From Blue to Purple 



selection of the fittest among their ancestral types, having finally 

 arrived at the most successful adaptation of their various parts 

 to their surroundings in the whole floral kingdom, they are now 

 overrunning the earth. Doubtless the aster's remote ancestors 

 were simple green leaves around the vital organs, and depended 

 upon the wind, as the grasses do — a most extravagant method — 

 to transfer their pollen. Then some rudimentary flower changed 

 its outer row of stamens into petals, which gradually took on 

 color to attract insects and insure a more economical method of 

 transfer. Gardeners to-day take advantage of a blossom's natural 

 tendency to change stamens into petals when they wish to pro- 

 duce double flowers. As flowers and insects developed side by 

 side, and there came to be a better and better understanding be- 

 tween them of each other's requirements, mutual adaptation fol- 

 lowed. The flower that offered the best advertisement, as the 

 composites do, by its showy rays ; that secreted nectar in tubu- 

 lar flowers where no useless insect could pilfer it ; that fastened 

 its stamens to the inside wall of the tube where they must dust 

 with pollen the under side of every insect, unwittingly cross-fer- 

 tilizing the blossom as he crawled over it ; that massed a great 

 number of these tubular florets together where insects might 

 readily discover them and feast with the least possible loss of 

 time — this flower became the winner in life's race. Small wonder 

 that our June fields are white with daisies and the autumn land- 

 scape is glorified with golden-rod and asters ! 



Since North America boasts the greater part of the two 

 hundred and fifty asters named by scientists, and as varia- 

 tions in many of our common species frequently occur, the tyro 

 need expect no easy task in identifying every one he meets afield. 

 However, the following are possible acquaintances to every one : 



In dry, shady places the Large, or Broad-leaved Aster (/4. ma- 

 crophyllus), so called from its three or four conspicuous, heart- 

 shaped leaves on long petioles, in a clump next the ground, may 

 be more easily identified by these than by the pale lavender or 

 violet flower-heads of about sixteen rays each which crown its 

 reddish angular stem in August and September. The disk turns 

 reddish brown. 



In prairie soil, especially about the edges of woods in western 

 New York, southward and westward to Texas and Minnesota, 

 the beautiful Sky-blue Aster {A. a^ureus) blooms from August till 

 after frost. Its slender, stiff, rough stem branches above to display 

 the numerous bright blue flowers, whose ten to twenty rays 

 measure only about a quarter of an inch in length. The upper 

 leaves are reduced to small flat bracts ; the next are linear ; and 

 the lower ones, which approach a heart shape, are rough on both 

 sides, and may be five or six inches long. 



Much more branched and bushy is the Common Blue, Branch- 

 ing, Wood, or Heart-leaved Aster (yf. cordifolius), whose generous 



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