Taxon Report

Dieteria asteroides Torrey var. lagunensis (D.D. Keck) D.R. Morgan & R.L. Hartman

Mt. Laguna aster

Print Report

Taxon Summary

Dieteria asteroides var. lagunensis, commonly known as Mt. Laguna aster, is a perennial herb in the Asteraceae that is found in California and elsewhere. It occurs within Cismontane woodland, and Lower montane coniferous forest, growing at elevations from 790 to 2400 meters. Dieteria asteroides var. lagunensis is ranked 2B.1, Plants Rare, Threatened, or Endangered in California, But More Common Elsewhere; Seriously threatened in California.

Classification


Scientific Name:	Dieteria asteroides Torrey var. lagunensis (D.D. Keck) D.R. Morgan & R.L. Hartman
Common Name:	Mt. Laguna aster
Family:	Asteraceae
Element Code:	PDAST64131
USDA Plants Symbol:
Synonyms/Other Names:	Machaeranthera lagunensis Keck Machaeranthera asteroides (Torr.) Greene var. lagunensis (Keck) Turner

Ecology and Life History


Lifeform:	perennial herb
Blooming Period: (May)Jul-Aug	(May)Jul-Aug
Elevation:	790-2400 (2590-7875)
General Habitats:	Cismontane woodland, Lower montane coniferous forest
Microhabitat:
Microhabitat Details:

Conservation Status


CA Rare Plant Rank:	2B.1
Global Rank:	G5?T2
State Rank:	S1
State List:	CR
Fed List:	None
Other Status:	BLM_S; SB_CRES; USFS_S
CRPR Changes:	changed from 2.1 to 2B.1 on 2013-06-12

Occurrence Data from the CNDDB


Total Occurrences:	7
Element Occurrence Ranks:
Excellent (A)	0
Good (B)	2
Fair (C)	1
Poor (D)	0
None (X)	0
Unknown (U)	4

Location


California Endemic: False
California Counties and Islands: Name (Code)
San Diego (SDG)
Quads: Name (Quad Code)
Campo (3211654), Earthquake Valley (3311614), Jacumba (3211662), Mount Laguna (3211674)

Threat List Data from the CNDDB


Threat List Total:	8
EOs with Threat Listed:	Total EOs	% of EOs
	2	29 %
Grazing	2	28%
Road/trail construction/maint.	2	28%
Wood cutting or brush clearing	1	14%
Foot traffic/trampling	1	14%
Logging	1	14%
ORV activity	1	14%
Other	1	14%
Recreational use (non-ORV)	1	14%

Notes



Known in CA from fewer than 5 occurrences. Threatened by development, grazing and recreational activities. Potentially threatened by road maintenance. See Brittonia 9:238 (1957) for original description and SIDA 20(4): 1393 (2003) for revised nomenclature.
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 July 2025].