Taxon Report

Trifolium piorkowskii Rand. Morgan & A.L. Barber

maverick clover

Print Report

Taxon Summary

Trifolium piorkowskii, commonly known as maverick clover, is a annual herb in the Fabaceae that is found only in California. It occurs within Chaparral, Cismontane woodland, Lower montane coniferous forest, Valley and foothill grassland (mesic), and Vernal pools, growing at elevations from 160 to 680 meters. Trifolium piorkowskii is ranked 1B.2, Plants Rare, Threatened or Endangered in California and Elsewhere; Moderately threatened in California.

Classification


Scientific Name:	Trifolium piorkowskii Rand. Morgan & A.L. Barber
Common Name:	maverick clover
Family:	Fabaceae
Element Code:	PDFAB40410
USDA Plants Symbol:	TRPI2
Synonyms/Other Names:

Ecology and Life History


Lifeform:	annual herb
Blooming Period: Apr-May	Apr-May
Elevation:	160-680 (525-2230)
General Habitats:	Chaparral, Cismontane woodland, Lower montane coniferous forest, Valley and foothill grassland, Vernal pools
Microhabitat:	Clay, Openings, Streambanks (often), Volcanic
Microhabitat Details:

Conservation Status


CA Rare Plant Rank:	1B.2
Global Rank:	G2
State Rank:	S2
State List:	None
Fed List:	None
Other Status:
CRPR Changes:	changed from CBR to 1B.2 on 2018-01-30 Considered But Rejected on 2016-11-10

Occurrence Data from the CNDDB


Total Occurrences:	5
Element Occurrence Ranks:
Excellent (A)	0
Good (B)	0
Fair (C)	0
Poor (D)	0
None (X)	0
Unknown (U)	5

Location


California Endemic: False
California Counties and Islands: Name (Code)
Shasta (SHA)
Quads: Name (Quad Code)
Oak Run (4012261), Redding (4012254), Shingletown (4012148), Tuscan Buttes Ne (4012241)

Threat List Data from the CNDDB


Threat List Total:	0
EOs with Threat Listed:	Total EOs	% of EOs
	0	%

Notes



Possibly threatened by grazing, trampling, vehicles, and mining. Similar to, and previously identified as, T. fucatum. See Novon 23(1):65-69 (2014) for original description.
Threats:

Taxonomy:

Selected References

CRPR List Addition on 2018-01-30

Citation California Native Plant Society, Rare Plant Program. 2025. Rare Plant Inventory (online edition, v9.5.1). Website https://www.rareplants.cnps.org [accessed 7 December 2025].