GROWTH AND MATURATION OF THE WOOD OF PLANTS. 197 



arities of growth, it will be as well to remark that this wonderful 

 rapidity of elongation is effected almost entirely (in man}- in- 

 stances quite so) without any root action. Upon examination it 

 will be found that the roots are as dormant as at mid-winfer ; 

 but immediately on the completion of the process, and when 

 maturation commences, all the root resources of the tree are put 

 in motion to recruit its exiiausted energies, to afl'ord organizable 

 matter for the perfection of the current season's growth, and to 

 store up matter as a reservoir from which the growtli of the 

 ensuing spring is to derive its substance. Other varieties of 

 growth are presented to us in plants of the " hard-wooded " class ; 

 but unlike the instances just enumerated, the growth is com- 

 paratively slow, and both the processes, elongation and matura- 

 tion, are taking place at the same time and in the same shoot. 

 Pimelea, Erica, Epacris, and genera of a similar cliaracter are 

 familiar examples. Here is no extraordinary rapidity of groMth, 

 no distinction of processes. The base of a shoot half a dozen 

 inches in length will give every character of development from 

 perfect maturity to simple cellular tissue which the pressure of 

 the finger would crush. Here we find a great distinction in the 

 phenomena of elongation. In the Rhododendron all the matter 

 forming the current season's shoot had to be derived directly 

 from the past season's growth. In the Erica the foliage of a 

 shoot of the current summer, of a shoot still growing, is capable 

 of elaborating matter for the elongation of the growing point. 

 Another peculiarity of growth is observable in those numerous 

 plants of quick growth from which we obtain both wood and 

 flower in a comparatively short period, the production of such 

 having only an indirect relation Jis regards beauty or abimdance 

 to the strength or vigour of the plant during the past seai>on of 

 growth. Of this class I may mention Geranium, Justicia, Poin- 

 settia, and all such plants as are pruned back to within a few 

 buds of the old wood, the aim of the cultivator being to pro- 

 duce an entire new growth for the production of foliage and 

 flowers. 



Now it must be obvious to the most cursory observer, that the 

 phenomena of growth, and the organic development of each of 

 the three peculiarities of growtli which I have instanced, must 

 differ widely ; or, in other words, that the constitution of each 

 must bear a totally different relation to the same external circum- 

 stances. Taking the growth of plants in its widest application, 

 three distinct processes are exhibited to us, viz., that of furnishing 

 matter for the current growth ; recruiting the exhausted energies 

 of the plant, and furnishing materials for soliGifjing that growth ; 

 and storing up organizable matter available for a new grow th in 

 the ensuing spring or season of growth. 



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