Bodies of Water 47 



frost-injury in spring is often due more to the retardation 

 of the period of bloom than to the actual prevention of 

 frost, although its influence in the latter direction is 

 important. The lands adjacent to the water ordinarily 

 warm up later in spring, and the trees are not likely, 

 therefore, to swell their buds until danger of serious frosts 

 is past. The extent of this retardation of bloom is often 

 as great as ten to twenty days within a stretch of 10 or 20 

 miles from a large body of water. 



It is well known that the danger from frosts is greatest 

 in mild climates, in which "warm spells" are likely to 

 occur in late winter or early spring. In the central and 

 southern states, this frost injury following a period of 

 warm weather is commoner than true winterkilling, 

 whereas in the northernmost states and Canada serious 

 injury to the trees from late spring frosts is comparatively 

 infrequent. In the northern states, also, the plant usually 

 goes into -the winter in a perfectly dormant and ripened 

 condition, and is thereby able to withstand great cold. It 

 has been said that injury from cold is more frequent in the 

 Gulf states than in New York. 



The elevation of any place also stands in close relation 

 to frostiness. Perfectly flat lands are nearly always frosty, 

 because there is no atmospheric drainage, a subject to 

 which we shall soon recur. On the other hand, very high 

 lands are also frosty, because the air is drier and rarer 

 and therefore allows of rapid radiation of heat from the 

 land; and they are exposed to cold, unbroken winds. 

 The local altitude to which the fruit-lands may be carried 

 can be determined only by actual experiment ; but in the 

 North the best elevations for the tender fruits are usually 

 between 100 and 300 feet above the local rivers or lakes. 



While it is extremely important that the location for 



