Flowers in late spring, May to July, depending upon elevation (Locklear 2011).
The low growing species of
Phlox are taxonomically challenging to identify. A technical botanical key and examination of herbarium specimens should be used to positively identify species. Below are diagnostic characteristics for
Phlox Kelseyi and
some of its look-alikes:
Kelsey’s Phlox -
Phlox kelseyi* Plants: Glabrous (without hairs) to pubescent or glandular-pubescent. Tendency to form spreading clumps.
* Leaves: Succulent, more or less; pale green. The portion of the leaf margin that is ciliate is highly variable.
* Flowers: White, singular on stem.
* Calyx: Glabrate to glandular-villous, often ciliate. Glabrous to pubescent or glandular-pubescent. Flat intercostal membranes.
* Style: 4.0-7.5 mm long.
* Habitat: Wetlands, moist meadows, vernally moist alkaline meadows, alkaline flats, or near hot springs in valleys to montane zones of Montana.
* Montana’s Distribution: West-central and Carbon County.
Missoula Phlox -
Phlox missoulensis, SOC
* Plants: Pubescent with gland-tipped hairs – at least on the calyx. Tendency to form alpine-like cushions.
* Leaves: Not succulent; firm to rigid; dark green. Greater than half of the leaf margin is ciliate.
* Flowers: White to blue, singular on stem.
* Calyx: Intercostal membrane is
narrower than the thickened herbaceous portion of the calyx lobe base.
* Style: 4.0-7.5 mm long.
* Habitat: Upland habitats; stoney soil on ridges in valleys.
* Global Distribution: Missoula County (narrow endemic).
Many-flowered Phlox -
Phlox multiflora* Stems: lacks hairs (glabrous) below, villous and glandular above.
* Leaves: Not succulent, but pliable. Linear in shape
and minutely scabrous – sometimes sparsely villous.
* Flowers: Generally white or pale bluish, 1-3 per stem.
* Calyx: Tube glabrous or occasionally pubescent. Flat intercostal membranes.
* Habitat: Sagebrush steppe, grasslands, open forests in the montane to lower alpine zones.
* Montana’s Distribution: Southwest, South-central, and Flathead County.
Spreading Phlox -
Phlox diffusa* Leaves: Not succulent, but firm. Linear in shape, glabrous or weakly scaberulous, ciliate, and 5-15 mm long.
* Flowers: Pink, blue-purple, or white, 1 per stem.
* Calyx: villous, especially on tube, or very rarely eglandular-pubescent or glabrous. 5-9 mm long. Flat intercostal membranes.
* Habitat: Stony, non-calcareous fellfields, open slopes, forest openings, and rock outcrops in the upper montane to alpine zones.
TAXONOMY & NOMENCLATUREMontana’s plants of
Phlox kelseyi Britton belong to variety
kelseyi. The Type specimen, which is the base for the species’ description, was collected near Helena, Montana in May 1988 by Francis Duncan Kelsey (1849-1905) (
image NYBG).
For
Phlox kelseyi, Wherry (1955) recognized two varieties,
kelseyi and
salina and Cronquist (1959) recognized a third variety,
missoulensis. Montana has varieties
kelseyi and
missoulensis while Nevada has variety
salina (Wherry 1955; Cronquist 1959; Locklear 2011). Campbell (1992) examined the biosystematics of
Phlox kelseyi varieties
missoulensis,
kelseyi, and
salina and concluded they should be recognized as subspecies.
Phlox kelseyi var/ssp
missoulensis has been elevated to species recognition as
P. missoulensis.
Across the global range, Kelsey’s Phlox is found in a variety of wetland communities, such as along the margins and on hummocks in fens, on benches above streams and fens, saline flats, and in Nevada is associated with geothermal areas.
In Montana, Kelsey’s Phlox grows in wetlands in the zones from valley to montane (Lesica et al. 2022). Plants grows in alkaline wet meadows and fens on hummocks and in association with shrubland and the dwarf-carr community type, and other wetland habitats (Lesica et al. 2022; Locklear 2009).
