56 TREES OP THE NORTHERN UNITED STATES 



c. Fruit large, orange-like in size and color when ripe ; juice 



milky 77. Madura. 



c. Fruit small, black when ripe, cherry-like ; juice milky .. . 



54. Bumelia. 



d. Aromatic ; berries dark blue on red stalks 68. Persea. 



d. Not aromatic ; leaves nearly 1 ft. long ; flowers large and soli- 

 tary 1. Magnolia. 



d. Not aromatic; leaves 1-4 in. long; flowers very small; fruit 



small dark-colored berries, with 2-4 seeds 20. Bhamnus. 



d. Not aromatic; flowers large, in showy clusters, (e.) 



e. Leaves 5 in. or more long 52. Rhododendron. 



e. Leaves less than 4 in. long 51. Kalmia. 



f. Leaves decidedly aromatic, usually somewhat irregularly lobed, 



margin entire, base tapering 69. Sassafras. 



f. Leaves usually deltoid, sometimes heart-shaped with serrate 

 margin and gummy buds, rarely palmately lobed. All have 

 either the petiole flattened sidewise, the leaf-blade densely 

 silvery-white beneath, or gummy aromatic buds. . . .92. Populus. 

 f. Leaves broadly heart-shaped ; margin entire ; small tree with 

 abundance of red flowers in early spring; fruit a pea-like pod 



32. Cercis. 



f. Leaves not as above given, (g. ) 



g. Leaves broadly heart-shaped, with a serrate margin and a 

 petiole about as long as the blade, sometimes longer ; base 



of leaf not oblique 4. Idesia. 



g. Leaves broadly heart-shaped, those on the suckers much 

 lobed ; base not oblique ; margin serrate ; juice milky; bark 

 very tough. (1. ) 

 g. Leaves broadly heart-shaped, with an oblique base ; margin 



regularly serrate ; juice not milky 11. Tilia. 



g. Leaves slightly if at all heart-shaped at base, usually some- 

 what oblique, with neither milky juice nor lobes, (j.) 

 g. Leaves decidedly and quite regularly lobed. (h.) 

 h. Leaves with 3-5 large lobes, the margin entire or slightly an- 



gulated 10. Sterculia. 



h. Leaves star-shaped, with 5-9 pointed, serrate lobes, (i.) 



h. Leaves large, irregularly margined; leaf -stem covering the 



bud ; large tree 80. Platanus. 



h. Plant quite thorny; fruit berry-like, ending in a conspicuous 

 spreading calyx ; small trees or shrubs with apple-like blos- 

 soms. 38. Cratsegus. 



h. Leaves with a tapering base; small tree, almost a shrub, 



with large Hollyhock-like flowers ; plant not thorny 



. . 9. Hibiscus. 



