silky aster

not listed

N5? - Secure

SNR - Unranked

not listed

Silky aster is 8″ to 24″ tall, erect, perennial forb that rises on a cluster of 1 to 5 or more clustered stems from a short, woody, corm-like caudex or rhizome.

The stems are erect, thin, wiry, brittle, grayish-to reddish-brown, and much branched above the middle. They are hairless or nearly hairless near the base and are densely covered with appressed, silky hairs toward the tip.

Basal leaves are inversely lance-shaped, ⅝″ to 2″ long, and ⅛″ to ⅜″ wide. They are stalked, wedge-shaped at the base, and taper to a point at the tip with straight sides along the tip. There is 1 main vein and a network of smaller veins. The upper and lower surfaces are moderately to densely covered with long, silky hairs giving them a whitish- or grayish-green appearance. The margins are untoothed and have a fringe of silky hairs.

Lower stem leaves are similar to basal leaves but stalkless. They do not clasp the stem at the base. They have a short, sharp, abrupt point at the tip. Basal and lower stem leaves are usually absent at flowering.

Middle and upper stem leaves similar to lower stem leaves but lance-shaped, ⅜″ to 13 ⁄16″ long, 3 ⁄16″ to 5 ⁄16″ wide, and angled or rounded at the base.

The inflorescence is an open, branched array (panicle) at the end of the stems and branches. The panicle has 1 to 5 or more short-stalked flower heads per panicle branch.

The flower heads are ½″ to ¾″ in diameter. The bracts at the base of the flower head (involucre) is ¼″ to ⅜″ long and bell-shaped. They are arranged in 3 to 6 overlapping series. The outer series is egg-shaped, sharply pointed, and horizontally spreading. The middle series are bent backward. The inner series is linear and strongly ascending.

There are 10 to 30, usually at least 15, rose-purple to deep purple ray florets and 15 to 35, usually at least 25, disk florets. The disk florets are pink at first, later turning purple.

The fruit is a hairless, purple or brown achene with a tuft (pappus) of pale off-white or tan hairs attached.

8″ to 24″

Rose-purple to deep purple ray florets, pink disk florets

This is the only aster with leaves whitish-green due to a dense covering of silky hairs.

Dry. Prairies. Full sun.

August to October

Sources

2, 3, 4, 5, 7, 24, 28, 29, 30.

Native

Common

This and other asters were formerly place in the genus Aster. That genus was problematic, in that it did not include just one common ancestor with all of its lineal descendants and no others – it was not monophyletic. In 1994, the genus Symphyotrichum was resurrected to include most North American asters formerly in the genus Aster.

Silky Aster

Plant

Inflorescence

Flower

Buds

Location: Seven Sisters Prairie

Silky Aster