Al Schneider's Rocky Mountains Plant Descriptions

Slender Hawkweed
Hieracium triste
Aster family (Asteraceae)

Chlorocrepis tristisis a minutely slender plant often lost in the greenery of other more robust plants. Look for it blooming at high altitudes in late summer and early fall and a bit earlier as low as 7,500 feet. Flowerheads are usually covered with a mixture of longer -silvery hairs and shorter bristly- black hairs. In the manner common to many Asteraceae, fertilized flowers explode into a mass of hairs which will carry seeds on the winds. The name Hieracium triste was given by Carl Willdenow in 1826. William Jackson Hooker renamed the plant Hieracium gracile in 1833, and Love and Love renamed it Chlorocrepis tristis in 1975. "Hieracium" is from the ancient Greek "hierax," "a hawk." Pliny believed that hawks ate this plant to strengthen their eyesight. The common name for this plant is still "Hawkweed." "Tristis" is Latin for "dull."


©2010 Keir Morse

Description

with erect stems to 16" tall, hairy to . to 4", . Stem leaves small. Flowerheads about 1/3" tall and 1/5" wide, solitary or more commonly few flowered in cluster. cylindric, green black with starburst hairs and long black bristly hairs. Flowers all , yellow. an .

Field Marks

Tall slender plant with few, cylindrical yellow flowers and covered in black hairs.

© Al Schneider

silky -- Covered with fine soft hairs, with a lustrous sheen. Satiny to the touch.

petiolate -- a leaf that has a stem. A sessile leaf has no stem.

A perennial plant lives and blooms for many years.

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

achene -- a type of simple dry fruit produced by many species of flowering plants. For example, a rose hip holds a few achenes.

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

Involucre is the name given to the circle or spiral collection of bracts around a flower-cluster.

pappus -- Small scales, bristles or hairs at the top of the seed in Asteraceae. For example, dandelion parachutes. Plural: pappi.

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

fruit -- any seed-bearing structure in flowering plants. It is formed from the ovary after flowering.

basal leaves -- a leaf that grows lowest on the stem of a plant.

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