STATE POMOI.OGICAL SOCIETY. 33 



considerations in selecting orchard sites in their relation to 

 successful orcharding. To a great many it is a more or less 

 unintelligible thing, this matter of atmospheric drainage. Two 

 or three slides will perhaps show the effect of atmospheric 

 drainage in such a way that even if you cannot see it you can 

 get a very vivid idea of its results. (A view of an orange tree 

 in Florida was here thrown on the screen.) This shows a condi- 

 tion which the tree displayed following a severe freeze which 

 occurred in Florida a few years ago. You know after a very 

 severe frost occurs while plants are in active growth the 

 leaves will be killed and will dry right up on the tree without 

 falling off. That is a common observation. If slightly injured, 

 enough just barely to kill them, they will drop in a little time. 

 These conditions were apparent in the case of this orange tree. 

 The lower leaves were killed so entirely that they dried up 

 on the tree without falling off. In the middle portion of the 

 tree, the leaves were injured just enough to kill them, so that 

 they dropped. The top of the tree was uninjured, thus showing 

 three gradations in temperature — three climatic conditions, if 

 you please — within the height of the tree. 



The next view shows atmospheric drainage in another 

 manner, in a large mountain peach orchard in West Virginia. 

 The picture was taken in the morning, with a fire burning on 

 the side of the mountain. The smoke is seen drifting down the 

 hill showing simply that the current is downward; in other 

 words, a visible illustration of atmospheric drainage. 



Atmospheric drainage is further illustrated by two views 

 of an apple orchard in West Virginia. There was an interval 

 of one week between the dates on which the photographs were 

 taken. The views show a depression between the point where 

 the photographs were taken and the remote portion of the or- 

 chard, that portion being elevated 50 feet or such a matter 

 above the lowest point of the depression. The earlier view 

 shows the trees in the distance in full bloom, while those in 

 the depression had not yet come into bloom. The second view 

 displays the same orchard a week later, showing the trees in 

 the distance on the elevated portion of the orchard going out 

 of bloom, while those in the depression were in full bloom. A 

 comparison of these two views makes it apparent that there 

 vvere really two climates within the short distance indicated in 

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