Flora Pittsburghensis

Category: Compositae

  • Salsify (Tragopogon dubius)

    Tragopogon dubius
    Photographed May 23.

    Also listed as T. major, and there are various other common names, including goat’s-beard (of which the genus name “Tragopogon” is a literal translation into Greek) and oyster-flower. Two similar species of yellow Salsify grow in our area; this seems to be more common and prefers gravely waste places. The plants shown here were growing among the litter in a gravel roadside in Banksville. Fernald’s revised edition of Gray gives us a feature to look for to distinguish this species: “peduncle upwardly enlarged below the head.” The “peduncle” is the stem that carries the flower; note the way it swells toward the developing seedhead in the picture below.

    Closed seedhead of Tragopogon dubius

    The leaves are grasslike at the base of the plant, a bit broader along the stem; the flowers are followed by huge-dandelion-like seedheads nearly as big as a closed fist.

    Salsify

  • Philadelphia Fleabane (Erigeron philadelphicus)

    Erigeron philadelphicus
    Photographed May 17.

    Philadelphia Fleabane is found in many of the same places as Common or Daisy Fleabane (Erigeron annuus), and the two can be hard to tell apart at first glance. Philadelphia Fleabane has even more rays—usually more than a hundred per flower head—giving the heads a shaggy appearance. As we see above, Philadelphia Fleabane is also more likely to show a pink tinge or occasionally a strong pink color, but that is not a reliable indicator, since many Philadelphia Fleabanes are pure white. These plants were growing in a large patch along a street in Beechview.

    Philadelphia Fleabane close up

    This common weed can tolerate some shade, so we often see large patches of it in lightly shaded overgrown areas near parking lots or roads.

    Philadelphia Fleabane

    For a description of the species, see the Erigeron philadelphicus reference page

    Erigeron philadelphicus, habitus

    In the picture above, note how the heads in bud are nodding—hanging down—before they open.

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  • Spanish Needles (Bidens bipinnata)

    Bidens bipinnata flower head

    The flower heads look like tiny marigolds, but the seeds are what you are most likely to notice. They catch in your clothes (or in an animal’s fur, but they almost seem designed for human-made fabrics) and take a ride to some other location that, with any luck, will be hospitable to Bidens bipinnata. These plants were growing against a fence in Beechview.

    Seeds of Bidens bipinnata
    Photographed September 28 with a Konica Minolta DiMAGE Z6.

    For a description of the species, see the Bidens bipinnata reference page.

  • Blue Wood Aster (Symphyotrichum cordifolium)

    Symphyotrichum cordifolium
    Photographed September 26.

    Known as Aster cordifolius in most botanical literature, but the North American Asters have been separated into the genus Symphyotrichum by botanists who enjoy the challenge of a pentasyllabic Greek term. Identifying Asters is hard, because there are many species and they hybridize. This, however, is a very common one. Its generous clusters of small closely spaced blue flower heads decorate our roadsides and brighten woodland trails. The lower leaves are lanceolate with heart-shaped bases, giving the species its name and one of its other common names, “Heartleaf Aster.”

    These plants were photographed in Bird Park, Mount Lebanon, and in the Kane Woods Nature Area, Scott Township.

    Blue Wood Aster
    Heartleaf Aster
    Photographed September 25.
    Aster cordifolius
    Symphyotrichum cordifolium
    Blue Wood Aster
    Aster cordifolius

  • Chicory (Cichorium intybus)

    Cichorium intybus

    These cheerful sky-blue flowers are everywhere from summer into fall, but they are no less delightful for being common. These were blooming along the Montour Trail in Moon Township.

    Chicory
    Photographed September 24 with a Canon PowerShot SX150 IS.

    For a description of the species, see the Cichorium intybus reference page.