PRUNING 



PRUNUS 



1445 



The rapidity with which wounds heal depends very 

 largely on their position on the tree and the way in 

 ■which they are made. Wounds along the main 

 branches, which are the leading avenues for distribu- 

 tion of food, heal more speedily than those on the 

 \reaker side branches. The closer the wound sits to the 

 branch, the more quickly 

 will it heal. Fig. 1973. If a 

 stub is left several inches 

 long (Fig. 1975), it seldom 



therefore, where they make great display, but their short 

 season of bloom and the very ordinary foliage of most 

 of them have limited the planting of the ornamental 

 kinds. Some of the ornamental species are not grown 

 on their own stocks, but are worked on stocks that can 

 be grown easily and cheaply and of which seeds can be 

 obtained in abundance. The commonest stocks for the 

 ornamental kinds are the plum (P. domesfica), peach 

 and sweet cherry. On the plum are grown the dwarf 

 almonds and the double-flowering and fancy-foliage 



1972. The healing tissue 

 arises from the side of 

 the wound, not from 

 the hard wood. 



1973. A well-covered 

 wound. 



The pruning was prop- 

 erly done, no stub being 

 left. 



heals until it rots back to the main branch or trunk; and 

 by that time the decayed heart may have extended deep 

 into the tissue of the tree. It is a common notion that 

 a limb should be cut at right angles to the direction of 

 the limb itself and beyond the bulge at its base. It is a 

 better plan, however, to make the wound parallel to the 

 ■direction of the branch or trunk that remains, and close 

 to it. This wound may have a somewhat larger super- 

 ficial area, but it is much nearer the source of the heal- 

 ing food supply and therefore becomes covered more 

 ■quickly. L. H. B. 



PRONTJS (ancient Latin name of plum). Rosdcece. 

 Plum, Cherry, Peach, Apricot, Almond, etc. About 

 75 species of pink-flowered or white-flowered shrubs and 

 small trees of wide distribution, but most abundant in 

 the north temperate zone. Lvs. alternate, simple, usu- 

 ally serrate: fls. mostly in spring, sometimes preceding 

 the leaves, either solitary or in clusters, perfect, the 

 pistil single, the stamens numerous and perigynous, the 

 petals and calyx-lobes 5: fr. a drupe, usually 1-seeded 

 by the abortion of one of the two ovules. Fig. 1976. The 

 genus as here outlined includes several well-marked 

 groups, some of which are regarded as distinct genera 

 by many authors. In their extreme or typical forms, 

 these subgenera are very distinct, but there are so many 

 intergradient forms that it seems unwise to keep them 

 distinct as genera. The tendency of plant-breeding is 

 to still further obliterate the differences by means of 

 hybridization. At best, the genus is polymorphous, 

 but the general experience is that confusion is increased 

 rather than decreased by the effort to make two or more 

 genera from it. Many of the forms that appear to be 

 very distinct in their extremes, connect by insensible 

 gradations in intermediate ranges. The dominant East 

 American species, for example, shade off into marked 

 forms in the West and Southwest (see Waugh, 12th Rep. 

 Vt. Exp. Sta., p. 231-239). 



Horticulturally, Prunus is one of the most important of 

 all genera. It includes the stone-fruits, — peaches, plums, 

 cherries, apricots, almonds. It is also prolific of orna- 

 mental subjects, as double-flowered, variegated-leaved, 

 colored-leaved and weeping forms. Most of the culti- 

 vated species are hardy in the latitude of Philadelphia 

 and many are hardy in Ontario. All are of easy culture. 

 Nearly all the species are spring-flowering. Only P. 

 acida, amongst the cultivated kinds, blooms as late as 

 midsummer. They are very useful for spring gardens, 



1974. The stub is longer 

 than necessary, although 

 the fault is not a flagrant 

 one. 



1975- Common fault in pruning 

 This wound cannot heal un- 

 til the stub rots away, and by 

 that time the tree may be 

 irreparably diseased. 



plums. The myrobalan plum (P. cerasifera) is some- 

 times used for the same purpose. Peach stocks may be 

 used for the same species, as a rule; and they are also 

 employed, particularly in the South, for many fruit= 

 bearing plums. The sweet cherry (P. Avium) is a good 

 stock for the various kinds of double-flowered, weeping 

 and fancy-leaved cherries. It is an important point in 

 the growing of these grafted Prunuses to remove all 

 sprouts from the stock as soon as they appear. This is 

 particularly true of the dwarf almonds, since the stocks 

 are usually stronger-growing species and tend to sucker 

 from the root. It is a question whether it would not be 

 better to propagate these dwarf species from layers or 

 cuttings in case seedlings of their own species cannot 

 be had. Own-rooted plants can be secured by root- 

 grafting with a long cion (see Fig. 943, Vol. I). 



In North America there has been a most remarkable 

 contemporaneous evolution of fruit-bearing plums from 

 the native species. Several hundred orchard varieties 

 have been described, and the trees are grown commer- 

 cially over a wide range of country in the South, in the 

 Mississippi valley and on the Plains, — in regions in 

 which the common Prunus domestica does not thrive. 

 Systematic knowledge of these domesticated native 

 plums dates from 1892 (Bull. 62, Cornell Exp. Sta.). 



1976. Flowers of plum. Natural size. 

 The ovary, or young plum, with the ovule inside, is at o. 



For the latest knowledge of the subject, the reader 

 should consult experiment station literature, particularly 

 the writings of Waugh and Goff . See, also, " Evolution 

 of our Native Fruits." 



For fuller information on the fruit-bearing members 

 of the genus, see A Imond, Apricot, Cherry, Nectarine, 

 Peach, Plum, Prune. 



