194' 



SCIENCE OF THE STUDY OF TREES. 



PART II. 



face on which the tree grows. The next point is, to observe whether the head 

 is open and airy, or compact ; and the last, whether the general form of the 

 tree is regular or irregular. All these particulars are equally applicable to 

 shrubs as to trees ; with the exception of those which apply to the trunk, 

 which is almost always wanting in what are pictorially, as well as botanically, 

 considered as shrubs or bushes. 



The different points, then, to which attention ought to be directed in the 

 study of trees and shrubs as pictorial forms, are the following : — the height and 

 breadth, or general magnitude, of the tree ; the form and outline ; the colour, 

 light, and shade ; the position of the trunk and branches ; the mode of growth ; 

 the mode of tufting ; the leaves, and the spray and buds.i 



The height and breadth of trees and shrubs vary according to their kinds, and 

 to the soil, situation, and climate in which they grow. The trees of greatest 

 height, in the temperate regions of the globe, are those of the pine and iir tribe ; 

 and they are those, also, which have least breadth in proportion to their height ; 

 because their branches, technically called frondose, have not the same tendency 

 as those of other trees to increase in thickness with the age of , the tree. The 

 most bulky trees, or those which have the greatest width of head in propor-r 

 tion to their height, are some species of poplars, elms, oaks, &c., and the cedar 

 of Lebanon, which, though it is a tree with frondose bi*anches, yet, when it 

 stands singly, has a head generally broader than its height. The highest shrubs, 

 which grow independently of other objects of support, are, among evergreens, 

 the common laurel, and, among deciduous kinds, the common lilac, the dog- 

 woods, and the Guelder rose. Among the smallest trees, considered as picr 

 torial objects, are the thorns and the spindle tree; and among the smallest 

 shrubs are the heath, the furze, and some of the rhododendrons and azaleas. 



The form and oidlhie of trees and shrubs vary chiefly according to their kinds 

 and their age, but partly, also, according to the physical circumstances in 

 which they are placed ; such as soil, situation, climate, and, perhaps, above all, 

 proximity to other trees and shrubs. The natural form and outline of a tree can 

 only be ascertained when the tree stands alone. The form which it assumes, when 

 closely surrounded by other objects, will generally be found very different from 

 its natural form ; and, therefore, cannot be considered as characteristic of the 

 tree or shrub. Even the climate, or the prevailing soil or wind, will materially 

 alter the form. The cedar, when planted in masses like the larch or the Scotch 

 pine, produces, like them, a straight trunk, with the branches dying off from 

 the bottom upwards; planted singly, its branches often become like so many 

 trunks : in a sheltered situation its top will be pointed ; and, in one exposed, 

 it will become blunt or flattened, like the well-known cedars of the Chelsea 

 Botanic Garden. Nearly the same observations may be made respecting all 

 other trees : even the sturdy oak, in poor soils and cold elevated situations, 

 becomes a bush ; in rich soils and low situations it is a lofty tree, with a straight 

 trunk ; and in situations exposed to the sea breeze, it has the entire head of 

 the tree leaning to one side, and presents an appearance altogether peculiar. 

 Fig. 1. shows the effect of the sea breeze on two oaks growing on the boundai-y 

 of Canford Heath, near Wimbnrne, in Dorsetshire ; and numerous similar 

 examples might be given from different parts of the island. 



However various the outline of trees and shrubs may appear in detail, the 

 general contour may always be reduced to some familiar or recognised form, 

 easily retained in the memory: for example, to that of an oval, or that of an 

 egg placed on its smallest end, which are the most conmion forms of trees, 

 except in the case of those which have frondose branches ; and that of an 

 egg placed on its broadest end, or of a flattened cone, which are the most com- 

 mon forms of shrubs. The Lombardy poplar, the cypress, and some similar 

 trees, may be said to have their heads in the form of an ellipsis : and others, 

 such as the common apple, thorn, &c., in that of a globe, or in that of a semi- 

 globe. A few trees, more particularly in their young state, take the form of an 

 inverted cone, such as the planera, as will apjjear hy our figure of that tree at 

 ten years' growth. Within these general forms, the greatest variety of outline 



