DISTRIBUTION AND HABITAT REQUIREMENTS OF GROUSE FOOD PLANTS 225 



Monthly Variations in Summer Chick Foods 



From June through August there is a progressive change from an animal to a vegetable diet. 

 At first the ])lant foods are few in number and consist for the most part of the smaller seeds 

 and bits of easily reached plants. Feeding activity during the first ten days after hatching 

 consists largely of catching ants and beetles and occasionally capturing a juicy caterpillar, 

 interspersed with the diligent striijping of sedge seeds and sampling of strawberries. 



By July animals make up only a tenth of the food and the birds are patronizing a wide 

 variety of plants, even including some fruit-bsaring trees. The consumption of blackberries, 

 the bushes of which provide both food and shelter, rose rapidly and amounted to 42.1 per 

 cent of the total for the month. This gain was largely at the expense of animal foods, which 

 dropped from 56.6 per cent in June to 13.0 per cent in July. The foraging becomes still 

 farther diversified in August and in later summer the young tend progressively to take about 

 the same foods as do the adults. 



The monthly variations of the most ini|)r)rtanl |)lant and animal foods of chicks are indi- 

 cated in table 31. 



DISTRIBUTION AND HABITAT UFQUIREMFNTS OF GROUSE FOOD PLANTS 



Plants furnishing food for grouse at one or more seasons of the year are to be found, 

 often in abundance and \arietv in incisl overgrDwn fields and woodlands throughout the 

 Northeast. Some, such as \aric)us species of wild cherries. as|)ens. liiaikberrie.s. raspberries, 

 birches, sumachs and thornapples, which together supply It! per cent of all grouse food, 

 occur in every region of the State. They thrive on almost all types of soil, from sand to clay, 

 from rich to poor, from wet to dry. For most of them, the one common requirement ap- 

 pears to be an absence of strong competition for growing space, for many characteristically 

 occur in the earlier stages of plant succession, as on cutover or overgrown lands. 



Pin cherries, aspens, gray and black birches and sumachs are short-lived plants intolerant 

 to shade. They build up a ground cover and prej)are the way for the more shade tolerant 

 and longer-lived species such as black cherry, ash. yellow birch. l)eech and maple, which 

 follow them and ultimately shade them out. Other grouse food plants of overgrown lands 

 as apple, thornapple, shadbush and hop-hoinbeam are perhaps more resistant to shading 

 and therefore may persist for a longer lime under the closing forest canopy. Only a few 

 such as the mountain and the striped nia|)Ies. are t\|)i(allv understorv shrul)s which thrive 

 in relatively dense shade. 



Of the many plants eaten in large (]uantities by grouse, but few are limited as to dis- 

 tribution in New York by soil or climatic factors. Of the birches, neither black nor gray 

 is found widely in the Adirondacks, nor is the latter conspicuous far west of the Hudson 

 Valley. Hop-hornbeam is most abundant in central New York; less so in the mountains 

 and on Long Island. Huckleberry, blueberry, bunchberry and wintergreen thrive on mod- 

 erately to strongly acid soils. Partridge-berry and evergreen wood ferns reach their best 

 development in the duff of the forest floor. 



In table 32 are recorded some of the habitat preferences and other characteristics of ruffed 

 grouse food plants. 



Though many of the species may be widelv distributed, most are restricted more or less 

 to certain stages in plant succession. 



Grouse habitats are made up of plant associations. For convenience in identification we 



