Something odd is happening with this species around here. It used to be fairly rare, but over the past few years it seems to have become a common little weed. This is a miniature version of the common Forget-Me-Not (M. scorpioides), very similar except for the size. It’s normally found near streams, but in Pittsburgh it likes the edge of a sidewalk just as well, especially if it’s a moist area like a drainpipe outflow.
Gray describes the genus and the species:
MYOSOTIS [Rupp.] L. SCORPION-GRASS. FORGET-ME-NOT Corolla-tube about the length of the 6-toothed or 5-cleft calyx, the throat with 5 small and blunt arching appendages opposite the rounded lobes; the latter convolute in the bud! Stamens included, on very short filaments. Nutlets compressed. Low and mostly soft-hairy herbs, with entire leaves, those of the stem sessile, and with small flowers in naked racemes, which are entirely bractless, or occasionally with small leaves next the base, prolonged and straightened in fruit. (Name composed of myos, mouse, and os, ear, from the short and soft leaves in some species.)
M. laxa Lehm. Perennial from filiform subterranean shoots; stems very slender, decumbent; pubescence all appressed; leaves lanceolate-oblong or somewhat spatulate; calyx-lobes as long as the tube; limb of corolla rarely 5 mm. broad, paler blue. In water and wet ground, Nfd. to Ont., and southw. May-Aug. (Eu.)
Purslane is all over the world, and whether it came to America with Europeans or was native here is an open question. We most often find it in city neighborhoods; it especially likes brick sidewalks. These unusually lush specimens were growing in the little parklet at the end of the Birmingham Bridge on the South Side.
We last mentioned Purslane in 2012, so we repeat what we said then:
This tiny prostrate weed is a close relative of the colorful Moss Roses we grow in gardens—the thick, fleshy red stems and succulent leaves show the relationship clearly. The little yellow flowers open only in the morning, and only in bright sunlight. Purslanes can grow almost anywhere they get a foothold, and can survive being pulled up and thrown away to root elsewhere. In the city they are very common crack-in-the-sidewalk weeds.
Gray describes the genus and the species:
PORTULACA [Tourn.] L. PURSLANE. Calyx 2-cleft; the tube cohering with the ovary below. Petals 5, rarely 6, inserted on the calyx with the 7-20 stamens, fugacious. Style mostly 3-8-parted. Pod 1-celled, globular, many-seeded, opening transversely, the upper part (with the upper part of the calyx) separating as a lid. — Fleshy annuals, with mostly scattered leaves. (An old Latin name, of unknown meaning.)
P. olerácea L. (COMMON P.) Prostrate, very smooth; leaves obovate or wedge-form; flowers sessile (opening only in sunny mornings); sepals keeled; petals pale yellow; stamens 7-12; style deeply 5-6-parted; flower-bud flat and acute. — Cultivated and waste grounds; common.—Seemingly indigenous westw. and southwestw. (Nat. from Eu.)
Also called Mock Strawberry. Ubiquitous in lawns, this little weed bears beautiful fruits that look delicious but taste like nothing. Father Pitt has taste-tested these fruits for you, so you will not have to bother. The flavor is not unpleasant, but not pleasant either. If you were starving and came on a lawn full of Indian Strawberries, you would not hesitate to eat more after you had tasted the first; but if you were not starving, you would find no reason to eat more after you had tasted the first.
In older references this species is Duchesnea indica; modern genetic research shows that it belongs in the genus Potentilla with the Cinquefoils. The common name “Indian” refers not to American Indians but to India, which is in the native range of these plants. Indian Strawberries came here as ornamentals, and they certainly do make an attractive groundcover. In our lawns they are harmless unless you are a grass fundamentalist.
Gray counts this species as Duchesnea; since the genus Duchesnea is now included in Potentilla, we give his description of that genus as well.
POTENTÍLLA L. CINQEFOIL. FIVE-FINGER. Calyx flat, deeply 5-cleft, with as many bractlets at the sinuses, thus appearing 10-cleft. Petals 5, usually roundish. Stamens many. Achenes many, collected in a head on the dry mostly pubescent or hairy receptacle; styles lateral or terminal, deciduous. Radicle superior. — Herbs, or rarely shrubs, with compound leaves, and solitary or cymose flowers; their parts rarely in fours. (Name a diminutive from potens, powerful, originally applied to P. Anserina, from its once reputed medicinal powers.)
DUCHESNEA Sin. INDIAN STRAWBERRY. Calyx 5-parted, the lobes alternating with much larger foliaceous spreading 3-toothed appendages. Petals 5, yellow. Receptacle in fruit spongy but not juicy. Flowers otherwise as in Fragaria. Perennial herb with leafy runners and 3-foliolate leaves similar to those of the true strawberries. (Dedicated to Antoine Nicolas Duchesne, an early monographer of Fragaria.)
D. indica (Andr.) Focke. Fruit red, insipid. (Fragaria Andr.) Waste ground, grassy places, etc., s. N. Y. and e. Pa. to Fla., Ark., and Mo. (Introd. from Eurasia.)
Two close-up pictures of the same plant growing beside a street in Beechview. The deep violet, or “rich purplish-blue” as Gray describes it, is very hard to capture with a digital camera, which always seems to want to make the petals much bluer than they are; old Pa Pitt worked hard in the GIMP to match the color of the living flower.
We have seen Spiderworts before (ten years ago!), and we’ll repeat what we said then:
A native plant that is perhaps even more common in gardens than in the wild; the purple to blue flowers with three equal petals and the linear, almost grasslike leaves are distinctive. The closest common relatives in our area, the Dayflowers, have three unequal petals and much shorter leaves. Like Dayflowers, these bloom in the morning and disappear by the middle of the afternoon.
Gray describes the genus and the species:
TRADESCÁNTIA [Rupp.] L. SPIDERWORT. Flowers regular. Sepals herbaceous. Petals all alike, ovate, sessile. Stamens all fertile; filaments bearded. Capsule 2-4-celled, the cells 1-2-seeded — Perennials. Stems mucilaginous, mostly upright, nearly simple, leafy. Leaves keeled. Flowers ephemeral, in umbeled clusters, axillary and terminal, produced through the summer; floral leaves nearly like the others. (Named for the elder Tradescant, gardener to Charles the First of England.)
T. virginiàna L. Green; leaves flat, linear or lance-linear, the upper moге or less pubescent; bracts leaf-like, elongated, usually ascending; pedicels and sepals villous, the latter about 1.6 cm. long; petals rich purplish-blue, 1.6-2 cm. long — Alluvial soil, Ct. to Pa. and S. C.: also introd. northw.
Daisies are sometimes weedy invaders, but it is almost impossible to hate them. They do sometimes form dense patches and crowd out native plants; but large patches like these are relatively infrequent, and they do not seem to pose a serious danger to our ecosystem.
There is no reason not to repeat what we said ten years ago:
This is the most universally beloved of all wild flowers, the focus of countless childhood traditions and the very image of “flower” in the popular imagination. It may be derided as a pernicious weed by agricultural and environmental authorities, but the ordinary citizen will never be persuaded to hate it.
Daisies like these were formerly kept in the genus Chrysanthemum, but have been removed by bored botanists to the genus Leucanthemum “because they are not aromatic and their leaves lack grayish-white hairs,” according to the Wikipedia article on the genus. (The genus “Leucanthemum” was apparently named by Lamarck, whose discredited theory of inheritance of acquired characteristics still haunts high-school biology classes.) Because of this new sorting of the genera, we leave Gray and give the description of the genus and species from the Flora of North America at efloras.org:
Perennials, (10–)40–130(–200+) cm (rhizomatous, roots usually red-tipped). Stems usually 1, erect, simple or branched, glabrous or hairy (hairs basifixed). Leaves mostly basal or basal and cauline; petiolate or sessile; blades obovate to lanceolate or linear, often 1[–2+]-pinnately lobed or toothed, ultimate margins dentate or entire, faces glabrous or sparsely hairy. Heads usually radiate, rarely discoid, borne singly or in 2s or 3s. Involucres hemispheric or broader, 12–35+ mm diam. Phyllaries persistent, 35–60+ in 3–4+ series, distinct, ovate or lance-ovate to oblanceolate, unequal, margins and apices (colorless or pale to dark brown) scarious (tips not notably dilated; abaxial faces glabrous or sparsely hairy). Receptacles convex, epaleate. Ray florets usually 13–34+, rarely 0, pistillate, fertile; corollas white (drying pinkish), laminae ovate to linear. Disc florets 120–200+, bisexual, fertile; corollas yellow, tubes ± cylindric (proximally swollen, becoming spongy in fruit), throats campanulate, lobes 5, deltate (without resin sacs). Cypselae ± columnar to obovoid, ribs ± 10, faces glabrous (pericarps with myxogenic cells on ribs and resin sacs between ribs; embryo sac development monosporic); pappi 0 (wall tissue of ray cypselae sometimes produced as coronas or auricles on some cypselae). x = 9.
Species 20–40+ (3 in the flora): introduced; mostly temperate Europe (some widely cultivated and sparingly adventive).
The three leucanthemums recognized here are weakly distinct and are sometimes included (with a dozen or more others) in a single, polymorphic Leucanthemum vulgare.
SELECTED REFERENCE
Vogt, R. 1991. Die Gattung Leucanthemum (Compositae–Anthemideae) auf der Iberischen Halbinsel. Ruizia 10: 1–261.
Chrysanthemum leucanthemum Linnaeus, Sp. Pl. 2: 888. 1753; C. leucanthemum var. pinnatifidum Lecoq & Lamotte
Perennials, 10–30(–100+) cm. Stems simple or distally branched. Basal leaves: petioles 10–30(–120) mm, expanding into obovate to spatulate blades 12–35(–50+) × 8–20(–30) mm, margins usually pinnately lobed (lobes 3–7+) and/or irregularly toothed. Cauline leaves petiolate or sessile; blades oblanceolate or spatulate to lanceolate or linear, 30–80+ × 2–15+ mm, margins of mid-stem leaves usually irregularly toothed proximally and distally.Involucres 12–20+ mm diam. Phyllaries (the larger) 2–3 mm wide. Ray florets usually 13–34+, rarely 0; laminae 12–20(–35+) mm. Ray cypselae 1.5–2.5 mm, apices usually coronate or auriculate. 2n = 18, 36, 54, 72, 90.
Some botanists (e.g., W. J. Cody 1996) have treated Leucanthemum ircutianum de Candolle, with blades of mid and distal cauline leaves oblong to oblong-lanceolate and not ± pinnate at bases, as distinct from L. vulgare.
