A treatise on the nature of trees


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Página 42 - Let the head of the tree increase, and, depend upon it, there will be a corresponding increase of the stem. "It is said to be right to cut away a small proportion of the weaker branches, and turn the current of the descending sap more abundantly into the stem. It is hard to understand what is meant by this explanation of the effects of pruning.
Página 35 - The same general laws operate upon the whole kingdom of vegetables ; and thence it is plain that the effects of culture on trees, though different in degree, must be analogous in their nature. * * * "The general effects of pruning I have already stated to be of a corresponding nature with those of culture — that is, to increase the quantity of timber produce. The particular manner in which it does this is by directing the greater part of the sap, which generally spreads itself in side-branches,...
Página 14 - Their development is most luxuriant in ground that is neither too loose nor too dense. In stiff and poor soils, they are spare and scraggy ; whereas, in such as are at once deep and loose, the minutest fibres both expand and elongate with facility...
Página 13 - ... of time. Thus, in an animal, the digestive and the absorbent, the sanguineous, the respiratory, and the nervous systems are at once relative and correlative. In like manner, in a plant, the same reciprocal proportion is found to hold between the roots and the stem, the branches and the leaves : Each modifies and determines the existence of all the others, and is equally affected by all, in its turn.
Página 35 - Knight, and Speechly. No good phytologist will doubt, that it is according to sound science, as well as good practice, in woods planted for profit, and in a soil and climate which are natural to them, or below that standard, to cut away a small proportion of the weaker branches, and turn the current of the descending sap more abundantly into the stems.
Página 20 - ... roots. Secondly, their larger heads, with spreading Branches, in consequence of the free access of light, are formed as plainly for the nourishment, as well as the balancing of so large a Trunk, and also for furnishing a cover, to shield it from the elements. Thirdly, their superior thickness and induration of Bark is, in like manner, bestowed for the protection of the sap vessels, that lie immediately under it, and which, without such defence from cold, could not perform their functions.
Página 27 - It must have branches when but a foot or two high; the number and size of these branches must increase as the tree increases in height, and a tree thirty feet in height, must have a great number of branches; yet we have the stems of trees thirty feet high without a single branch. How do the advocates for pruning reconcile this to their philosophy, will they assert that the stem is stretched or protruded, so that the boughs, first situated near the ground are, by the growth and lengthening of the...
Página 20 - ... considering the characteristics of trees above mentioned, we should always bear in mind, that every production of nature is an end to itself, and that every part of it is, at once, end and mean. Of trees in open exposures we find, that their peculiar properties contribute, in a remarkable manner, to their health and prosperity. In the first place, their shortness and greater girth of stem, in contradistinction to others in the interior of woods, are obviously intended to give to the former greater...
Página 18 - In like manner, in all the other relations, we see Nature especially accommodating the character of each individual plant to the exigencies of its particular situation. In the interior of woods, the wind can exert a far less mechanical effect on individual Trees ; and therefore, while they are positively determined to push upwards towards the light, they are negatively permitted to do so, by the removal of any necessity to thicken their trunks, for the sake of greater strength, and to contract the...
Página 51 - ... For this reason, we see, that every animal, and every plant is dependent for its existence, and also for its perfect existence, on conditions both internal and external. From this reasoning it may be conceived, how the several parts of the living whole reciprocally act and react. They are, in fact, cause and effect mutually ; and no one can precede another, either in the order of nature, or of time.

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