Descriptive Flora 



231 



Helianthus annus L. Sunflower. "Mirasol". "Girasol". 



Stout, rough, often purplish stemmed, fibrous, erect plants, 

 2 to 10 feet tall, having large yellow flowers, 2 to 5 inches across, 

 similar to the large cultivated sunflowers of our gardens. Upper 

 leaves simple, alternate. Blades broadly ovate, large, toothed, 

 rough-hairy, ovate, veiny beneath, heavily 3-veined at base. 

 Flowers composite, yellow with brownish-black centers, and 

 solitary on long rough stems. Rays many, yellow, 1 to 2 inches 

 long, toothless. March to fall. Widespread, often lining road- 

 sides for miles, and covering fields for hundreds of acres. Seeds 

 form food for many birds. Well named as the flower follows the 

 sun. 



Helianthus cucumerifolius Torr. & Gray. 



Similar in general appearance to the Common Sunflower. 

 Plants more slender-stemmed, stems and branches mottled with 

 purple, leaves smaller and thinner, and flowers with orange 

 rays and not as large (usually 2 to across). In the sandy 

 region to the south and east. 



Helianthus maximilianii Schrad. Maximilian's Sunflower. 



A tall, leafy plant with large, yellow, composite flowers 

 about y% across and blossoming in the fall. Leaves simple, alter- 

 nate. Blades firm, lanceolate varying to linear, 2 to 8" long, 

 tapering at both ends, entire (rarely toothed). Leafstalks very 

 short or none. Flowers solitary, terminating short lateral 

 branches on the upper part of the main stalk. Rays conspicuous, 

 slender, 1 to 1 long, 10 to 23. Disk y 2 to %" across. Bracts of 

 the involucre % to 1 inch long, lanceolate, with conspicuous 

 slender tips. Achenes flat, 2-awned. Receptacle chaffy. Sep- 

 tember and October. In low grounds. Often planted like the 

 Goldenrod for ornament. 



Encelia calva Gray. 



Rough-stemmed plants, with yellow composite flowers and 

 simple, opposite leaves, the petioles joined at the base on each 



