1374 



PLUM 



PLUM 



time. Reine Claude, Germau Prune, Copper, are prob- 

 ably best when top-worked on some strong stock. For 

 man)' native varieties, seedlings of vigorous natives, as 

 of Golden Beauty and Wayland, make excellent stocks. 

 Americanas should be worked on their own seedlings, 

 at least in the North. In the South they are often 

 budded on Marianna. 



Plum trees are usually planted when two years old 

 from the bud, although some of the strong-growing 

 kinds may be planted at a year old with the very best 

 results. As a rule. Plum trees are planted about as far 

 apart as peaches are, that is, from 15 to 20 feet apart 

 each way. Many growers prefer to plant them closer one 

 way than the other and eventually to stop cultivation in 

 one direction. If this sj^stem is used, they may be placed 

 18 or 20 feet apart one way, and from 8 to 12 feet the 

 other way. When planted, the trees are pruned in essen- 

 tially the same way that apple trees are. It is generally 

 advisable to start tops as low as possible and yet allow 

 of the workiuic of the curculio catcher below them. This 

 means that the limbs should start from 3 to 4 feet above 

 the ground. With the modern implements and methods 

 of tillage, there is little inconvenience in working the land 

 if tops are started as low as this. The sulisc(juent prun- 

 ing of tlie Plum tree has no special diliiiiilties. About 

 four or five main limbs are allowed to form the frame- 

 work of the top, and in most varieties, especially those 

 which are not very tall growers, the central trunk or 

 leader may be allowed to remain. The frtiit of the 

 Domestlcas is borne mostly on spurs, as shown in Fig. 

 1858. These spurs, therefore, should not be removed 

 unless it is desired to thin the fruit. In the Americanas 

 and the Japanese varieties, the fruit is borne both on 

 spurs and on the annual axial growth. 



Insects and Diseases. — The black-knot is one of the 

 most serious Plum diseases. It is best kept in check by 

 systematically cutting it out. The grower should go 

 over his orchard for it in the summer time and again as 

 soon as the leaves fall. If trees are thoroughly sprayed 

 every year with Bordeaux mixture for the leaf -blight 

 fungus, the black-knot will make comparatively little 

 headway in the orchard. 



The l)light, which causes the leaves to fall in August 

 or September, is one of the most serious diseases in 

 the Plum orchard ; but the disease can readily be kept 

 in check by thorough spraying with Bordeaux mixture 

 two or three times during the summer. The mixture for 

 spraying Plums should be weaker than for apples, par- 

 ticularly for the Japanese varieties. 



The fruit-rot is the work of a fungtis. Many times 

 the dead and dried fruit may be seen hanging on the 

 tree all winter, as shown in Fig. 1859; and in such cases 

 it is very likely that the fruit-spur may be killed, as the 

 upper one in the picture has been. In handling this 

 disease, the first consideration is the fact that some 



1853. Early Red, one of the Russian Plums (X %). 



varieties are much more susceptible to it than others. 

 The Lombard is one of the worst. Again, if the fruit 

 grows in dense clusters, the disease is more likely to be 

 severe. The thinning of the fruit, tlierefore, is one of 

 the very best preventives of the spread of the disease, 

 and at the same time, also, one of the raost efficient 

 means of increasing the size, quality and salableness of 



the product. Thorough spraying with Bordeaux mix- 

 ture is a specific for the trouble. 



The curculio, which causes wormy fruit, can be held 

 in check by the jarring process, as described under 

 Peaclfi. 



For literature on Plums, see Waugh's "Plums and 

 Plum Culture ; " Bulletins by Waugh, Goff and Craig, 

 chiefly on Native Plums. Bull. 131. Cornell Exp. Sta. 



1854. Moldavka, a Russian Plum (X %). 



(from which the above account is adapted); bulletins 

 of Cornell Exp. Sta. on Japanese Plums, and also No. 

 38 on Native Plums. l_ jj b_ 



Cultivation of Native Plums.— Approximately 300 

 varieties of Plums, derived chiefly from 6 native types, 

 are now propagated by American nurserymen and 

 planted in American orchards. A large number of 

 these varieties are comparatively worthless, and must 

 presently be discarded. A creditable minority, however, 

 has qualities of absolute and considerable merit, and 

 may be looked on as permanent additions to our pomo- 

 logical wealth. The native varieties are now propagated 

 and planted bj^ thousands annually, both for home use 

 and for market. For certain culinary purposes many of 

 the natives are superior; and in many places, particu- 

 larly in states of middle latitude, they are the most 

 profitable market Plums grown. 



The Americana Plums are especially qualified to with- 

 stand the severity of northern winters. They are su- 

 perlatively hardy. They are practically the only Plums 

 grown in tlie cold northwestern states (except the com- 

 paratively unimportant Nigras and the Miners) and their 

 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 har- 

 diness, and it is rapidly 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 

 very kindly to pruning; and the usual method has been 

 to let them very nuieh alone. Careful pruning dur- 

 ing 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 recommended for mature trees. The method 

 of heading-in, as often practiced with the Domestica 

 Plums, is especially unadapted to tlie 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 in- 

 dispensable. The trees are sometimes severely attacked 

 by shot-hole fungus, and thorough sjjrayiiig with Bor- 

 deaux mixture is necessjiry. The fruit-rot (nionilia) at- 

 tacks all the native Plums more or less, and must be 

 controlled by Bordeaux mixture. See Spra ii'ntg. 



The Nigra grou]) lias two or three important varie- 

 ties of su])('rior hardiness, as Cliciiev and Aitkin. In 

 general they bloom earlier, aixi fruit less heavily than 

 the Americanas. Their habits and culture are the same. 



