Family: Polemoniaceae
Phlox image
David Lee  

Key to Wisconsin Phlox

Author: Jeff Rose

    • 1a.Plants matted or tufted; corolla lobes bifid; pistil as long as the corolla tube 2

    • 1b.Plants caulescent (although some species are stoloniferous); corolla lobes rounded or apiculate; pistil as long as or much shorter than the corolla tube 3

    • 2a.Hairs glandular; leaves 1.0–4.0 cm long, longer on sterile shoots, pubescent on the margin and both surfaces of the lamina; notch of the corolla lobes 3–6 mm deep P. bifida

    • 2b.Hairs eglandular; leaves 0.8–2 cm long, similar in length on fertile and sterile shoots glabrous or if pubescent, only so on the margin; notch of the corolla lobes 0.5–2 mm deep P. subulata

    • 3a.Stem, leaves, calyx, and corolla tube glabrous P. glaberrima

    • 3b.Upper stem and usually also leaves pubescent (at least on the margin); calyx pubescent; corolla tube glabrous or pubescent 4

    • 4a.Cauline leaves ovate, with clearly anasmotising lateral veins; pistil as long as the corolla tube P. paniculata

    • 4b.Cauline leaves ovate to linear, lateral veins indistinct; pistil much shorter than the corolla tube 5

    • 5a.Plants stoloniferous; cauline leaves ovate; calyx hairs glandular; corollas lavender blue to white, sometimes with a whitish “eye”, tube glabrous P. divaricata

    • 5b.Plants not stoloniferous; cauline leaves linear or narrowly lanceolate; calyx hairs eglandular (except in a rare subspecies); corollas pink or white, usually with distinctively darker nectar guides, tube pubescent P. pilosa

A common and familiar genus, Phlox is often confused with members of Brassicaceae or Caryophyllaceae (especially Hesperis, of the former family). However, the sympetalous corolla immediately distinguishes Phlox from both. Phlox maculata L. is known from Illinois, Iowa, and Minnesota but has not yet been reported from Wisconsin. It is to be expected in the state and appears to be increasingly added in prairie plantings. It differs from all species in having a spotted stem, glabrous leaves without obvious lateral veins, an elongate paniculiform inflorescence with short eglandular hairs on the axis and a glabrous corolla tube.