Part 42

Smooth, forming depressed tufts on slender, creeping rootstocks. Leaves chiefly at the root, 1—2 inches long including the petioles, obovate to spatulate, entire, repand dentate or lyrate, commonly equalling the clustered stems. Heads few-flowered, nearly ½ an inch high, narrowly cylindric, ⅛ of an inch in diameter; flowers bright yellow, spreading ¼ of an inch across.

A small alpine plant growing among loose stones and on the moraines and on slides and summits throughout the Rockies; flowering in midsummer.

Smooth, many-stemmed from a perennial tap-root, 6—12 inches high, diffusely branched. Leaves entire or nearly so; root leaves spatulate; stem-leaves from lanceolate to linear. Heads numerous, narrowly cylindric, ¼—⅓ of an inch high, the pale yellow flowers little more than ⅓ of an inch across.

In gravel beds along the rivers and larger streams throughout the Rockies; flowering during July.

Stem rather slender, smooth or puberulent, sometimes rough hairy below, leafy, simple, 1—2½ feet high. Leaves lanceolate or the lowest spatulate, entire, denticulate or sometimes laciniate-dentate, acute or acuminate, 1—3 inches long, smooth above, usually hairy beneath with the margins fringed with hairs. Heads of flowers nearly an inch broad, umbellate, bright yellow.

On banks and near rivers in the Rockies; flowering in July.

Hairy throughout with long, soft hairs; 1—2 feet high. Leaves lanceolate or spatulate-lanceolate, 3—6 inches long. Flowers in an irregular branching panicle. Head ½ an inch high; involucre with copious long bristly hairs; flowers bright yellow, ½ an inch or more broad.

On banks and stony open ground throughout the region flowering during July.

Growing in tufts, pale green. Leaves nearly all in clusters at the root, obovate to oblong-spatulate, 1—3 inches long, attenuate into petioles, entire or repand denticulate. Stems 8—18 inches high, brownish-hairy above, bearing few or several heads of flowers near the top; involucres about ⅓ of an inch high, usually blackish-hairy at the base; flowers bright yellow in heads ¼ of an inch or less broad.

In dry open or shaded places at the higher elevations throughout the region, growing in sand; flowering in July.

Loosely branching and hairy with long hairs; 1—3 feet high. Leaves oblong, thin, 2—6 inches long. Involucres narrow-campanulate, ⅓ to nearly ½ an inch high; flowers white, ¼ of an inch across or more; several in a compound cyme.

On sandy banks and open mountain sides, frequent throughout the region at the lower elevations; flowering during June and July.

CARDUACEÆ

Thistle Family

Herbs with watery or resinous sap and alternate, opposite or basal leaves; flowers perfect, pistillate or neutral; borne on a common receptacle forming heads, surrounded by an involucre of few to many bracts in one or more series; calyx tube attached to the top of the ovary, the limb (pappus) of bristles, awns, teeth, scales, crown-like or wanting; corolla tubular, usually 5-lobed or -cleft, the marginal flowers frequently expanded into a ligule (ray); when the ray flowers are absent the head is said to be discoid, when present, radiate; the tubular flowers form the disc. The largest of all the families of flowering plants comprising about 760 genera and not less than 10,000 species, represented in the region by the following:

Anthers not tailed at the base; heads rayed or rayless. Style branches of the perfect flowers flattened, with terminal appendages. Rays yellow or sometimes wanting. Pappus double, the outer very short. =Chrysopsis.= Pappus simple; panicle compact. =Solidago.= Rays white, purple, or blue, rarely wanting. Involucral bracts in 1—2 series, narrow; rays usually narrow and numerous. =Erigeron.= Involucral bracts in 2—5 series; rays broader and less numerous. Scales of the involucre dry, papery and appressed. =Eucephalus.= Scales of the involucre more or less herbaceous, and spreading. =Aster.= Style branches of the perfect flowers straight edged or with hairy tips. Involucre not scarious. Pappus never capillary; receptacle chaffy or bristly. Receptacle conic, chaffy; pappus none. =Rudbeckia.= Receptacle flat, chaffy; tall herbs; pappus 2 scales. =Helianthus.= Receptacle bristly; pappus a crown of scales. =Gaillardia.= Pappus capillary. Leaves all or mostly opposite. =Arnica.= Leaves alternate. Flowers white or pinkish; leaves large. =Petasites.= Flowers yellow, leaves small. =Senecio.= Involucre scarious. Receptacle chaffy; rays short. =Achillea.= Receptacle naked; rays conspicuous. =Chrysanthemum.= Receptacle naked; rays none. =Artemisia.= Anthers with tails at the base; heads without rays. Receptacle not bristly; corolla not deeply cleft. Pappus hair-like in pistillate flowers; club shaped in staminate. =Antennaria.= Pappus of all the flowers similar. =Anaphalis.= Receptacle long bristly; corolla deeply cleft. Leaves and usually the involucral bracts prickly =Carduus.= Leaves and involucral bracts not prickly. =Saussurea.=

Stems numerous from a woody rootstock, rough-hairy throughout, spreading, 6—12 inches long. Leaves spatulate to oblong, entire, spreading, ¾—1½ inches long, obtuse at the apex, narrowed at the base, often into petioles half as long as the blade or more. Heads very numerous, about ½ an inch broad; involucre less than ½ an inch high, its bracts lanceolate, rough-hairy; ray flowers bright yellow, ¼ of an inch or more long.

In dry soil through the lower valleys throughout the Rockies; flowering in midsummer.

Stems smooth or somewhat hairy above, slender, 6—15 inches high. Leaves firm, smooth or nearly so, the basal and lower ones spatulate or oblanceolate, entire or sparingly serrate, obtuse, finely reticulate-veined, 3—5 inches long, the upper smaller and narrower, entire. Heads about ⅓ of an inch high, usually few in a rather compact terminal cyme; bracts of the involucre thin, linear-lanceolate, acute, smooth; rays 8—15, large.

On open hillsides throughout the region; flowering in July.

Stems clustered at the summit of a strong, perpendicular root, stout, decumbent, 6—18 inches high, usually dark red and sparsely hairy. Leaves spatulate-obovate to oblanceolate, obtuse or acutish, more or less distinctly serrate toward the summit, upper cauline leaves similar but few and reduced, all rough on the margins. Heads large in a thyrsoid panicle; bracts of the involucre glandular-viscid, linear, obtuse, of firm texture, nerved; rays large.

Smooth, rather slender, 3—5 feet high. Leaves firm or thick, those of the stem linear-lanceolate and sessile, acuminate at the apex, narrowed at the base, 2—4 inches long, rough-margined, triple-nerved, entire or sparingly serrate with low sharp teeth, the basal and lowest ones longer, spatulate and petioled. Heads ⅛—¼ of an inch high on one side of the spreading or recurving branches of the short panicle; bracts of the involucre oblong, greenish-tipped, obtuse; rays 6—13, short.

In dry soil on the edges of woodland at the lower altitudes throughout the Rockies; flowering in August.

Stout, rough-hairy or slightly so, 2—8 feet high. Leaves lanceolate, triple-nerved, acute at each end, the lower ones sharply serrate and petioled, 3—6 inches long, ⅓—1 inch wide, the upper smaller, entire. Heads small, ⅛ of an inch or less high, very numerous on one side of the spreading or recurved branches of the usually large and dense panicle; involucral bracts linear, obtuse or acutish; rays 9—15 small.

In open usually dry soil at the lower altitudes throughout the Rockies; flowering during July and August.

b Erigeron acris L. Blue Fleabane.

c Saussurea densa Hook. Saussurea. (⅗ Nat.)]

Stems 1—6 inches high, several from the same root. Leaves few, the basal spatulate or oblanceolate, 1—2 inches long; stem leaves linear and few. Heads ⅓ of an inch in diameter, solitary; involucre usually rough-hairy as well as woolly, bracts linear acute, rather close, rays ¼—⅓ of an inch long, white, very numerous.