April io, 1889.] 



Garden and Forest. 



177 



Too Few Varieties. — It is good counsel that advises growers 

 to set but few varieties, but the advice and practice may be 

 carried too far. Tlie number and kind of varieties must de- 

 pend upon conditions, largely conditions of market. It is not 

 good practice to set a variety simply because every one else 

 does. Markets often demand a variety of products. Tastes 

 change. Many apple-growers in western New York would 

 have been glad of something besides Baldwins last fall. 

 Plan a succession. Plan for various available markets, and a 

 variety of ways of disposing of the crop. This usually de- 

 mands more than one or two varieties. L. H. Bailey. 



Cornell University. 



Notes from the Arnold Arboretum. 



THE season here is a very early one, at least twelve or fif- 

 teen days earlier than the average, and fully twenty days 

 earlier than that of last year. There is hardly any frost in the 

 ground, except in deeply-shaded situations, although it is un- 

 usually full of water. Broad-leaved evergreens and conifers, 

 without exception, look unusually fresh and well ; of decid- 

 uous plants it is still too early to speak with much confidence, 

 as they rarely show the ravages of winter, until it is time for 

 the leaf-buds to begin to swell. 



The eariiest shrub in flower (it has been in bloom for fully 

 two weeks, and is still fresh) is the Japanese Witch Hazel 

 [Hatnamelis Japonicd). As it now appears, covered with its 

 bright canary-colored flowers, it is a cheerful and pleasing 

 object, which may well find a place near the window of every 

 northern home for this early cheerfulness, which does not 

 succunib to hard freezing or to the inevitable spring snow- 

 storm of New England. The Japanese species is very closely 

 allied to our familiar American Witch Hazel, although the 

 leaves are somewhat narrower, more inclined to be slightly 

 lobed, of rather different texture and of a duller green. The 

 flowers are produced in very early spring, instead of in late 

 autumn, and the petals are narrower and perhaps brighter 

 colored. In the flower on the Arboretum plant the calyx is yel- 

 low; but that it is sometimes purple or red appears from the 

 figure of this species (/. 6,659) published in a recent volume of 

 i!a.Q Botanical Magazine. But this evidently is not a constant 

 character, and was not considered by Franchet Sr' Savatier,\\rho 

 discussed the differences between this and the American 

 species {Enum. pi. Jap. ii., 368). They found the best dis- 

 tinction in the number of the principal veins of the leaf ; a char- 

 acter which does not, however, at all hold in our cultivated 

 plants. The time of flowering very well separates the two 

 species, however, for any garden purpose, at least ; while the 

 differences in habit and in the general appearance of the leaves 

 are equally well defined and constant. Hamamelis Japonica 

 becomes in its native country a small tree. It was introduced 

 into Europe and thence to the United States by the Veitches. 

 A third species (//". mollis, Hooker's Icones Plafttarimi, 1. 1741) 

 is one of the new discoveries in central China. 



Erica carnea is beautifully in bloom, and so are the native 

 and some of the foreign Alders. These were closely followed 

 by several foreign species and varieties of Hazel, most of 

 which bloom ten or fifteen days earlier than our native spe- 

 cies. The two earliest (probably merely forms of the same 

 species) are two north China and Manchurian plants, culti- 

 vated here under the name of Corylus Manchurica and C. 

 heterophylla. They form neat, compact bushes, three feet 

 high, with ashy-gray branches and handsome foliage, which 

 turns brilliantly in the autumn. They now bear male and fe- 

 male flowers abimdantly, so that there is a prospect for fruit, 

 which has not yet been produced here. These are plants to 

 be better known and more often seen in gardens, although, of 

 course, they will never be favorites with people who only 

 value shrubs for their showy flowers. 



It is interesting, now that the winter is over, to look through 

 the collection and see what plants have retained their fruit 

 bright and fresh up to this time, and which are, therefore, the 

 most desirable for the winter decoration of shrubberies. The 

 list is not a very long one ; six weeks ago it could easily have 

 been made much longer, for it is the rains and the warm suns of 

 February and March which cause the fruits of many plants to 

 become discolored from decay. The fruit of Berberis Thun- 

 bergii is perhaps in the best condition of any in the collection. 

 It is as bright and nearly as abundant as it was in November, 

 and has not shrivelled perceptibly. The fruit has disappeared 

 almost entirely from all the other species of Berberis. The 

 scarlet fruit of Vihiirniun Opuliis (the Cranberry-tree) is still 

 hanging on the plants in considerable profusion, not having 

 been devoured this year by birds, as is generally the case. 

 The fruit shows the effects of hard freezing, but is almost as 



bright in color as it was in the autumn. And this is true of the 

 fruit of the Black Alder i^Ilex verticillata), which birds do not 

 seem to relish and which is still very abundant and fresh, 

 making the plants conspicuous and beautiful objects. Many 

 Roses a month ago were still covered with brilliant-colored 

 hips, but these have now turned black on nearly all the spe- 

 cies, native as well as foreign. The most conspicuous excep- 

 tion, however, is our common Swamp Rose {Rosa Caroliniana), 

 which is loaded still with highly-colored fruit, and Rosa repens, 

 with its slender, pear-shaped maroon hips. The fruit of 

 Rosa nitida is still presentable, although less so than that of 

 either of the species just named. Scarlet and red fruits seem 

 to keep better, on the whole, than black ones (although, no 

 doubt, the coincidence is quite accidental), but the exception 

 is Ligustrum vulgare, whose jet black berries are as abundant 

 and deeply colored now as at any time during the year. 

 Birds, apparently, have nothing to do with them. The black 

 fruit of Cornus sajtguinea is still abundant upon the plants and 

 fairly well colored, although losing fast its freshness. Of other 

 black fruits there is hardly a trace left in the collection. 



Among plants here which are conspicuous in winter on 

 account of the highly colored bark covering their stems and 

 branches, by far the handsomest and most desirable in every 

 way is that variety of Cornus alba, sometimes known in nur- 

 series of C. Sibirica. It is evidently a variety of the widely- 

 distributed C. alba, but what its origin or history is I have 

 not been able to discover. The bark is bright I'ed, much 

 brighter than that of C. alba, or of anyother species of Cornus — 

 a genus which furnishes some of the brightest objects which 

 can be used for the decoration of winter gardens or shrub- 

 beries. 



March 29th. J • 



Principles of Physiological Botany, as Applied to 



Horticulture and Forestry, 



XV. — Seed-breeding. 



A S we have already seen, a plant, for instance an Elm, is a 

 ■^~*- community of individuals, and it possesses such a degree 

 of unity between all the component parts, that in popular lan- 

 guage we speak of it as an individual. This term "individ- 

 ual " can be used also in scientific language with convenience, 

 and hence it is frequently customary to speak of a given elm, 

 rose or phlox as an individual. When, now, we compare all 

 the elms with all the roses and all the phloxes, we see at once 

 that we are dealing with widely-separated kinds of individuals. 

 These kinds are known as genera. 



If, next, we restrict our observation to all the elms we know, 

 we are struck at once by the existence of certain differences 

 which render it necessary for us to divide the genus elm into 

 minor groups, such as the Slippery-elm, the American Elm, 

 the Enghsh Elm and the like. In the same manner we class- 

 ify the roses into such groups as the Sweet-brier, the Dog-rose, 

 the Prairie-rose, and so on. The phlox genus readily breaks 

 up into such groups as Drummond Phlox, Panicled Phlox, 

 Spotted Phlox, etc. These minor groups, into which the genus 

 is divided, are known as species. 



But these species comprise innumerable individuals which 

 differ from each other in some particulars. For example, 

 Drummond's Phlox is a species containing countless forms 

 which differ from each other in the matters of color, height 

 and smoothness. These divergent forms within the limits of 

 the species are known as varieties. 



It was formerly hekl by botanists that between varieties and 

 species there exist absolute distinctions, but, of late years, the 

 view has been gaining ground that species and varieties may 

 grade into another. Between certain species there are numer- 

 ous intermediate forms which conceal any line of demarca- 

 tion. There are wide differences between the degrees of 

 likeness and unlikeness presented by varieties; some varieties 

 are almost like the general average of the forms whicli make 

 up the species, while others are very different indeed. 



There is another very marked difference between certain 

 varieties : some of them can be perpetuated by seeds, while 

 others cannot. The latter vary from the parent plant in many 

 particulars, while the former come, as we say, " true to seed." 

 Varieties which come true, or reasonably true, to seed are 

 termed races. If, therefore, we have a choice race of plants, we 

 can, with a fair degree of success, propagate it by means of 

 seeds, and year after year we shall have substantially the same 

 results. If, however, our choice form of plant is only a mere 

 variety, we are compelled to propagate it by means of cuttings 

 or by the transfer of buds in some way. In this manner we 

 perpetuate desirable varieties of apples, pears and roses : by 

 grafting or budding, by layering or by cuttings, as experience 



