Colorado State University Extension and the Colorado State Forest Service publish Fact Sheet 6.305 for Colorado's WUI and varied ecosystems. FireApproved exposes all 114 exact source owners at Colorado publication scope while retaining score, elevation, water, and Idaho-carrier lineage. Publication scope is not suitability for every Colorado site or zone.
The guide presents itself as fire performance ratings for common landscape plants in a fire-prone California setting. FireApproved publishes 104 exact owners as republished California context. It is not an independent rating, a current endorsement, or parcel suitability.
The UC Forest Products Laboratory says the guide covers properties of common California landscaping plants and was prepared for California fire agencies. FireApproved publishes 130 exact owners at historical California publication scope. The report is a 1997 compilation, not a current endorsement, site rating, or independent test of every row.
Sun City Texas, Georgetown (TX footprint); partial normalized coverage · 2015-01-14
The guide is authored for the Sun City Texas community in Georgetown. FireApproved publishes 142 exact owners only as community-level context. It is an archived HOA exhibit with unknown rating lineage, not a current statewide Texas source or an independent Tier 1 determination.
2. Why this plant is relevant here
State distribution
Documented in CO.
Native range
Introduced / established
USDA hardiness
3. Legal, ecological, and broader status
Legal-list status
Seed-list status
Reported invasive here
Broader regional context
Federal context
How to read this page
The status above is computed from the cited rows below: independent recommendations can support a fire-resistant result, an avoid row can produce keep-away, and disagreement stays visible as conflict. Placement notes preserve each source’s own scheme rather than translating unlike rules into one scale. This is evidence about a plant, not permission to plant it in every part of the defensible space; Zone 0 remains noncombustible.
Where its sources say to plant it
Placement rules below use each source's own distances or named zones, tied to its rating.
They are not interchangeable with the directory's current Zone 0 guidance.
Ignition-Resistant Landscape Plants: suitable for defensible-space zones 1-2 (score 8+) [CSU defensible-space zone] (with its recommendation)
Defensible Space Landscaping in the Urban/Wildland Interf…: Chapter 4, Landscape Vegetation Database [ucfpl-1997] (with its recommendation)
Firewise Plant Guide: Perennials [Sun City plant-table sections] (with its recommendation)
Fire Performance of Common Plants: Table 1 (favorable in 3 or more references) [diablo-guide-to-plants-three-reference-vote] (with its recommendation)
The evidence
Grouped by what each source concluded. Primary evidence rated the plant itself
(a lab, field program, or original curation); corroboration compiled or
republished another source's rating and resolves to its root lineage.
The table rates Calylophus, Square Bud Primrose — Calyophus berlandieri low for flammability hazard, defined as the ease a plant can burn at high temperatures for a prolonged time.
Fire Performance of Common Plants (Guide to Plants) — Diablo Firesafe Council · live page captured 2026-08-29 · original sourceCorroborationMirrorlineage: ucfpl-berkeley resolves to Defensible Space Landscaping in the Urban/Wildland Interface: A Compilation of Fire Performance Ratings of Residential Landscape Plants
“Table 1: favorable fire performance rating in 3 or more references (refs 8,11,25,40,41)”
The Diablo Firesafe Council Guide to Plants lists Oenothera berlandieri (Mexican evening primrose) as groundcover, perennial, in Table 1: plants with a favorable fire performance rating in 3 or more references. The guide cites 5 of its 57 numbered references for this row (8,11,25,40,41). The guide states the ranking terms in its underlying references were mostly undefined and makes no attempt to rank within the list, and that fire performance is compromised without maintenance.
