Symphyotrichum sericeum

Taxobox
name = "Symphyotrichum sericeum"


image_width = 250px
regnum = Plantae
divisio = Magnoliophyta
classis = Magnoliopsida
ordo = Asterales
familia = Asteraceae
tribus = Astereae
genus = "Symphyotrichum"
species = "S. sericeum"
binomial = "Symphyotrichum sericeum"
binomial_authority = (Vent.) G.L.Nesom
synonyms = "Aster sericeus"
"Lasallea sericea"
"Virgulus sericeus"

"Symphyotrichum sericeum" is a species of flowering plant in the aster family known by several common names, including western silver aster and silky aster. It is native to central North America. "S. sericeum" is an aster of rocky prairies, wood glades, and gravel hill prairies. It ranges from the eastern prairies of the United States and Canada, west to the foothills of the Rocky Mountains; occurence is rare in the northeast part of its range. The plant is distinctive in the wild due to the silky texture; no other American aster is sericeous throughout. It is seldom found outside its preferred habitat. Compared to other American asters, the flowers appear disproportionately large for the plant's size.

This is a perennial herb growing from rhizomes. The stem is erect, sometimes branching. It is sericeous (silky) throughout, giving the stem a silvery-grey appearance. Basal leaves are oblanceolate in shape and have petioles. Cauline leaves, those growing along the stem, are ovate to ovate-lanceolate in shape, with alternate attachment to stem, sessile, acuminate at the base, acute at the tip. Leaf margins are entire, or smooth and lacking teeth or serration. Leaf texture is sericeous adaxally (above) and abaxally (below), giving the leaves a silvery-grey appearance. The inflorescence is terminal, occurring at the top of the stem, and consists of a single head. The involucre is ovate to lanceolate in shape and sericeous. Ray flowers are blue and fertile. Disc flowers are white, with stamens yellow to brown. The fruit is an achene.

"S. sericeum" is listed as a rare species in Indiana, and as a threatened species in Michigan.

External links

* [http://plants.usda.gov/java/profile?symbol=SYSE2 USDA Plants Profile]