This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol3", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
Aster tenuifolius L. Sp. Pl. 873. 1753. Aster flexuosus Nutt. Gen. 2: 154. 1818.
Perennial, glabrous and fleshy; stem flexuous, striate, at least when dry, sparingly and loosely branched, 1°-2° high. Stem leaves linear, entire, acute, sessile or partly clasping at the base, the lowest lanceolate-linear, 2'-6' long, 2"-3" wide, those of the branches minute, bract-like, ap-pressed; heads rather few, 6"-12" broad, terminating the branches; involucre turbinate, about 4" high, its bracts lanceolate, acuminate or mu-cronate, glabrous, green on the back or tip, ap-pressed, imbricated in about 5 series, the outer shorter; rays numerous, longer than the pappus, pale purple or nearly white; pappus tawny; achenes hispid-pubescent, 5-nerved.
In salt marshes, coast of Massachusetts to Florida. Aug.-Oct.
Aster exilis Ell. Bot. S. C. & Ga. 2: 344. 1824.
Aster divaricatus T. & G. Fl. N. A. 2: 163. 1841. Not L. 1753.
Annual, glabrous, fleshy; stem slender, usually much branched, the branches usually divergent. Leaves linear to linear-lanceolate, 1'-4' long, 1"-21/2" wide, entire, sessile, acute or acuminate, or the lowest narrowly oblong, 3"-4" wide and petioled, those of the branches subulate; heads numerous, panicled, about 5" broad; involucre campanu-late, about 3" high, its bracts linear-subulate, appressed, imbricated in 3 or 4 series; rays purplish, about 2" long, mostly fewer than the disk-flowers, longer than the pappus; achenes somewhat pubescent.
In moist or wet soil, especially in saline situations, Kansas to Texas, South Carolina and Florida. Bahamas; Cuba. Aug.-Oct.
Aster subulatus Michx. Fl. Bor. Am. 2: I I I. 1803. Aster linifolius T. & G. Fl. N. A. 2: 162. 1841. Not L. 1753.
Annual, glabrous and fleshy; stem paniculately branched, flexuous above, 1°- 6° high, slightly angled, sometimes 1' in diameter at the base, but usually smaller. Stem leaves linear-lanceolate, acute, entire, sessile by abroad or slightly clasping base, 2'-10' long, 1"-8" wide, those of the branches very small and subulate; heads numerous, 3"-S" broad; involucre campanulate, or at length hemispheric, 2"-3" high, its bracts linear-subulate, green, imbricated in 3 or 4 series, the outer shorter; rays 20-30, purplish, scarcely exceeding the nearly white pappus, more numerous than the disk-flowers; achenes compressed, minutely pubescent.
In salt marshes, coast of New Brunswick to Florida. Also on salt lands Onondaga Lake, N. Y. Aug.-Nov.