Practical Orcharding On Rough Lands. 53 



we see a whole mountain side covered with a 

 peach orchard, and a late spring frost will kill 

 all the fruit for a certain distance up the 

 mountain side, the rest of the trees being loaded 

 with fruit. This is sometimes so marked that 

 there may be seen a well defined line just at 

 a certain level where the work of the frost has 

 ceased. 



We are reminded of frost or air drainage 

 frequently when driving through the country 

 after nightfall, and notice how much cooler it 

 is at the mouth of a hollow than it was just be- 

 fore we came to it. All these instances show 

 how the cold air (which is heavier than the 

 warm air) is settling to the low lands, or 

 draining off just as water would. 



Now we would not be misunderstood in the 

 matter of air drainage and leave the impression 

 that altitude is the necessary factor. An or- 

 chard site may be on the top of a mountain at 

 an elevation of acoo fee. above Ae .ea level, 

 and yet not have good air or frost drainage. 



Again it is possible that an orchard site may 

 be located at an elevation of only 500 feet above 

 the sea level, aad yet escape the frost more fre- 

 quently than the one at an elevation of 2000 

 feet. Because in the case of the one on the 

 high mommin, it might be situated on a large 



