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THE planter's GUIDE. 



a remarkable raaniier, 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 

 strength to resist the winds, and a shorter lever to act 

 upon the roots. Secondly, their larger heads, with 

 spreading branches, in consequence of the free access of 

 light, are plainly formed for the nourishment, as well 

 as the balancing of so large a trunk, and also for furnish- 

 ing 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. 

 Fourthly, their greater number and variety of roots are 

 for the double purpose of nourishment and strength ; 

 nourishment to support a mass of such magnitude, and 

 strength to contend with the fury of the blast. Such are 

 the obvious purposes for which these unvarying charac- 

 teristics of trees, in open exposures, are conferred upon 

 them. Nor are they conferred equally and indiscrimi- 

 nately on all trees so situated. They seem, by the 

 economy of nature, to be peculiar adaptations to the 

 circumstances and wants of each individual, uniformly 

 bestowed in the ratio of exposure — greater where that is 

 more conspicuous, and uniformly decreasing as it becomes 

 less. 



On the other hand, in the interior of woods a universal 

 tendency, for the reasons already stated, is observable in 

 trees to rise to the light, to attain greater altitude, to 

 form far smaller heads, and taller, slenderer, and more 

 elegant stems. Here is found a milder and more genial 

 climate, in which, by means of the calm generated by 

 shelter, vegetation is not checked by cold, and at the same 



