Flora Pittsburghensis

Author: Father Pitt

  • Carpetweed (Mollugo verticillata)

    A pretty little flower on a tiny scale, also called “Indian Chickweed” (“Indian” meaning, as it often does in North American plant names, “not really”). Carpetweed is quite variable, especially in the leaves. Note the nearly linear leaves on the specimen above, and the much more elliptical leaves on the one to the right; both grew near the same parking lot by the Monongahela River on the South Side.

    Flowers. White, regular, with five apparent petals (actually sepals), in clusters at leaf axils, with usually one flower per cluster blooming, the rest in bud or gone to seed.

    Leaves. Variable; linear to ovate, entire, dark green; in irregular whorls of three to eight or more.

    Stems. Smooth; prostrate; clambering over other plants or obstacles.

    Gray places the carpetweeds in the “miscellaneous” family Aizoaceae; many botanists now place them in a smaller family of their own, the Molluginaceae. Although he describes it as an “immigrant from farther south,” there is good evidence that Carpetweed is native to our area.

    Gray describes the genus and the species:

    MOLLÙGO L. INDIAN CHICKWEED. Sepals 5, white inside. Stamens hypogynous, 5 and alternate with the sepals, or 3 and alternate with the 3 cells of the ovary. Stigmas 3. Capsule 3-celled, 3-valved, loculicidal, the partitions breaking away from the many-seeded axis. — Low homely annuals, much branched; the stipules obsolete. (An old Latin name for some soft plant.)

    M. verticillàta L. (CARPET WEED.) Prostrate, forming mats; leaves spatulate, clustered in whorls at the joints, where the 1-flowered pedicels form a sort of sessile umbel; stamens usually 3. — Sandy river-banks, roadsides, and cultivated grounds. June-Sept. (Immigrant from farther south.)

  • Horseweed (Conyza canadensis)

    Like most unattractive weeds, this one repays a closer examination. It does not cease to be an unattractive weed when closely examined, but it does have some  interesting and even beautiful parts. Its right elbow has a fascination that few can resist. The plants you see here were blooming beside the Birmingham Bridge on the South Side in late July.

    Flowers. Heads inconspicuous, in panicles; minute white rays, yellow disk; involucre vase-shaped. The heads quickly turn into tiny dandelion-like seed heads, and an inflorescence usually includes some heads still blooming and others gone to seed.

    Leaves. Linear; veins and edges with coarse hairs; upper leaves entire, lower jaggedly toothed or lobed; growing thick on the stem in a spiral.

    Stem. Coarsely hairy, thick, strong, straight; branching at the top into a panicled inflorescence. Height quite variable: some plants more than 7 feet high, others blooming at a foot or less.

    Formerly this species was placed in the genus Erigeron, with the attractive and inoffensive fleabanes. Thus in Gray; but the less attractive members of the genus have since been given a home of their own in Conyza.

    ERIGERON L. FLEABANE. Heads many-flowered, radiate, mostly flat or hemispherical; the narrow rays very numerous, pistillate. Involucral bracts narrow, equal, and little imbricated, never coriaceous, neither foliaceous nor green-tipped. Receptacle flat or convex, naked. Achenes flattened, usually pubescent and 2-nerved; pappus a single row of capillary bristles, with minuter ones intermixed, or with a distinct short outer pappus of little bristles or chaffy scales. — Herbs, with entire or toothed and generally sessile leaves, and solitary or corymbed naked-pedunculate heads. Disk yellow; rays white, pink, or purple. (The ancient name presumably of a Senecio, from er, spring, and geron, an old man, suggested by the hoariness of some vernal species.)

    § 2. CAENÒTUS Nutt. Rays inconspicuous, in several rows, scarcely longer than the simple pappus; annuals.

    E. canadensis L. (HORSE-WEED, BUTTER-WEED.) Bristly-hairy; stem erect, wand-like, 0.1-3 m. high; leaves linear, mostly entire, the radical cut-lobed; heads very numerous and small, cylindrical, panicled. (Leptilon Britton.) — Waste places, etc., a common weed, now widely diffused over the world. July-Oct. —Ligule of the ray-flowers much shorter than the tube, white.

  • Sweet Joe-Pye-Weed (Eupatorium purpureum)

    Now classified under the genus Eutrochium by many botanists; we keep the older classification here for the convenience of Internet searchers.

    There are two common species of Joe-Pye-Weed in our area; the easiest way to identify them is by the leaves, which in this species usually grow in whorls of four, and in E. fistulosum in whorls of six. (Of course, this distinction is not always reliable, but it works most of the time.) Both are spectacular and dignified flowers, which are finally finding their rightful place in perennial gardens as well as our roadsides and meadows. The dusty old-rose color of the flowers is unique, and the straight stems with their perfectly arranged whorls of leaves are some of nature’s most elegant constructions. This plant was one of a patch growing in a wet depression in Schenley Park, along with a larger population of E. fistulosum.

    Britton describes the genus and the species:

    EUPATORIUM L. Erect, perennial herbs, with opposite or verticillate, or sometimes alternate, often punctate leaves, and in our species cymose-paniculate discoid heads of white, blue or purple flowers. Involucre oblong, ovoid, campanulate, or hemispheric, the bracts imbricated in 2-severaI series. Receptacle naked. Corolla regular, its tube slender, its limb 5-lobed or 5-toothed. Anthers obtuse and entire at the base, appendiculate at the apex. Style-branches elongated, flattened, or thickened above, stigmatic at the base. Achenes 5-angled, truncate. Pappus of numerous capillary usually scabrous bristles arranged in I row. [Named for Mithridates Eupator, i.e., of a noble father.] About 475 species, mostly of warm or tropical regions.

    Eupatorium purpureum L. JOE PYE or TRUMPET WEED. (I. F. f. 3615.) Glabrous or sparingly pubescent, 1-3 cm. high. Stem green or purple, usually smooth; leaves thin, verticillate in 3’s-6’s, ovate, oval, or ovate-lanceolate, petioled, acuminate, serrate, sometimes incised, 1-3 dm. long, 3-7 cm. wide; heads numerous; involucre cylindric, its bracts pink, oblong, obtuse, imbricated in 4 or 5 series, the outer shorter; flowers pink or purple, occasionally white. In moist soil. N. B. to Man., Fla. and Tex. Aug.-Sept.

  • Obedient Plant (Physostegia virginiana)

    Also known as False Dragonhead, referring to its resemblance to a snapdragon. The name “Obedient Plant” describes a property that fascinates children, and any adults who are not too jaded to admit to being fascinated. If you push one of the individual flowers to the left or right, it will stay in that position. You can arrange all the flowers artistically on the stem, and they will stay right where you put them. You might almost think the plant had been specially bred by lazy florists. This plant was part of a large patch blooming in late July in a wet depression in Schenley Park.

    Gray describes the genus and the species:

    PHYSOSTEGIA Benth. FALSE DRAGON HEAD. Calyx obscurely 10-nerved, short-tubular or bell-shaped, more or less enlarged and slightly inflated in fruit. Corolla funnel-form, with a much inflated throat, 2-lipped; upper lip erect, nearly entire; the lower 3-parted, spreading, small, its middle lobe larger, broad and rounded, notched. — Smooth perennials, with upright wand-like stems, and sessile lanceolate or oblong mostly serrate leaves. Flowers large and showy, rose or flesh-color variegated with purple, opposite, crowded in simple or panicled terminal leafless spikes. (Name from physa, a bladder, and stege, a covering, in allusion to the calyx, which is at length somewhat inflated.)

    • Stem conspicuously leafy up to the inflorescence.

    P. virginiàna (L.) Benth. Stem 0.6-1.3 m. high, terminated by asimple virgate spike or several panicled spikes ; leaves thickish, mostly sharply serrate; calyx tubular-campanulate, its teeth half the length of the tube, acuminate, at length acerosetipped; corolla 1.8-2.3 cm. long. — Wet grounds, from w. Que. westw. and southw.; frequently escaped from cultivation in e. N. E. June-Sept.

    –

    In her Guide to the Wild Flowers (1899), Alice Lounsberry gives us this description:

    Flowers: growing closely in a dense spike on axillary flower-stalks. Calyx ; bell-shaped, of five-toothed sepals. Corolla: funnel-form; inflated; two-lipped, the upper lip arched and broad; the lower one of three spreading lobes, the centre lobe pale and dotted with a deep colour. Stamens: four; in pairs. Pistil: one; style two-lobed. Leaves: opposite; lanceolate; serrated. Stem: square; one to four feet high; slightly branched.

    When a little fish comes to the surface of the water and opens his mouth his expression is not unlike that of these flowers. They have, however, none of the darting, evasive tendencies of the fish. The flower is most docile. Strangely enough, it appears to be without any elasticity, and will remain in exactly the position in which it is placed for an indefinite time. From this characteristic the plant quite carries off the palm of obedience among the flowers.

  • Spearmint (Mentha spicata)

    You could look at spearmint as an invasive wed, but it gives us so much in return for the space it takes that it’s a hard weed to resent. Spearmint spreads mainly by runners, forming large, dense patches. Its scent and flavor are recognizable at once. It blooms with pleasant spikes of little white flowers that were attracting little green flies when this picture was taken. This plant was part of a large patch blooming in late July in Beechview.

    Flowers. In terminal spikes;  white with pink lines especially on upper lip; in whorls of a dozen or more; stamens twice the length of the corolla.

    Leaves. Sessile; ovate-lanceolate, deeply veined, looking wrinkled; toothed, about 2 and a half or 3 times as long as broad.

    Stems. Square, about 3 feet tall, wiry, often branching near the flower spike. Long underground or at-surface stems from which upright stems rise at rooting joints.

    The whole plant is, of course, strongly aromatic, and its aroma and flavor are its most identifiable characteristics.

    Gray describes the genus and the species:

    MENTHA [Tourn.] L. MINT. Calyx Ьеll-shaped or tubular, the 5 teeth equal or nearly so. Corolla with a short included tube, the upper lobe slightly broader, entire or notched. Stamens 4, equal, erect, distant. — Odorous perennial herbs ; the small flowers mostly in close clusters, forming axillary capitate whorls, sometimes approximated in interrupted spikes, produced in summer, of two sorts as to the fertility of the stamens in most species. Corolla pale purple or whitish. Species mostly adventive or naturalized from Europe, with many hybrids. (Minthe of Theophrastus, from a Nymph of that name, fabled to have been changed Into Mint by Proserpine.)

    Spikes narrow and leafless, densely crowded; leaves sessile or nearly so.

    Spikes not canescent.

    M. spicata L. (SPEARMINT.) Nearly smooth; leaves oblong-or ovate-lanceolate, unequally serrate, sometimes short-petioled; bracts linear-lanceolate and subulate, conspicuous. (M. viridis L.) — Wet places, common. (Nat. from Eu.)