Al Schneider's Rocky Mountains Plant Descriptions

Hoary Tansyaster
Dieteria canescens
Aster family (Asteraceae)

Dieteria canescens is a complex species with many variations. The plant is quite similar to Dieteria bigelovii. The latter has that are green at the tip and for at least half their length. D. canescens' are green only at the tip and the lower three-fourths of the is tan/white (often with a very narrow green stripe in the center). D. bigelovii's (the common of the flower cluster) are very sticky; D. canescens' are not. A hand lens will help you observe the these characteristics. Both species put on magnificent floral displays as each plant often has dozens of flowers in bloom at the same time and large areas are often covered with blooming plants -- especially in the fall along highways. "Canescens" is Latin for "becoming gray." Thomas Nuttall collected the first specimen of this plant for science on the banks of the Missouri in 1811.


©2012 Richard Spellenberg

Description

or , 16-32" tall, (without hairs) or finely hairy or sticky hairy leaves. Stems branching at top into numerous flowerheads. Each with a single flowerhead at the end. Flower consists of many narrow pink-lavender surrounding button of yellow flowers. () with green tip and buff sides and base. Leaves and .

Field Marks

Multiple purple composite flowers with yellow centers on many-branched stems.

© Al Schneider

ray flowers -- The outer petals of a sunflower or daisy are ray flowers.

A peduncle is a common stalk of a cluster of flowers.

A perennial plant lives and blooms for many years.

phyllaries -- Leaflike bracts covering the flowers before opening and remaining under the flower after it opens. Also called "bracts". Only used with the sunflower family (Asteraceae).

A herb is a plant whose stems die back to the ground in the winter.

Bracts are modified leaves associated with a flower.

Glands are plant structures that secrete liquids, salts or other substances. Glands often appear as hairs with a drop of liquid at the end.

Like the teeth on a saw, leaves and other surfaces can have toothed edges.

stalk -- The supporting structure of an organ. Examples of stalks are stem, peduncle, petiole, ...

biennial -- a plant which lives for two years, producing a basal rosette of leaves the first year and a full plant, flower, and seed the second year followed by the death of the entire plant at the end of the second year.

disc flowers are those in the center of a sunflower or daisy. Not a ray flower.

glabrous -- smooth, glossy, having no bristles or hair-like structures. Bald.

linear -- Long and very narrow like a blade of grass.