Following are several characteristics that help separate S. foliaceum from S. spathulatum: 

1) S. foliaceum phyllaries tend to be broader, longer, and rounded at the apex.  

2) S. foliaceum middle stem leaves are less than seven times as long as wide. Overall the leaves of this plant tend to be elliptic to lance shaped.  They are generally shorter and wider than S. spathulatum which tends to have linear to lance-shaped leaves.

S. spathulatum middle stem leaves are more than seven times as long as wide.

3) S. foliaceum basal leaves are usually withered at flowering time (anthesis); S. spathulatum basal leaves are usually present at flowering time.

   Flower color in both species is highly variable through all shades of blue/purple/pink/white.

   The Flora of North America notes that "Symphyotrichum foliaceum is extremely variable" and "Symphyotrichum spathulatum is a variable species".  The Flora does not specifically mention the length to width ratio of the middle stem leaves of the two species, but it gives measurements that support this distinction. (See S. foliaceum and S. spathulatum.)

   The name "foliaceum" refers to the foliage-like phyllaries and bracts subtending the phyllaries of Symphyotrichum foliaceum.  "Spathulatum" is Greek for "like a spatula" and the name refers to the leaf shape.  But each species is so highly variable in these two characteristics, that the specific epithets are only broadly applicable.

    In 1995 Asteraceae expert Guy Nesom proposed, on the basis of extensive analysis, moving many members of the genus "Aster" (including the two shown on this page) to the genus "Symphyotrichum" and that genus name quickly became accepted. 

    "Sym phyo trichum" is Greek for "with growing hairs" or "with hairs coming together" and perhaps refers to the long lines of hairs sometimes seen on these plants.

Also see Symphyotrichum ascendens
and
Symphyotrichum ericoides, Symphyotrichum falcatum, & Symphyotrichum lanceolatum

Montane, subalpine, alpine. Woodlands, wetlands, openings, disturbed. Summer, fall.
Upper Calico Trail, July 22, 2015.

This variety of Symphyotrichum foliaceum is distinguished by its shorter stature (to 8 inches tall); fine, continuous line of stem hairs; and rounded, purple-edged phyllaries in several rows. The closed, overlapping ray flowers are dark purple, but they will be much lighter when they open.

Symphyotrichum foliaceum variety apricum tends to grow at higher elevations than the two varieties shown below.

Foothills, montane. Woodlands, openings. Summer, fall.
Upper Calico Trail, August 15, 2013.

Foothills, montane. Woodlands, openings. Summer, fall.
Navajo Lake Trail, August 30, 2007.

Symphyotrichum foliaceum varieties grow from five to twenty-eight inches tall and are commonly found in small colonies that arise from spreading roots. Basal leaves are often withered at flowering time and stem leaves are broad, prominently veined, and reduced in size and number upwards.  Hairs are often in one to few straight lines on the stem below the leaf base (see above and below).  

Linnaeus named the Aster genus in 1753 and John Lindley named this species in 1836 from a specimen collected by Fischer in Unalaschka.  In 1995 Guy Nesom proposed moving many members of the Aster genus to Symphyotrichum and that proposal is now accepted by most botanists. The Symphyotrichum genus was named by Christian Nees in 1832. 

Trichomes are hairs and "symphy" means "coming together".  So "Symphyotrichum" refers to hairs growing together, probably referring to the line of hairs common on this species. S. foliaceum gets its name from its (usually) long and broad, leaf-like (foliage-like) outer phyllaries and its commonly very leaf-like bracts subtending the involucre.

Montane, subalpine. Woodlands, openings. Summer, fall.
Navajo Lake Trail, August 30, 2007.

Outer phyllaries are longer than the inner on this variety of S. foliaceum.

Montane, subalpine. Woodlands, openings. Summer, fall.
Foothills, montane. Woodlands, openings. Summer, fall.
Upper Calico Trail, August 15, 2013 and Mesa Verde National Park, September 8, 2007.

A major factor separating Symphyotrichum species and varieties is the color and size of their phyllaries, but the differences are often difficult to discern and characteristics of the varieties overlap. The top photograph at left shows variety parryi's inner and outer phyllaries about the same length; the bottom photograph shows variety canbyi's longer outer phyllaries.

See below for the phyllaries most typical of S. spathulatum.

Foothills, montane. Fields, openings, disturbed areas. Summer, fall.
Upper Calico Trail, August 15, 2013.

The photograph at left shows that although there are hairs all over the stem of this S. foliaceum plant, most hairs are massed in a straight, narrow, vertical line and that they are in line with the edge of the leaf base (near top of the photograph). You can see that the leaf base clasps the stem and the hairs reach to the base.

Weber indicates that such hair lines are a hallmark of Symphyotrichum lanceolatum and the leaf line separates this species from S. foliaceum and S. spathulatum; other botanical experts disagree. The stem at left supported the flower shown in the S. foliaceum var. parryi photograph directly above.

Foothills, montane. Meadows, openings, streamsides. Summer, fall.
Above: Grand Mesa, July 13, 2017.
Left: Wildcat Trail, August 28, 2007.

Symphyotrichum spathulatum occurs in colonies that arise from strong, spreading rhizomes. The species varies widely in height and leaf dimensions, growing from 20-80 cm tall with leaves from 50–150 mm long and 3–15 mm wide. This and several other Symphyotrichum species frequently hybridize and thus plant characteristics vary widely and, in fact, exact species identification is often problematic.

The lush plants shown immediately above were growing at 10,500 feet in a cool, moist meadow crowded with many other species in robust condition. The less developed plants at left and below were growing at 8,400 feet in a much warmer, drier forest meadow environment. 

Symphyotrichum spathulatum leaf hairs (either upright or arched) are only on the leaf edges. Stems are glabrous or sparsely hairy, with hairs sometimes occurring below the involucre and in lines along the stem.

Foothills, montane. Meadows, openings, streamsides. Summer, fall.
Wildcat Trail, August 28, 2007.

Look carefully at the phyllaries of Symphyotrichum spathulatum and you will notice that they are dark green at the tips and much lighter green, even almost white near the center bottom.

Phyllaries are in several over-lapping rows and the outer phyllaries are typically shorter, but may all be about the same length.

If you compare these phyllaries with those of S. foliaceum (above) you will see that S. spathulatum phyllaries are narrow, variable in length, and the tip is acute; the phyllaries of S. foliaceum are most often broad, relatively equal in length (outer phyllaries are often even longer that inner ones), and the tip is often rounded but may be acute or obtuse, sometimes (according to A Utah Flora) even with a finely drawn out tip.

Unfortunately, however, the phyllary characteristics described above for one species sometimes fit the other, making a distinction between the two species difficult.

Foothills, montane. Meadows, openings, streamsides. Summer, fall.
Wildcat Trail, August 28, 2007.

Linnaeus named the Aster genus in 1753 and John Lindley named this species in 1834 from a specimen collected by John Richardson on the Mackenzie River of Canada.  In 1995 Guy Nesom proposed moving many members of the genus "Aster" to the genus "Symphyotrichum"; that genus name is now accepted.  The Symphyotrichum genus was named by Christian Nees in 1832. 

"Spathulatum" means "spatula-shaped", perhaps referring to the leaf shape of the first collected specimens.

Foothills, montane. Meadows, openings, streamsides. Summer, fall.
Wildcat Trail, August 28, 2007.

Ray flower numbers can vary from 15-40 and rays can vary from 1-2 millimeters wide and 9-15 millimeters long. This flower head has about 32 rays whereas those in the above photographs have about 24.

In very bright sunlight, flowers of many species may appear white even though they are light blue/violet/purple. Notice the violet showing in the ray flowers in shade, especially at 4 and 7 o'clock.

Foothills, montane. Meadows, openings, streamsides. Summer, fall.
Boggy Draw Trails, September 26, 2013.

Almost all of the yellow tubular disc corollas have slipped off the white styles with their split ends. Below the styles you can see the pappus hairs.

Range maps © John Kartesz,
Floristic Synthesis of North America

State Color Key

Species present in state and native
Species present in state and exotic
Species not present in state

County Color Key

Species present and not rare
Species present and rare
Species extirpated (historic)
Species extinct
Species noxious
Species exotic and present
Native species, but adventive in state
Eradicated
Questionable presence

Range map for Symphyotrichum foliaceum

Range map for Symphyotrichum foliaceum var. apricum

Range map for Symphyotrichum foliaceum var. canbyi

Range map for Symphyotrichum foliaceum var. parryi

Range map for Symphyotrichum spathulatum