KEY TO THE GENERA 15 



q. Leaves not fragrant 



(p) Leaves crowded at the 



tips of twigs Menziesia 89 



(q) Leaves not crowded at 

 the tips of twigs 



e. Cultivated shrubs Spiraea : spiraea 128 



f. Native shrubs 



(e) Tall shrub, leaves 



over 5 cm. long Alnus: alder 254 



(f) Low shrub, leaves 



less than 5 cm. 

 v. Swamp shrub Betula : birch 246 



w. Shrubs of dry 



ground Amelanchier : juneberry 150 



(i) Leaves acute to long-point- 

 ed at tip 

 p. Leaves long-pointed 



(p) Leaves broadly ovate Corylus: hazel-nut 241 



(q) Leaves lanceolate to 



linear Salix : willow 59 



q. Leaves acute but not long- 

 pointed 

 (p) Fruit fleshy 



e. Fruit with a single stone Primus : plum, cherry 163 



f. Fruit several-seeded 



(e) Fruits solitary or 



1-3 in a cluster 



v. Fruit red Ilex: wintcrberry 213 



w. Fruit black, some 

 leaves often op- 

 posite Rhammus: buckthorn 197 



(f) Fruits several or 



many in a loose 

 cluster 

 v. Fruit ripening in 



mid-summer Amelanchier: juneberry 150 



w. Fruit ripening in 



the fall Aronia: chokeberry 153 



g. Fruit many-seeded Vaccinium: huckleberry 97 

 (q) Fruit dry 



e. Fruits in catkins ; seeds 



cottony Salix : willow 59 



f. Fruits in branched 



clusters Spiraea: spiraea 128 



(b) Leaves lobed 

 x. Leaves opposite 



(x) Petioles usually with stipules and glands Viburnum: viburnum 280 



(y) Petioles without stipules or glands 

 m. Leaves sharply and deeply lobed Acer: maple 219 



n. Leaves crenately lobed Symphoricarpus : snowberry 284 



y. Leaves alternate 



(x) Leaf margin entire 

 m. Vines with broad palmately veined 



leaves Menispermum : moonseed 50 



n. Low aromatic shrub with linear leaves Comptonia : sweet fern 269 



o. Low densely silky shrubs ; leaves with 



3-9 linear lobes Artemisia: wormwood 297 



(y) Leaf margin toothed 

 m. High-climbing vines 



(m) Tendrils coiling, without disks Vitis: grape 202 



(n) Tendrils attached by disks Parthenocissus : Boston ivy 203 



