ADDISONIA . 79 
(Plate 80) 
ASTER CORDIFOLIUS 
Blue Wood Aster 
Native of the eastern United States and Canada 
Family CARDUACEAE THISTLE Family 
Aster cordifolius I,. Sp. Pl. 875. 1753. 
A perennial herb, commonly two to four feet high, with flexile 
freely branching stems that are glabrous or nearly so. The leaves 
are dull green, thin, somewhat rough to the touch on the upper 
surface, and are rarely without some small scattered hairs both 
above and beneath. ‘Those of the main stem are heart-shaped 
and acuminate, with serrate margins, the blades borne on slender 
stalks that are minutely ciliate. Upwardly the leaves become 
gradually shorter stalked and less deeply cordate, on the stems 
taking an even margin and narrowed sessile base. The numerous 
heads, in panicled clusters, are from one half to three quarters of an 
inch broad, their involucral cup cylindric, becoming slightly 
broadened above, and composed of linear-oblong bracts having 
greenish tips. ‘The rays, ten to twenty in number, are, in different 
plants, of various, usually pale, shades of violet or blue. The small 
clusters of disk flowers are yellow changing to purplish rose color. 
Perhaps no other groups of our native plants have found clearer 
reflection in the poetry and literature of our country than the asters 
and goldenrods, and yet, outside of botany, the very numerous 
members of these companion groups remain little known. The 
aster of our illustration finds its place somewhere between the more 
showy kinds and the host of smaller white flowered forms that, 
more especially, are collectively known as Michelmas daisies. It is 
of wide range, from New Brunswick to Minnesota, and south to 
Missouri and the mountains of Georgia, and in its places of abund- 
ance is a prominent although unostentatious member of its tribe. 
Its flowers are very numerous, and more than in most of our asters 
are disposed to top the leafy stems and branches in dense clusters. 
The plants, too, like to come together in extensive groups, by this 
habit producing massed effects of color along thickets and wood 
borders that become a feature of the late autumn; for it 1s among 
the later asters and well resists the advancing season. a 
This is one of those plants whose variations take it into wide 
divergencies, and even confused relationships with allied species, 
giving problems about which botanists are not yet agreed. So 
