CELTIS 87 



a. Shrub with buds 1-2 mm. long; 



drupes 5-8 mm. long 2. C. tenuifolia 



1. C. occidentalls L. Hackberry . A tree 8-28 m.high, up to 

 7.5 cm. in diameter, the bark black, rough, corky-ridged or 

 warty; buds 3-4 mm. long; drupes sweet and edible, 8-10 mm. in 

 diameter, the flesh thin. Rich woods, Quebec to Idaho, south to 

 Florida and Oklahoma (Fig. 85). 



2. C. pumila Pursh. Dwarf Hackberry . Alow straggling 

 shrub, often fruiting copiously when but 6-9 dm. high; twigs brown; 

 buds 1-2 mm. long; drupes globose. Dry slopes, Quebec to North 

 Dakota, south to Georgia and Oklahoma (Fig. 86). 



MORUS L. (Moraceae) 



Deciduous trees with milky sap. Twigs moderate, rounded; 

 pith moderate, round, continuous. Buds sessile, solitary or mul- 

 tiple, ovoid, oblique, with 3-6 scales; end -bud lacking. Leaf-scars 

 alternate, round or half-round; bundle-traces numerous, scattered 

 or in 3 groups; stipule-scars narrow. 



a. Buds elongated, 6-8 mm. long, somewhat 



spreading 1. M. rubra 



a. Buds triangular-ovoid, short and 



closely appressed 2. M. alba 



1. M. rubra L. Red Mulberry. A tree 5-20 m. high, up to 

 2 m. in diameter; bark brown and rough; twigs often downy; buds 

 spreading, 6-8 mm. long; bud -scales brown-margined. Rich 

 woods, Ontario to Minnesota and South Dakota, south to Florida 

 and Texas (Fig. 87). 



2. M. alba L. White Mulberry . A small tree, sometimes 14 

 m. high and 1 m. in diameter; bark light gray, rough, the branches 

 spreading; buds appressed, 3-4 mm. long; bud-scales generally 

 uniformly colored. Introduced from Europe, much spread from 

 cultivation and naturalized (Fig. 88). 



BROUSSONETIA L'Her. (Moraceae) 



Small deciduous trees with milky sap. Twigs moderate, 

 rounded; pith large, white, with a thin green diaphragm at each 

 node. Buds moderate, conical, solitary, sessile, the outer scale 

 longitudinally striped. Leaf-scars alternate, 2-ranked, large, 

 rounded; bundle-traces about 5; stipule-scars long and narrow. 



1. B, papyrifera (L. ) Vent. Paper Mulberry . A tree some- 



