172 The Ruffed Grouse 



Since the grouse is a browser, it is doubtful that it ever has to make 

 a choice of an emergency food. If any foods are accessible, some of 

 its regular articles of diet will be among them. No evidence of the 

 consumption of "stuflBng" or "salad" foods was obtained. As a mat- 

 ter of fact, it is difficult in many cases to distinguish between pre- 

 ferred and staple foods of the grouse. 



Some grouse foods, however, are clearly preferred. Beechnuts, red 

 haws, apple fruit or foliage, acorns, strawberry fruits and leaves, 

 bramble fruits, greenbrier berries, and grapes are so utilized, and 

 birch, apple, fern, popple, cherry, and blueberry are choice among 

 the leaf and bud foods. Certainly in a sense, birch buds are preferred, 

 as they are regularly taken in preference to many other equally 

 available foods of this type, as those from beech, maple, elm, ash, 

 and hickory, for example. Yet, it is likely that if beechnuts, hawthorn 

 fruits and certain other foods were available in winter much less of 

 birch buds would be taken. 



Preference must be interpreted with due regard to availability. 

 It is likely that chestnuts would be a preferred food if available, 

 since they probably once were of primary rank. Being absent now 

 over most of the range, they rank merely as an incidental food. 



Most of the foods listed above as primary and secondary may also 

 be considered staple, while those not so classed are ordinarily in- 

 cidental. 



VARIATION IN SUMMER FOOD HABITS OF YOUNG AND ADULTS 



The groups of plants and animals providing the bulk of the sum- 

 mer food are essentially the same for both adults and young. The 

 quantities taken by birds of these age classes, however, may vary 

 widely. Young birds in early summer consume a very high propor- 

 tion of animal food whereas the adults use only a moderate quantity. 

 The two topmost food-producing groups of plants, brambles ( Rubus ) 

 and sedges (Carex) are the same throughout New York for the 

 chicks. Rubus ranks first for adults, but one or the other of Carex, 

 cherries ( Prunus ) and popples ( Populus ) takes second place in dif- 

 ferent localities. The volume of raspberries used by chicks ( twenty- 

 nine per cent-thirty-eight per cent summer average ) greatly exceeds 

 that taken by adults. There are numerous other variations in summer 

 food habits between the adults and young, mostly, however, of minor 

 importance. 



