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crowding it, or impeding its growth by shading or interfering with its foliage. Those 

 which simply shade the trunk or the ground around it are serving a useful purpose, and 

 should not be distui'bed. Indeed, if it is found that the necessary removals involve much 

 increased exposure of the surface soil around the tree, it should at once be covered with 

 a mulching of sufficient depth to prevent the possibility of its becoming heated and dry. 

 All other sources of danger to the health of the trees are insignificant in comparison 

 with that of the rude check they are liable to receive from sudden exposure of the trunks 

 and surface roots to the influence of the sun and wind, from which they have heretofore 

 been protected, and to which they can only become accustomed by a gradual change. 



The next year it will be found that the tree has gladly availed itself of the oppor- 

 tunity for expansion, and has spread its limbs to fill the vacant space around it, so that 

 more trees must now be removed, while the increased mass of foliage it has developed 

 renders it less liable to suffer injury from their loss. 



The removal of the undergrowth of shrubbery, should be very cautiously conducted, 

 and in no case should it be removed from the outskirts of the wood, which should every- 

 where be left with as dense a. growth as possible, to prevent the entrance of the winds. 



The sirocco-like wind from the S. W., which often blows with great violence for 

 days together, especially in the spring and early summer, when the trees are full of sap, 

 and the young shoots and leaves are tender and sensitive, is the one from which most 

 danger is to be apprehended. The merely mechanical injury it inflicts upon the spray 

 and foliage is often serious, but its worst effects are due to its absorption of moisture and 

 vitality. 



All experienced nurserymen and fruit-growers, have learned to dread its exhaust- 

 ing influences especially upon grape vines and other broad leaved plants, and they too 

 are aware of the fact, which comparatively few ordinary observers seem to have noticed, 

 that its effect in giving a general trend of the spray and branches of trees in exposed 

 situations toward the N. E., is so marked that no one who has learned to observe it, need 

 ever be long at a loss to know the points of the compass in any parts of the country. 



The fact, however, that we have it in our power to guard against the evil effects of 

 this wind by artificial means, is not so generally known as it should be, and it was only 

 after many years observation and experience that I came to a full idealization of certain 

 facts in connection with its action, which have a most important bearing upon the ques- 

 tion of forest culture. 



1 became aware, many years since, that many shrubs, trees and plants would grow and 

 thrive at iN'ewport, R. I., and at Yarmouth, Nova Scotia, which in the interior were only 

 found much farther south, and would certainly perish if removed to the latitude of those 

 towns. The reason assigned in both cases was the warming influence of the neighbouring 

 gulf stream, which seemed a plausible explanation in which my faith remained unshaken 

 for years, until I went to Chicago, where I found it was impossible to grow many of the 

 finer fruits, and some of the forest trees which elsewhere are found in much higher lati- 

 tudes. Neither peaches or grapes can be grown at Chicago, or at any other point on the 

 western side of the lake without artificial protection, and the native growth of wood is 

 very meagre, and many varieties which elsewhere are found much farther north, as the 

 beech and the hemlock cannot be grown ; yet the eastern shore of the lake, only sixty miles 

 distant, has no superior in the whole country as a fruit growing region. Peaches, grapes, 

 strawberries, etc., grow most luxuriantly anywhere on that shore up to the northern 

 extremity of the lake, three hundred miles north of Chicago, and every variety of forest 

 tree indigenous to the country is found in the best condition of vigorous health. 



There is no gulf stream to account for this difference, but the relative position 

 towards the lake of the whole extent of its fruitful shore is the same as that of Newport 

 and Nova Scotia towards the ocean. In both cases the S. W. wind reaches the shore 

 after passing for a long distance over water, and instead of burning and exhausting vege- 

 tation with a breath of fire, it comes laden with the moisture it has gathered up in its 

 passage, and brings health and strength upon its wings, instead of disease and death. 

 Further reflection served to convince me that the rule was susceptible of much wider 

 application, and serves to explain the different vegetation of the eastern and western 

 shores of great continents in the same parallels of latitude. Central Spain and southern 



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