Taxon Report

Tuctoria mucronata (Crampt.) J. Reeder

Crampton's tuctoria or Solano grass

Print Report

Taxon Summary

Tuctoria mucronata, commonly known as Crampton's tuctoria or Solano grass, is a annual herb in the Poaceae that is found only in California. It occurs within Valley and foothill grassland (mesic), and Vernal pools, growing at elevations from 5 to 10 meters. Tuctoria mucronata is ranked 1B.1, Plants Rare, Threatened or Endangered in California and Elsewhere; Seriously threatened in California.

Classification


Scientific Name:	Tuctoria mucronata (Crampt.) J. Reeder
Common Name:	Crampton's tuctoria or Solano grass
Family:	Poaceae
Element Code:	PMPOA6N020
USDA Plants Symbol:	TUMU
Synonyms/Other Names:	Orcuttia mucronata Crampton

Ecology and Life History


Lifeform:	annual herb
Blooming Period: Apr-Aug	Apr-Aug
Elevation:	5-10 (15-35)
General Habitats:	Valley and foothill grassland, Vernal pools
Microhabitat:
Microhabitat Details:

Conservation Status


CA Rare Plant Rank:	1B.1
Global Rank:	G1
State Rank:	S1
State List:	CE
Fed List:	FE
Other Status:	SB_CalBG/RSABG
CRPR Changes:

Occurrence Data from the CNDDB


Total Occurrences:	4
Element Occurrence Ranks:
Excellent (A)	0
Good (B)	1
Fair (C)	2
Poor (D)	0
None (X)	0
Unknown (U)	1

Location


California Endemic: True
California Counties and Islands: Name (Code)
Solano (SOL), Yolo (YOL)
Quads: Name (Quad Code)
Dozier (3812137), Saxon (3812146)

Threat List Data from the CNDDB


Threat List Total:	7
EOs with Threat Listed:	Total EOs	% of EOs
	4	100 %
Non-native plant impacts	2	50%
Other	2	50%
Grazing	2	50%
Insufficient population/stand size	1	25%
Altered flood/tidal/hydrologic regime	1	25%
Over-collecting/poaching	1	25%
Recreational use (non-ORV)	1	25%

Notes



Known from only three occurrences: one at Olcott Lake at Jepson Prairie Preserve, one nearby on private land, and one south of Davis on DOD land. Only four plants found at Jepson Prairie in 1993, and none in 1994-1996, 1998, 2000 and later; site presumed extirpated in 2005. Threatened by non-native plants. See Madroño 15(4):106-108 (1959) for original description, and American Journal of Botany 69:1082-1095 (1982) for revised taxonomy.
Threats:

Taxonomy:

Selected References

Citation California Native Plant Society, Rare Plant Program. 2025. Rare Plant Inventory (online edition, v9.5.1). Website https://www.rareplants.cnps.org [accessed 5 February 2025].