The Manual of the Botany of the Northern United States - Part 90
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Part 90

Heads 12--20-flowered, radiate; the rays about 5, fertile (white).

Involucre somewhat cylindrical or club-shaped; the scales closely imbricated in several rows, cartilaginous and whitish, appressed, with short and abrupt often spreading green tips. Receptacle alveolate-toothed. Achenes short, inversely pyramidal, very silky; pappus simple, of numerous capillary bristles.--Perennial tufted herbs (1--2 high), with sessile somewhat 3-nerved leaves, and small heads mostly in little cl.u.s.ters, disposed in a flat corymb. Disk-flowers pale yellow. (Name from s??????, _silky_, and ?a?p??, _fruit_.)

[*] _Pappus rusty; leaves sparingly serrate, veiny, rather thin._

1. S. conyzodes, Nees. Somewhat p.u.b.escent; leaves oblong-lanceolate or the lower spatulate, ciliate; heads rather loosely corymbed, obconical (4--6" long).--Dry ground; Maine to Ohio, and southward. July.

[*][*] _Pappus white; leaves entire, obscurely veined, firmer and smaller._

2 S. solidagineus, Nees. Smooth, slender; leaves linear, rigid, obtuse, with rough margins, tapering to the base; heads narrow (3" long), in close cl.u.s.ters, few-flowered.--Thickets, S. New Eng. to Tenn., and southward. July.

3. S. tortiflius, Nees. h.o.a.ry-p.u.b.escent; leaves obovate or oblong-spatulate, short (--1' long), vertical, both sides alike; heads rather loosely corymbed, obovoid (4--5" long).--Pine woods, Va. and southward. Aug.

25. aSTER, L. STARWORT. ASTER.

Heads many-flowered, radiate; the ray-flowers in a single series, fertile. Scales of the involucre more or less imbricated, usually with herbaceous or leaf-like tips. Receptacle flat, alveolate. Achenes more or less flattened; pappus simple, of capillary bristles (double in ---- 4 and 5).--Perennial herbs (annual only in ---- 7 and 8), with corymbed, panicled, or racemose heads; flowering in autumn. Rays white, purple, or blue; the disk yellow, often changing to purple. (Name ?st??, _a star_, from the radiate heads of flowers.)

Conspectus of Groups.

Annuals, with copious fine soft pappus 53, 54

Pappus double 46--48

Scales closely imbricated, not green-tipped, often scarious-edged 49--52

Scales closely imbricated, scarcely at all herbaceous; leaves cordate, serrate 2, 3

Scales nearly equal, rigid, more or less foliaceous; pappus-bristles rigid, some thickened at top 1

Scales with herbaceous tips or the outer wholly foliaceous.

ASTER proper.

Pappus rigid; stem-leaves sessile, none cordate or clasping; heads few, large 4--8

Leaves silvery-silky both sides, sessile, entire 14, 15

Lower leaves more or less cordate, petiolate 17--24

Leaves entire, lower not cordate, cauline sessile with cordate-clasping base 16

Involucre (and branchlets) viscid or glandular; leaves not cordate, mostly entire, the cauline all sessile or clasping 9--13

Lower leaves all acute at base; not glandular nor viscid nor silky-canescent.

Smooth and glabrous, usually glaucous; scales coriaceous at base; leaves firm, usually entire 25--30

h.o.a.ry-p.u.b.escent or hirsute; scales squarrose; stem-leaves small, linear, entire 31, 32

Scales closely imbricated, not coriaceous at base; branches divaricate; heads many, small 33--35

Remaining species; branches erect or ascending.

Stem-leaves auriculate-clasping or with winged-petiole-like base; involucre lax 42--45

Stem-leaves sessile, but rarely cordate or auriculate at base 36--41

-- 1. HELIaSTRUM. _Pappus simple, coa.r.s.e and rigid, the stronger bristles somewhat clavate; scales rigid, more or less foliaceous, nearly equal._

1. A. paludsus, Ait. Stems 1 high; glabrous or nearly so; heads '

high, rather few, racemose or spicate; outer scales lax, foliaceous; rays purple; leaves linear, entire.--Mo. to Tex., thence to Car. and Ga.

-- 2. BITIA. _Involucre obovoid-bell-shaped; the scales regularly imbricated in several rows, appressed, nearly dest.i.tute of herbaceous tips; rays 6--18 (white or nearly so); achenes slender; pappus slightly rigid, simple; lower leaves large, heart-shaped, petioled, coa.r.s.ely serrate; heads in open corymbs._

2. A. corymbsus, Ait. _Stem slender_, somewhat zigzag; _leaves thin, smoothish, coa.r.s.ely and unequally serrate with sharp spreading teeth, taper-pointed_, ovate or ovate-lanceolate, all but the uppermost heart-shaped at the base and on slender naked petioles; _rays 6--9_.--Woodlands; common; especially northward. July, Aug.--Plant 1--2 high, with smaller heads, looser corymbs, rounder and less rigid exterior involucral scales, and thinner leaves than the next; not rough, but sometimes p.u.b.escent.

3. A. macrophllus, L. _Stem stout and rigid_ (2--3 high); _leaves thickish, rough, closely serrate_, abruptly pointed; the lower heart-shaped (4--10' long, 3--6' wide), long-petioled; the upper ovate or oblong, sessile or on margined petioles; heads in ample rigid corymbs; _rays 10--15_ (white or bluish).--Moist woods; common northward, and southward along the mountains. Aug., Sept.--Involucre '

broad; the outer scales rigid, oblong or ovate-oblong, the innermost much larger and thinner.

-- 3. ASTER proper. _Scales imbricated in various degrees, with herbaceous or leaf-like summits, or the outer entirely foliaceous; rays numerous; pappus simple, soft and nearly uniform (coa.r.s.er and more rigid in the first group); achenes flattened._ (All flowering late in summer or in autumn.)

[*] 1. _Scales well imbricated, coriaceous, with short herbaceous mostly obtuse spreading tips; pappus of rigid bristles; stem-leaves all sessile, none heart-shaped or clasping; heads few, or when several corymbose, large and showy._

[+] _Lowest leaves ovate or ovate-oblong, some rounded or subcordate at base._

4. A. Herveyi, Gray. Slightly scabrous, 1--2 high, the summit and peduncles glandular-p.u.b.erulent; leaves roughish, obscurely serrate, the lower ovate on nearly naked petioles, the upper lanceolate; heads loosely corymbose, ' high; involucre nearly hemispherical, the scales obscurely glandular, all erect, with very short or indistinct green tips; rays violet, ' long.--Borders of oak woods, in rather moist soil, E. Ma.s.s, and R. I.; Mt. Desert. An ambiguous species, approaching the last.

[+][+] _Radical leaves all tapering into margined petioles; involucres squarrose (hardly so in n. 8); rootstocks slender._

5. A. spectabilis, Ait. Stems 1--2 high, roughish and glandular-p.u.b.erulent above; leaves oblong-lanceolate, or the lower spatulate-oblong, obscurely serrate or the upper entire; heads few, hemispherical, ' high; _scales glandular-p.u.b.erulent and viscid_; mostly with the _upper half herbaceous and spreading_; rays about 20, bright violet, nearly 1' long.--sandy soil, Ma.s.s. to Del., near the coast, and perhaps southward. Sept.--Nov. One of the handsomest species of the genus.

6. A. surculsus, Michx. Stems 1 high or less, _from long filiform rootstocks; leaves entire_ or nearly so, _rigid_, lanceolate or the upper linear; _heads_ few or solitary, as in the last but generally _smaller_, the _scales hardly glandular_.--Moist ground, coast of N. J., and southward.

7. A. gracilis, Nutt. Rootstocks occasionally tuberous-thickened; stems slender, 1 high; leaves oblong-lanceolate, entire or nearly so, small (1--2' long); heads few or several; involucre top-shaped, 3--4" long, glabrous, not glandular nor viscid, the _coriaceous whitish scales with very short deltoid or ovate tips_; rays 9--12, 3--6" long.--Pine barrens, N. J. to N. C., E. Ky. and Tenn.

8. A. radula, Ait. Stem simple or corymbose at the summit, smooth or spa.r.s.ely hairy, many-leaved (1--3 high); _leaves oblong-lanceolate, pointed, sharply serrate in the middle, very rough both sides and rugose-veined_, closely sessile (2--3' long), nearly equal; _scales of the bell-shaped involucre oblong, appressed, with very short and slightly spreading herbaceous tips_; achenes smooth.--Bogs and low grounds, Del. to Maine and northward, near the coast; also Pocono Mountain, Penn. A dwarf form (var. STRiCTUS, Gray) has oblong- to linear-lanceolate nearly entire leaves, and usually solitary heads; White Mountains, N. H., to Lab. Aug.--Rays light violet. Involucre nearly smooth, except the ciliate margins.

[*] 2. _Involucre and usually the branchlets viscidly or pruinose-glandular, well imbricated or loose; p.u.b.escence not silky; leaves entire (or the lower with few teeth), the cauline all sessile or clasping; rays showy, violet to purple._

[+] _Heads small; involucre not squarrose. Extreme western._

9. A. Fendleri, Gray. Rigid, 1 high or less; leaves firm, linear, 1-nerved, hispid-ciliate, 1' long or mostly much less; heads scattered, 3" high; scales linear-oblong, obtuse, or the inner acute.--Central Kan. (Ellis, _Dr. L. Watson_) and southwestward.

[+][+] _Heads larger; involucral scales spreading, in few or many ranks._

10. A. grandiflrus, L. _Rough with minute hispid hairs_; stems slender, loosely much branched (1--3 high); _leaves very small_ (--1' long), oblong-linear, obtuse, rigid, the uppermost pa.s.sing into scales of the hemispherical squarrose many-ranked involucre; rays bright violet (1'

long); achenes hairy.--Dry open places, Va. and southward.--Heads large and very showy.

11. A. oblongiflius, Nutt. _Minutely glandular-p.u.b.erulent_, much branched above, rigid, paniculate-corymbose (1--2 high); _leaves narrowly oblong or lanceolate_, mucronate-pointed, partly clasping, thickish (1--2' long by 2--5" wide); involucral scales nearly equal, broadly linear, appressed at the base; rays violet-purple; achenes canescent.--Banks of rivers, from Penn. and Va. to Minn. and Kan.--Heads middle-sized or smaller.