Plants of the Eloise Butler Wildflower Garden

Stems: Calico Aster is a native perennial aster that grows on erect to ascending stems to 3 feet high with branching at the top of the stem. The lower stems have whitish hairs and are green initially but can turn reddish brown at flowering time.

Leaves are thin, lanceolate (broadest below the middle), alternate with lance-like tips, uppers and mid-stem leaves mostly stalkless, lower basal leaves with stalks, sometimes with a few sharp teeth from the middle to the tips of larger leaves. Lower leaves can be up to 5 inches long but usually drop off at flowering time. The upper surface is usually without hair but may have some roughness. The lower surface is much paler in color with hair on the mid-veins.

The floral array is a pyramidal form of an open panicle, formed by long-branched side stems that contain well spaced flowers on the upper sides of the branches, hence the alternate common name of "side-flowering."

The flowers have very small heads (about 1/3 inch wide) and have two types of florets: Around the outside are 8 to 15 ray florets with white to purple tinged rays, surrounding a central disc of 8-16 tubular disc florets that initially have cream to pale yellow colored corollas, but turn to darker reddish colors at maturity (which is typical of asters in this genus). The tip lobes of the disc floret corolla strongly reflex when the floret opens. The five stamens have reddish purple anthers and tightly surround the central style, which has appendages at its tip. The style is exserted from the corolla throat when the floret opens. The outside of the flower head is wrapped with small oblong to linear phyllaries in 3 to 4+ series, unequal in size, with green diamond shape tips, appressed tight against the head, infrequently spreading. Sometimes these take a purplish tone.

Seeds are a dry narrowly conical 3 to 5 ribbed cypsela, 1.8 to 2.2 mm long, with a tuft of whitish hair for wind dispersion. These cypselae can be very light in weight, being about 250,000 per ounce. Seeds usually germinate in warm locations without need for cold stratification, but if stored, storage must be dry cold.

Habitat: Side-flowering Aster grows from branched caudices or small rhizomes forming clumps. It grows best in rich, wet-mesic to dry-mesic soils with partial sun. Full sun will usually stress the plant unless there is continuous moisture. It is often found at woodland edges and other partially shaded openings.

Names: The older scientific name for this aster is Aster lateriflorus. All the new world asters, formerly in the genus Aster, have been reclassified, most into the genus Symphyotrichum. The genus name is from the Greek symphysis, for 'junction,' and 'trichos,' for hair and, while obscure, it was first applied by Christian Gottfried Daniel Nees von Esenbeck in the 1800s in describing the type aster for the genus. Both the older species name lateriflorus and the current lateriflorum refer to the lateral flowering branches. Classifying authorities often note a number of varieties of this species. There is no particular variety of this species recognized within Minnesota by either the DNR or the U of M Herbarium as native and authorities such as Flora of North America do not accept the varieties as they feel more research should be done.

The author names for the plant classification are: ‘A.Löve’ is for Áskell Löve (1916-1994) Icelandic botanist, co-founder of the Flora-Europaea project and professor at various universities in North America. ‘D.Löve’ is for Doris Löve (1918-2000), Swedish systematic botanist, active in the Arctic and collaborator with Áskell Löve on numerous publications. Together they amended the work of the first to classify the species - '(L.)' which refers to Carl Linnaeus (1707-1778), Swedish botanist and the developer of the binomial nomenclature of modern taxonomy.

Comparisons: The flowers are similar to the White Heath Aster in size, but the leaves are much larger than those of the Heath Aster; contrary wise, the leaves are shorter and more oval than those of White Panicle Aster. These latter two asters have flowers in dense clusters, not like the side flowering branches of this aster. The Ontario Aster, S. ontarionis, is similar but the underside of the leaves have hair, not just the mid-veins, the entire leaf is soft and flexible, the disc floret lobes spread, but not strongly reflex, and there are more ray and disc florets.