- 

 tioned. They are not to 

 be recommended generally for localities north of Massa- 

 chusetts and Nebraska, their northern limit being deter- 

 mined less by their non-hardiness than by the very late 

 ripening. This habit of late ripening, combined with very 

 late blooming, makes them desirable for late marketing, 

 particularly in southern markets. They are very pro- 

 lific and constant bearers. The trees are free-growing, 

 usually of rather spreading habit, and will bear head- 

 ing-back better than the americanas. The pruning-knif e, 

 if used in season and with good judgment, will assist in 

 making comparatively open-headed trees of these 

 varieties. 



The Wild Goose group (P. Munsoniana) includes 

 varieties like Wild Goose, Milton, Wooton, and Whit- 

 aker, specially adapted to the latitude of Maryland, 

 Kentucky, and Kansas. They succeed only less well 

 southward; but are not generally valuable to the north 

 of this line. For the section named, the varieties of this 

 class have unquestionably been the most profitable 



3073. The Japanese type (Primus salicina). Maru; once grown. 



plums grown up to the present time. They are prop- 

 agated chiefly on peach, Marianna, and Myrobalan, 

 but succeed even better on americana stocks. These 

 stocks are all fairly satisfactory, though not equally 

 good for all varieties; but, when peach stocks are used, 

 the union should be made by whip-grafting on the 

 peach root. Otherwise the peach stock comes above 

 the ground and is a prey to the peach borer. The trees 

 are mostly rapid willowy rather zigzag growers; and 

 are amenable to the pruning-knife in about the same 

 degree as the Wayland-like varieties already mentioned. 

 Whitaker makes an open-headed tree without much 

 trouble. So does Sophie. Wild Goose is more inclined 

 to be thick and thorny in the top, but may be thinned 

 carefully to make an accessible head. Milton is much 

 like Wild Goose. Wooton makes a fine vase-form top, 

 which, with a little timely pruning, is almost ideal. 

 Wilder, James Vick, and some others, are prone to 

 make thick bushy thorny tops, and are hard to manage. 

 These varieties are all considerably subject to shot-hole 

 fungus, which often strips them of their foliage in mid- 

 summer. They are mostly thin-skinned and liable to 

 crack at ripening times, especially if the weather is wet. 

 They should be picked rather green for shipment, the 

 point to be observed being that they have attained their 

 full size, rather than that they are dead ripe. 



The Chickasaw varieties (P. angustifolia) are effec- 

 tive pollinizers for the Wild Goose and Japanese varie- 

 ties blooming at same time; but very few of them have 

 sufficient value in themselves to make them profitable 

 orchard trees. A few varieties, like Munson and 

 McCartney, are still planted for their own fruit; but in 

 general they have been displaced by other types of 

 plums. The trees are mostly bushy, thorny and thick- 

 topped, sometimes so thick and thorny that the black- 

 birds can hardly get in to steal the fruit. It is difficult 

 to prune them enough 

 to make really satisfac- 

 tory trees. The Chicka- 

 saw plums are specially 

 adapted to the southern 

 states, though Pottawat- 

 tamie (probably a form of 

 Prunus Munsoniana) suc- 

 ceeds as far north as 

 southern Iowa and central 

 Vermont. They propagate 

 readily on any kind of 

 stocks, but are very much 

 given to suckering wher- 

 ever they make roots of 

 their own. 



Other types of native 

 plums, such as the Sand 

 plum, the Beach plum, 

 the Pacific plum, and the 

 like, are not sufficiently 

 numerous in cultivation for their treatment to have 

 been determined. 



Hybrid plums of various strains have been intro- 

 duced in considerable numbers. Most of these hybrid 

 varieties resemble rather strongly one or the other of 

 their parent species; and the best that can be said 

 regarding their culture at this early day is that they 

 may be safely treated like the varieties which they most 

 closely resemble. Wickson, President, and perhaps 

 Climax, with some others, resemble the Simon plum, 

 and ought to have much the same treatment, that is, 

 practically the same treatment as the Japanese varie- 

 ties. Gonzales, Excelsior, Golden, and Juicy, on the 

 other hand, resemble the Wild Goose type, and may 

 have the same general treatment as Wild Goose. Some 

 of these hybrid varieties, especially crosses of Wild 

 Goose and Chickasaw types with the Japanese plums, 

 are making some stand commercially, especially in the 

 South, West, and in the Rocky Mountain States. 



