CRATAEGUS 



155 



No critical work has as yet been done on Minnesota Crataegi and for 

 that reason it has been thought advisable to adhere only to the broader 

 concept of species in this work. It is therefore to be expected that after 

 more extensive collection and careful systematic work several more species 

 will be credited to the state. 



Key to the Species. 



1. Leaves ovate, elliptic-ovate or nearly orbicular 



in outline, mostly lobed, more than 4 cm. wide 



a. Leaves cordate to truncate at the base, densely 



tomentose below, fruit pubescent C. mollis 



b. Leaves cuneate at the base, glabrous or 



pubescent, fruit glabrous 



( 1 ) Leaves ovate-orbicular, coarsely serrate, 



glabrous on both sides C. rotundij olia 



(2) Leaves rhombic-elliptic, pubescent, at 



least on the veins beneath coarsely 

 serrate 



(a) Leaves coriaceous, dark green and shin- 



ing above C. macracantha 



(b) Leaves thin, dull green, pubescent and 



with impressed veins above C. tomentosa 



2. Leaves obovate, oblanceolate, or spatulate, 



slightly or not at all lobed, mostly 2-4 cm. 

 wide 



a. Leaves dull, gray-green, pubescent C. punctata 



b. Leaves bright green, glabrous and shining C. crus-galli 



Crataegus mollis (Torrey and Gray) Scheele 1845 Red-fruited 



Thorn 



A shrub or small tree 2-7 meters (6-21 ft.) high; branches armed with 

 thorns 3-6 cm. long, lustrous, or at last grayish ; bark of trunk ashy gray ; 

 leaves broadly ovate, cordate to truncate at the base, acutish at the apex, 

 lobed, sharply and rather coarsely serrate, rough above, densely tomentose 

 below, 4-13 cm. long, 4-10 cm. wide; corymbs several- to many-flowered; 

 flowers white, about 2 cm. broad, pedicels and calyx densely tomentose, 

 stamens about 20; fruit sub-globose, scarlet, 1.5-2 cm. in diameter, 

 pubescent when young, flesh yellow, nutlets usually 5, 7-8 mm. long, drop- 

 ping off as soon as ripe : mollis, soft, referring to the leaves. 



