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KEY TO THE SPECIES BASED PRIMARILY ON FRUIT AND BUDS. 



Page. 



1. Acorns maturing at end of second season -on last season's growth; immature acorns 

 may be present in winter; shell of nut hairy inside; scales on acorn-cup usually 

 broad and thin, 2 



1. Acorns maturing at end of first season on growth of season; immature acorns never 



present in winter; shell of nut not hairy inside; scales of acorn-cup more or less 

 knobby ...10 



2. Buds large; terminal ones usually over one-fifth of an inch long, 3 



2. Buds smaller; terminal ones one-fifth of an inch or less in length, 7 



3. Buds coated with rusty brown hairs prominently angled, 4 



3. Buds not coated with msty brown hairs; not prominently angled 5 



4. Inner bark yellow; buds i-$ of an inch long; acorn-cup top-shaped to hemispheric, 



Q. velutina 142 



4. Inner bark not yellow; buds i of an inch long or less; acorn-cup hemispheric 



Q. marilandica 145 



5. Buds sharp-pointed, 6 



5. Buds blunt-pointed, the widest part, at or just below middle; evidently woolly above 



middle, Q. coccinea. 141 



6. Acorn-cups saucer-shaped; buds glabrous except sometimes slightly hairy near apex; 



bark fissured with intervening broad smooth ridges; branches straight, . ...Q. rubra 139 



6. Acorn-cups hemispheric; buds light brown and hairy; bark shallowly fissured, with 



scaly ridges, brarching zigzag Q. falcata 143 



7. Twigs during first winter dull, finally hairy; shrubs, Q. ilicifolia 144 



? Twigs smooth and shining during first winter; trees, 8 



8. Pin-like projections oi< lateral branches numerous, standing almost at right angles to 



branch; trunk continuous; acorn-cup saucer-shaped, Q. palustris 140 



8. Pin-like projections not present; trunk divided 9 



9. Acorn-cups saucer- shaped; buds dark brown; twigs stouter, Q. phellos 147 



9. Acorn-cups hemispheric; buds light brown and angular; twigs slender, ..Q. imbricaria 146 



10. Buds narrow, conical, sharp-pointed, 1 of an inch or more in length, 11 



10. Buds obtuse, short, usually about J of an inch long, 13 



11. Buds pubescent, usually sharp-pointed, lateral buds generally appressed; bark on 



older twigs with corky ridges; acorn-cups fringed, Q. macrocarpa 134 



11. Buds smooth, lateral buds divergent; twigs without corky ridges; acorn-cups not 



fringed 12 



12. Acorns sessile; twigs slender and hairy to smooth, Q. Muhelnbergii 136 



12. Acorns evidently stalked; twigs stouter and smooth, Q. Prinus 137 



13. Bark on branchlets peeling into long, dark, layer-like scales; acorns long stalked, 



Q.bicolor 135 



13. Bark on branchiate not peeling off into long, dark, layer-like scales, 14 



14. Twigs usually coated with yellowish-brown wool; buds about as long as broad, 



Q. stellata 133 



14. Twigs smooth 15 



15. Twigs slender; shrub or small tree; buds about as long as broad; acorn-cup enclose* 



i of nut, Q. prinoides 138 



15. Twigs stout; large tree; buds longer than broad; acorn-cup encloses J of nut,..Q. alba 132 



