68 The Rufted Grouse 



ground cover is more luxuriant when the crown allows plenty of 

 light to penetrate to the ground. 



There are many other variations of the hardwood type, some of 

 considerable importance to grouse. If the woods is pastured, the 

 woody understory is likely to be absent; hence this factor may be 

 important in grouse range. The species composition may be very 

 important depending mainly upon the inclusion of staple food pro- 

 ducers. Some of the more prevalent hardwood compositions in the 

 Northeast are: northern hardwoods (birches, maple, serviceberries, 

 poplar, black cherry, hophombeam); northern Appalachian hard- 

 woods (beech, birches, maples, cherries, poplars, serviceberries, 

 oaks, hophombeam, hornbeam); Appalachian hardwoods (oaks, 

 hickories, gums, serviceberry, hophombeam); mixed oaks. These 

 are the more prominent tree species in the hardwood types that 

 occur in plant growth zones from Canada to Virginia. 



The shrubs found in the understory of these subtypes vary too. In 

 the North, witchhobble {V. alnifolium) , withe rod (V. cassinoides) , 

 nannyberry (V. lentago), are prominent; in the middle region, 

 mapleleaf viburnum (V. acerifolitim) , poison ivy, blueberries, grape 

 are among the commoner species; while to the south flowering dog- 

 wood, mountain laurel, greenbrier, blueberries, honeysuckle, poison 

 ivy, and grapes are common. There are also minor differences in the 

 ground cover. Bunchberry [Corrms canadensis), ferns, Canada may- 

 flower, violet, wood sorrel, jewelweed, shinleaf, miterwort, false 

 miterwort, skunk cabbage, and hepatica are significant in the North; 

 while to the south the ferns, lespedezas, hepatica, alumroot, skunk 

 cabbage, wood sorrel, and false miterwort are among the more im- 

 portant plants. 



Mixed woodland: The difference between the mixed woods and 

 the hardwood types lies primarily in the tree composition, and in 

 the proportion of conifers in the mixture. From the standpoint of 

 grouse needs, the hardwood types are deficient in conifers. Most of 

 the areas of the hardwood type have no conifers at all, or but a 

 scattered few. These areas are clearly conifer-deficient, but what 

 about stands that have five per cent, ten per cent, fifteen per cent and 

 so on, of conifers? Since we cannot interpret the reactions of grouse 

 to shelter with such fine accuracy, and since these reactions will vary 

 under different conditions, we have to be somewhat arbitrary in 

 drawing the line between the two type groups. However, twenty 

 per cent of conifers appears to be a proper proportion. 



