YELLOWSTONE NATIONAL PARK 

 (blue or white) (blue) 



57 



GIANT ASTER 



Aster (Aster). There are so many kinds of wild 

 aster in the Park, distinguishable only by profession- 

 al botanists, that it is not worth while to describe 

 them separately. Though the size of the flower varies 

 greatly, ranging from one-quarter inch to over two 

 inches in diameter, the general appearance is the 

 same. The disk at the center is yellow, and the petals, 

 or more properly speaking, rays, are usually blue but 

 occasionally white. Stem and leaf habits vary greatly 

 in the different species, and habitat preferences also; 

 asters are found everywhere from the semi-desert hills 

 to moist, wooded ravines. Asters are fall flowers, be- 

 ginning early in July and continuing even after frost. 



Giant Aster (Toumsendia) . This flower is not a 

 true aster, though it strongly resembles the asters; 

 still, its striking and peculiar appearance makes it 

 worth separate mention. It grows in dry, exposed 

 places, and, like many desert plants, confines its leaves 

 to a basal rosette. The leaves are small, narrow, pad- 

 dle-shaped, and rather hairy. The flower is nearly 

 three inches in diameter, with a yellow disk about an 

 inch across. They are borne on short, thick stems, 

 two or three to a plant. 



