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down on the declivity is directly in front of it. This rising of the tree tops 

 in tiers can often be perceived in forested level costal regions. Only, here 

 the terracing of the tree tops is not produced by inequalities of the soil and 

 trunks equally tall, but by a different height of the trunks, on level soil. It 

 is noticed that where coast winds strike the trees, the outer trees do not 

 grow tall, but are kept down like shrubs. Only at some distance behind 

 these, and increasing with the distance, do they grow to the height of forest 

 trees. Whirlwinds will overthrow whole groups of trees in the centre of 

 an uniform tract. A different natural form of wind protection is men- 

 tioned by Schiibeler^ (see p. 253) for spruce families, from the Gudbrands- 

 dai, at an elevation above sea-level where the spruces approach their height 

 limit. The trees are usually arranged in rows in exposed places, and in fact 

 in such a way that the main trunk stands at the side turned toward the pre- 

 vailing wind, while the branch suckers form a pretty straight line behind ihe 

 parent tree. Therefore, only where this parent tree keeps off the wind is it 

 possible for the young sucker trees to grow up. 



In the tropics the cultivation of cocoa is often affected by the wind 

 storms. Aside from the indirect losses from overthrow^n shading trees, the 

 wind also directly tears apart the forkings of the main branches. Accord- 

 ing to L. Kindt's reports, an attempt has been made to produce tall tree 

 trunks from the remains of the bush forms, injured by the wind, by letting 

 one of the many water sprouts grow up and then forcing it, by topping, to 

 form branches. This process has been found partially advantageous, but 

 has been entirely abandoned by Kindt upon his own experience. He found 

 that in such an artificial formation of the trunks, contrary to the nature of 

 the tree, only scanty, weakly leaved crowns formed of short horizontal 

 branches are produced in which fruits, ripening prematurely, are found only 

 on the trunks. The yield is not satisfactory quantitatively and ciualitatively, 

 not only in the first year, but also in subsequent years. 



The duration and time of the storm, as well as the prevailing weather, 

 should be taken into consideration. In rainy periods, the softened soil 

 gives way more easily and predisposes toward the uprooting of trees by 

 wind (see Sewage Fields), while a spring storm on frozen soil finds the 

 trees more firmly anchored and, w^ith increasing strength, causes more 

 windbreaks. 



Aside from these gross injuries occurring at once, however, those 

 should also be recorded which do not destroy the existence of the individual 

 but only weaken it temporarily or permanently. 



Among wind damages belongs an inclined position of the trunks. The 

 most striking and frequent phenomena are offered by street trees, especially 

 where gutters run along both sides of the avenue or highway. The striking 

 discovery may be made here, that if the street runs perpendicularly to the 

 prevailing direction of the wind (with us usually a west wind), the most 

 exposed rows of trees have comparatively erect trunks, while those on the 



1 Schiibeler, Die Pflanzenwelt Norwegens. Christiania 1873-75, p. 163. 



