Carnegiea gigantea, Giant Saguaro

Southwest Desert Flora

Home to the plants of the Sonoran, Chihuahuan and Mojave Deserts

Cirsium ochrocentrum, Yellowspine Thistle

Psorothamnus schottii, Schott's Dalea

Schott's Dalea has showy indigo blue pea-like flowers that bloom from March to May. The type specimen of Psorothamnus schottii is from along the Colorado River (Schott). Psorothamnus schottii Schott's Dalea, Indigo Bush or Mesa Dalea has bright blue with 5 to 15 flowers on a racemose inflorescence. Psorothamnus schottii Schott's Dalea is an amazing shrub found in desert washes and sandy areas. It is very similar, superficially to Smoketree and also Mojave Indigobush with only a few taxonomic differences Psorothamnus schottii Schott's Dalea has small green linear leaves, persistent and visibly gland-dotted. Other species of Indigo Bush have persistent leaves. Psorothamnus schottii Schott's Dalea is a native shrub, relatively rare in the United States where it is found only Arizona and California. Psorothamnus schottii Schott's Dalea grows at elevations up to 2,000 feet and prefers slopes, benches and washes, sandy or gravelly. Psorothamnus schottii

Scientific Name: Psorothamnus schottii
Common Name: Schott's Dalea
Also Called: Indigo Bush, Mesa Dalea, Schott False Dalea, Schott's Dalea (Spanish: Jiguata)
Family: Fabaceae or Leguminosae Family
Synonyms: (Dalea schottii, Dalea schottii var. puberula)
Status: Native
Duration: Perennial
Size: Up to 6 feet.
Growth Form: Shrub; gray or green, strigose; arborescent with spinescent stems intricately branched.
Leaves: Green; simple, persistent, linear, gland-dotted.
Flower Color: Blue, bright blue; 5 to 15 flowers on a racemose inflorescence; glands in each interval between the calyx ribs 4 or fewer; calyx externally glabrous or nearly so, shining; fruit exserted, large glands.
Flowering Season: March to May (photos above; California; March, 2016.)
Elevation: Up to 2,000 feet.
Habitat Preferences: Slopes, benches, washes.
Recorded Range: Psorothamnus schottii is relatively rare, although common where found, in the United States, found only in small geographic areas in AZ and CA. In Arizona it occurs in the extreme southwest part of the state and in California in the far southeast part of the state. It is also native to Baja California and northwest Mexico.

North America & US County Distribution Map for Psorothamnus schottii.

U.S. Weed Information: No information available.
Invasive/Noxious Weed Information: No information available.
Wetland Indicator: No information available.
Threatened/Endangered Information: No information available.

Genus Information: In North America there are 9 species and 20 accepted taxa overall for Psorothamnus. World-wide, The Plant List includes 10 accepted species names and a further 37 infraspecific rank for the genus.

In the Southwestern United States: Arizona has 7 species of Psorothamnus, California has 6 species, Nevada has 5 species, New Mexico has 1 species, Texas has 1 species, Utah has 4 species. All data is approximate and subject to taxonomic changes.

Comments: Psorothamnus schottii an amazing shrub found in desert washes and sandy areas. It is very similar, superficially to Smoketree and also Mojave Indigobush with only a few taxonomic differences.

The type specimen of Psorothamnus schottii is from along the Colorado River (Schott).

In Southwest Desert Flora also see Smoketree, Psorothamnus spinosus.
Date Profile Completed: 02/15/2017
References:
Arizona Flora, Kearney, Thomas H., Peebles, Robert H., 1960, University of California Press, Berkley and Los Angeles, California; as Dalea schottii.
U.S. Dept. of Agriculture, Natural Resources Conservation Service on-line database and USGS ITIS search - (accessed 02/14/2017)
The Plant List (2013). Version 1.1. Published on the Internet; http://www.theplantlist.org/ (accessed 09/07/2015, 02/14/2017).
http://www.theplantlist.org/1.1/browse/A/Leguminosae/Psorothamnus/
https://plants.usda.gov/java/ClassificationServlet?source=profile&symbol=PSORO&display=31
Rhodes, Suzanne, June Beasley and Tina Ayers. 2011.Fabaceae. CANOTIA 7: 1-13. Journal of the Arizona-Nevada Academy of Science; Volume 7.
http://canotia.org/volumes/CANOTIA_2011_Vol7_Rhodes_et_al.pdf
The Jepson Desert Manual; 2002; Baldwin, Bruce G., et. al.; The Jepson Desert Manual: Vascular Plants of Southeastern California; p 325; Univ. of California Press, Berkeley and Los Angeles, California
Martin F. Wojciechowski & Duane Isely; eFlora Treatment; (accessed 02/14/2017)
http://ucjeps.berkeley.edu/eflora/eflora_display.php?tid=40164
1993, The Jepson Manual, Citation: http://ucjeps.berkeley.edu/interchange/I_treat_indexes.html (accessed 09/07/2015)
http://ucjeps.berkeley.edu/cgi-bin/get_JM_treatment.pl?3691,4186,4196
SEINet synonyms, scientific names, geographic locations, general information - (accessed ).
http://swbiodiversity.org/seinet/