Psathyrotopsis scaposa (A. Gray) H. Rob.
Naked Turtleback, Naked Brittlestem
Asteraceae (Aster Family)
Synonym(s): Psathyrotes scaposa
USDA Symbol: PSSC14
A perennial, but often completing its life-cycle in one year. Few to many branches from one to three stems. "Leaves mostly basal; alternate; petiolate; blades rounded-deltate, lanceolate, or rhombic, margins crenate, serrate, or subentire, faces ± tomentose and stipitate-glandular." (Webref 3). Nearly globose discoid heads are born on terminal corymbose capitulescences. Disc flowers are white to yellow.
This is a species of the Chihuahuan Desert of West Texas, southern New Mexico and Chihuahua, Mexico.
From the Image Gallery
Plant CharacteristicsDuration: Annual , Perennial
Leaf Arrangement: Alternate
Leaf Complexity: Simple
Leaf Shape: Deltoid , Lanceolate
Leaf Pubescence: Glandular
Leaf Margin: Crenate , Serrate
Breeding System: Flowers Bisexual
Inflorescence: Corymb , Head
Size Notes: To about 16 inches in height. More often around 12 inches.
Leaf: "Leaf blades rounded-deltate, lanceolate, or rhombic." (Webref 3).
Flower: Ray florets lacking; disc florets yellowish-white to creamy-white.
Fruit: Fruit a narrowly obconic cypsela with a persistent pappus of 70 to 90 bristles. (Webref 3).
Bloom InformationBloom Color: White , Yellow
Bloom Time: Feb , Mar , Apr , May , Sep , Oct , Nov
Bloom Notes: Flowers white to bright yellow. February-May (June) and September-November (mostly following rains). (Webref 3), (Bibref 293).
DistributionUSA: NM , TX
Native Distribution: Texas, New Mexico and Chihuahua, Mexico.
Native Habitat: Gypseous and calcareous soils in creosote bush scrub-lands; 700–1300 m. (Webref 3).
Growing ConditionsWater Use: Low
Light Requirement: Sun
Soil Moisture: Dry
Soil pH: Alkaline (pH>7.2)
Drought Tolerance: Low
Heat Tolerant: yes
Soil Description: Gypseous or calcareous soils.
BibliographyBibref 293 - Manual of the Vascular Plants of Texas (1979) Correll, D. S. & M. C. Johnston
Search More Titles in Bibliography
Web ReferenceWebref 3 - Flora of North America (2014) Missouri Botanical Garden, St. Louis, MO & Harvard University Herbaria, Cambridge, MA.
Additional resourcesUSDA: Find Psathyrotopsis scaposa in USDA Plants
FNA: Find Psathyrotopsis scaposa in the Flora of North America (if available)
Google: Search Google for Psathyrotopsis scaposa
MetadataRecord Modified: 2018-05-03
Research By: Joseph A. Marcus