38 KEY TO GENERA AND SPECIES 



lar, usually less than | of an 

 inch thick Sumach, 182. 



72. Leaflets opposite. Bark deeply 

 furrowed Locust, 181. 



72. Leaflets alternate. Bark 



smooth and gray. Tenn. 

 and adjoining area, also 

 cult. (Figs. 61, 62.) Yel- 

 low Wood, Cladrastis lutea 



(Michx. f .) Koch. Yellow Wood. 



73. Juice milky. Pith occupying more than half 



the diameter of the youngest branches 

 Sumach, 182. 



73. Juice not milky. Pith not occupying half the 



diameter of the youngest branches 74. 



74. Fruit fleshy, red, globular; less than \ inch 



thick; in flat-topped clusters. Leaflets com- 

 monly more than n. Bark of trunk usually 

 smoothish Mountain Ash, 157. 



74. Fruit a dry nut, \ inch or more thick. Leaflets 



either less than u, or else the bark of the 

 trunk prominently furrowed 75. 



75. Exterior husk of fruit not splitting away 



at maturity. Nut roughened with jagged 



