b c d 4 e 2 34 



g Leaf-buds with rusty appressed hairs; Ifts. glabrate ab.; teeth spreading. 



LARGE-FRUITED MOUNTAIN ASH (S. scopulina). 

 g2 Leaf-buds whitish tomentose; Ifts. pubescent. 



ROWAN TREE (Sorbus Aucuparia) . 

 es Leaflets 11-19 and 



f Sessile, viscid-pubescent as is all new growth; fr. nut with indehiscent 



husk BUTTERUNT (Juglans cinerea) . 



f2 Petiolulate, glabrous and leaf-stems spiny bn. ; fr. capsule. 



PRICKLY ASH (Xanthoxylum Clava-Herculis). 

 e* Leaflets 13-25, 



f Lance-ovate and green bn. ; twigs glabrate; a large tree; fr. nut with 



indehiscent husk BLACK WALNUT (Juglans nigra). 



f- Lanceolate, pale pubescent bn.; twigs velvety; a small tree; fr. drupelets 



with crimson hair STAG-HORN SUMACH (Rhus hirta) . 



c 2 LEAVES OPPOSITE; LEAFLETS 



d 3-7, entire at base, serrate or serrate lobed above; fr. samaras obliquely winged 



and in pairs jointed together at b Box ELDER (Acer Negundo). 



d2 5-11 and fr. a straight samara with terminal wing. 



e Samara with seed-bearing portion flattened and wing extending the entire 



length 

 f Lateral leaflets sessile; calyx in the fertile flowers none. 



BLACK ASH (F. nigra). 

 f2 Lateral leaflets stalked; calyx present 



