Asters (6)
Asters are distinguished from Daisies by their phyllaries, which circle the under-side of the flower. Asters have phyllaries that overlap, like shingles. Daisies have phyllaries about the same length, like a fence. Asters bloom later in the summer than daisies. There are many asters. Here are a few. See also Purple Asters and Townsend Daisies.
Porter's Aster
Symphyotrichum porteri (Aster porteri)
Family:
Sunflower (Asteraceae)
AKA:
Smooth White Aster
Photo taken on:
August 1, 2008
Location:
Almont, CO
Life Zones:
Foothills to subalpine
Habitat:
Open fields and roadsides
Grows to 18" with wiry stems and smooth, narrow, bright green leaves. Flowers are small, to ¾" across. The bracts are three-tiered, green, and spread out from the base.
Flora of North America reference.
White Heath Aster
Symphyotrichum ericoides (Aster ericoides)
Family:
Sunflower (Asteraceae)
AKA:
Many-flowered Aster
Photo taken on:
September 29, 2008
Location:
Wet Mountains, Eastern CO
Life Zones:
Plains to foothills
Habitat:
Dry to moist soil, roadsides
Grows to 3 feet with twisted woody stems. The leaves are narrow and pointed as in heaths. The centers of the flower heads turn reddish-brown with age. Flowers grow in a cylindrical spike or a one-sided cluster. Bracts are green and hairy and curve out.
Flora of North America reference.
Rayless Alkali Aster
Symphyotrichum ciliatum
Family:
Sunflower (Asteraceae)
AKA:
Rayless Aster, Alkali American Aster
Photo taken on:
September 24, 2019
Location:
Russell Lakes State Wildlife Area, SLV, CO
Life Zones:
Plains to foothills
Habitat:
Moist brackish soil, roadsides
Grows to 2 feet high with a single, reddish stem. The leaves are thin and fleshy and usually withered by flowering. Flowers grow in a dense pyramid or a narrow cluster. Flower heads are narrow with long, narrow, spreading bracts and have no petals (ray flowers). The disk flowers are creamy white, sometimes pinkish. What appears to be yellow petals in the photo are yellowing bracts.
Flora of North America reference.
Flowers are 2" across and have a few twisted petals. The bracts are broad with purple edges.
Photo taken on:
August 12, 2007
Location:
Poverty Gulch, GV, CO
Leafy Aster
Symphyotrichum foliaceum var. canbyi (Aster foliaceus)
Family:
Sunflower (Asteraceae)
AKA:
Canby's Aster
Photo taken on:
August 11, 2007
Location:
Rustler Gulch, GV, CO
Life Zones:
Foothills to subalpine
Habitat:
Meadows, open woods
Grows from 8" to 24" high in clumps with showy flowers
1½" across .
Flowers range from white to
lavender.
Large leafy bracts identify this Aster. The longer outer bracts identify it as var. canbyi. The leaves growing from the stem are broad and clasping.
According to Flora of North America "Symphyotrichum foliaceum is extremely variable and is widespread in western montane coniferous forests and subalpine meadows", which is where I found them.
Charming Woody-Aster
Xylorhiza venusta
Family:
Sunflower (Asteraceae)
AKA:
Cisco Woodyaster
Photo taken on:
May 10 , 2010
Location:
Little Wildhorse Canyon, Utah
Life Zones:
Plains to foothills
Habitat:
Dry, open, saline soil
Grows up to 16" high. The leaves are ½" wide and oblong-shaped. Flower heads are one inch across with white to pale lavender rays. Bracts are green and curve out at the tips.
Flora of North America reference.