Home/Species/ Holmgren's Owl's-clover

Orthocarpus holmgreniorum

(T.I. Chuang & Heckard) L.M. Shultz & F.J. Smith

Holmgren's Owl's-clover

G2Imperiled Found in 7 roadless areas NatureServe Explorer →

G2ImperiledGlobal Rank

High - mediumThreat Impact

Identity

Unique IDELEMENT_GLOBAL.2.138329

Element CodePDSCR1H0S1

Record TypeSPECIES

ClassificationSpecies

Classification StatusStandard

Name CategoryVascular Plant

Endemicendemic to a single nation

KingdomPlantae

PhylumAnthophyta

ClassDicotyledoneae

OrderScrophulariales

FamilyOrobanchaceae

GenusOrthocarpus

Synonyms

Orthocarpus tolmiei ssp. holmgreniorumChuang & Heckard

Concept Reference

Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.

Conservation Status

Rank Method Rank calculation - Biotics v2

Review Date2021-10-27

Change Date2021-10-27

Edition Date2021-10-27

Edition AuthorsTreher (2021)

Threat ImpactHigh - medium

Range Extent1000-5000 square km (about 400-2000 square miles)

Number of Occurrences6 - 20

Rank Reasons

Orthocarpus holmgreniorum is a hemiparasitic annual herb that occurs in the western United States in the northern Wasatch Mountains and Bear River Range of southern Idaho and northern Utah. There are less than 10 known occurrences, most of which are in Utah. There are two historical occurrences in Idaho. Threats to this species include hikers and cattle, which trample plants. Climate change and exotic species are potential threats.

Range Extent Comments

Orthocarpus holmgreniorum occurs in the western United States in the northern Wasatch and Bear River Range from southeastern Idaho to north of Salt Lake City, Utah (Shultz and Smith 2018). The species was last documented in Idaho in 1916 (Franklin County) and 1922 (Caribou County) (L. Kinter, pers. comm., 2021).

Occurrences Comments

There are approximately 9-10 known occurrences based on a 1 km separation distance. All occurrences are in Utah, except for 1-2 historical occurrences in Idaho .

Threat Impact Comments

This taxon often grows along trails, where hikers may trample plants. At some occurrences, declines due to trampling by grazing cattle have been observed. Surveys are needed to further document threats. Climate change and exotic species are potential threats.

Ecology & Habitat

Habitat

This species grows in sagebrush meadows and slopes with shallow, rocky, clay soils (FNA 2019, Shultz and Smith 2018). Dominant associated plants include Artemisia arbuscula ssp. thermopola (Low Sagebrush), Madia glomerata (Tar Weed), and associated grasses (Shultz and Smith 2018).

Terrestrial Habitats

Shrubland/chaparralGrassland/herbaceous

Other Nations (1)

United StatesN2

Province	Rank	Native
Idaho	S1	Yes
Utah	S2	Yes

Threat Assessments

Threat	Scope	Severity	Timing
2 - Agriculture & aquaculture	Pervasive - large	Serious - moderate	High (continuing)
2.3 - Livestock farming & ranching	Pervasive - large	Serious - moderate	High (continuing)
2.3.4 - Scale unknown/unrecorded	Pervasive - large	Serious - moderate	High (continuing)
6 - Human intrusions & disturbance	Restricted - small	Serious or 31-70% pop. decline	High (continuing)
6.1 - Recreational activities	Restricted - small	Serious or 31-70% pop. decline	High (continuing)
8 - Invasive & other problematic species, genes & diseases	Small (1-10%)	Slight or 1-10% pop. decline	High (continuing)
8.1 - Invasive non-native/alien species/diseases	Small (1-10%)	Slight or 1-10% pop. decline	High (continuing)
8.1.1 - Unspecified species	Small (1-10%)	Slight or 1-10% pop. decline	High (continuing)

Plant Characteristics

DurationANNUAL

Economic Value (Genus)No

Roadless Areas (7)

Utah (7)

Area	Forest	Acres
Gibson	Wasatch-Cache National Forest	5,350
Mahogany Range	Wasatch-Cache National Forest	11,409
Mollens Hollow	Wasatch-Cache National Forest	17,690
Mt. Logan West	Wasatch-Cache National Forest	5,285
Mt. Naomi	Wasatch-Cache National Forest	41,922
Right Hand Fork Logan	Wasatch-Cache National Forest	15,023
Temple Peak	Wasatch-Cache National Forest	24,081

References (4)

Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.
Kinter, Lynn. Personal Communication. Botany Program Leader. Idaho Natural Heritage Program. Idaho Department of Fish and Game. Boise, ID
Shultz, Leila. Personal Communication. Botanist and Professor Emeritus. Utah State University, Logan, Utah.
Shultz, L.M., and F.J. Smith. 2018. Novelties in <i>Musineon </i>(Apiaceae) and <i>Orthocarpus </i>(Orobanchaceae) in the Northern Wasatch Mountains of Utah and Idaho. Madroño 65(1):60-64.

Orthocarpus holmgreniorum

Habitat

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