ROSACEAE 



The Hawthorns 

 Characteristics of the Genus Crataegus L. 



HABIT. Deciduous shrubs or small trees; usually spiny; 

 crown generally rounded and wide-spreading. 



LEAVES. Alternate; simple; deciduous; usually serrate and 

 often more or less lobed; membranaceous to coriaceous; stipules 

 persistent until autumn or deciduous in spring, small to leaflikc, 

 often bright-colored; petiolate. 



FLOWERS. Regular; perfect, in few- or many-flowered ter- 

 minal corymbs; pedicellate; calyx 5-lobed, tubular, persistent 

 on fruit or deciduous; corolla 5-petaled, white, inserted on 

 edge of disk lining calyx-tube; stamens 5-25; ovary inferior, 

 of 1-5 carpels connate at base, with 2 ovules in each cell; styles 

 as many as carpels. 



FRUIT. Small, variously colored pome with 1-5 bony, 1- 

 seeded nutlets; flesh usually dry and mealy; generally open or 

 concave at apex. 



TWIGS. Round; rigid; more or less zigzag; generally armed 

 with stiff, sharp thorns; marked by oblong lenticels and small 

 leaf scars. Winter buds: terminal usually present; small, glo- 

 bose, scaly, lustrous, brown. 



BARK. Dark red to gray; scaly or shallowly furrowed. 



WOOD. Heavy; hard; tough; close-grained; diff'use-porous ; 

 heartwood red-brown; sapwood thick, light-colored; unimpor- 

 tant; used for tool handles, canes, and turned articles. 



SILVICAL CHARACTERS. Intolerant; reproduction ag- 

 gressive; growth slow. 



GENERAL. An extremely large and complex genus contain- 

 ing over a thousand species, the identification of which presents 

 great diffiulties even to the specialist; hybridizing is common, 

 the number of stamens, which is variable but usually within 

 constant limits, and the color of the anthers appear to be the most 

 satisfactory characters for the identification of species. Some 

 149 species have been listed as trees in the United States and 

 Alaska; of these C. douglasii Lindl., the black hawthorn, which 

 is common through the west, has been pictured on the opposite 

 page as being typical of the genus. 



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