Psilostrophe cooperi – Whitestem Paperflower

Psilostrophe cooperi - Whitestem Paperflower, Cooper's Paperflower

Psilostrophe cooperi - Whitestem Paperflower, Cooper's Paperflower

Plant Name

Scientific Name: Psilostrophe cooperi

Synonym: Riddellia cooperi

Common Names: Whitestem Paperflower, Cooper's Paperflower

Plant Characteristics

Duration: Perennial

Growth Habit: Subshrub, Herb/Forb

Arizona Native Status: Native

Habitat: Desert, Upland. These long-blooming wildflowers are common and widespread in the desert and lower elevation upland areas here.

Flower Color: Brilliant yellow, drying to cream

Flowering Season: Spring, Summer, Fall. The plants bloom repeatedly throughout much of the year.

Height: To 2 feet (61 cm) tall

Description: The flower heads are 1 inch (2.5 cm) wide and have 3 to 6, rounded, cupped, three-toothed rays. The flowers dry to a papery cream color on the plant. The leaves are grayish green, linear, and opposite. The distinctive stems are fuzzy and greenish white in color.

The similar Greenstem Paperflower (Psilostrophe sparsiflora) has green stems, while the also similar Woolly Paperflower (Psilostrophe tagetina) has gray-green stems.


Kingdom: Plantae – Plants
Subkingdom: Tracheobionta – Vascular plants
Superdivision: Spermatophyta – Seed plants
Division: Magnoliophyta – Flowering plants
Class: Magnoliopsida – Dicotyledons
Subclass: Asteridae
Order: Asterales
Family: Asteraceae – Aster family
Genus: Psilostrophe DC. – paperflower
Species: Psilostrophe cooperi (A. Gray) Greene – whitestem paperflower

More About This Plant

Arizona County Distribution Map