FIELD AND STUDY 



full of white moths for two seasons; then something 

 happened and these worms have not returned. 



Occasionally a favorable combination of weather 

 and seasonal conditions fills some parts of the coun- 

 try with a plague of grasshoppers, and the farmers 

 tremble for their next season's crops, but the next 

 season may prove quite grasshopperless. 



The tide in the affairs of some of our fruit and 

 tree pests, such as the gypsy and brown-tailed 

 moths and the San Jose scale, seems yet at its full, 

 but no doubt the ebb will come before the case is 

 hopeless. 



Ebb and flow, ebb and flow, everywhere in the 

 life of nature. When I lived upon the Potomac forty 

 years ago, the grass bunting, or dickcissel, was a 

 common bird in the fields. Some years later these 

 birds began slowly to disappear, and now that part 

 of the country is said to be destitute of them, while 

 they are common farther south in Kentucky and 

 Tennessee. What caused the disappearance or mi- 

 gration of these birds, who knows? 



Of late years the prairie horned lark has appeared 

 upon my native hills in the Catskills, where, in my 

 youth, they were never seen. Such game-birds as 

 the quail ebb and flow in New York and New Eng- 

 land, according as the winters are mild or severe. 

 Not many years ago a series of mild winters gave 

 the quail a great lift in the Hudson River Valley, 

 where I five. The call of Bob White lent a new charm 



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