Calystegia occidentalis (chaparral false bindweed)

Plate 1 figs. a–h · 8 separate observations

Calystegia occidentalis, photographed by Millie Basden — fig. a Millie Basden, CC BY 4.0 / 2022-04-29 / obs. 192226094

Calystegia occidentalis, photographed by Diego Blanco — fig. b Diego Blanco, CC0 1.0 / obs. 148906463

Calystegia occidentalis, photographed by Trevor Van Loon — fig. c Trevor Van Loon, CC BY 4.0 / obs. 133027796

Calystegia occidentalis, photographed by George Raymond — fig. d George Raymond, CC0 1.0 / obs. 79020727

Calystegia occidentalis, photographed by Jim Dreier — fig. e Jim Dreier, CC BY 4.0 / obs. 116950481

Calystegia occidentalis, photographed by Adam J. Searcy — fig. f Adam J. Searcy, CC BY 4.0 / obs. 107166894

Calystegia occidentalis, photographed by Don Loarie — fig. g Don Loarie, CC BY 4.0 / obs. 3851956

Calystegia occidentalis, photographed by Ken-ichi Ueda — fig. h Ken-ichi Ueda, CC BY 4.0 / obs. 3346173

Every figure is a research-grade observation under CC0, CC BY or CC BY-SA, rehosted with the photographer’s name, the licence and the observation it came from. Photographs under a NonCommercial licence are excluded from this site and are never stored, which costs us a great many pictures and is not negotiable.

Native range 2 botanical countries

Native distribution of Calystegia occidentalis, after Kew’s World Checklist of Vascular Plants. Introduced, extinct and doubtful records are excluded, so this is where the plant is from, not everywhere it now grows.

Region	TDWG code	Continent
California	CAL	NORTHERN AMERICA
Oregon	ORE

Region boundaries approximated from Natural Earth (public domain) and mapped to TDWG World Geographical Scheme for Recording Plant Distributions (WGSRPD) level-3 botanical countries (Brummitt 2001). Indicative, not the official WGSRPD geometry.

Flowering 131 in flower of 138 examined

100%

98%

75%

Proportion of examined Calystegia occidentalis in flower, by month
Month	In flower	Examined	Share	95% interval
Jan	1	1	too few examined
Feb	0	0	too few examined
Mar	2	2	too few examined
Apr	11	11	100%	74% to 100%
May	52	53	98%	90% to 100%
Jun	54	55	98%	90% to 100%
Jul	6	8	75%	41% to 93%
Aug	3	4	too few examined
Sep	1	3	too few examined
Oct	1	1	too few examined
Nov	0	0	too few examined
Dec	0	0	too few examined

Peak flowering in Apr. Each bar is the share of Calystegia occidentalis observations in which someone actually recorded the reproductive state and found the plant in flower, not the raw number of flowering records. That distinction matters: people observe plants far more in spring than in winter, so a bare count of flowering records partly measures when people go outside. Dividing by the number examined removes that. 131 of 138 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. 8 months have fewer than 5 examined observations, so no proportion is drawn for them. This is still a global aggregate and not a forecast for your garden: the same species flowers on different dates in different hemispheres. Where a species has fewer than 30 flowering records we do not draw this chart at all. Computed from 10.15468/dl.cgje2x.

Also published as 22 synonyms

A synonym is not an error. It is a record of botanists disagreeing, in print, about where this plant belongs. Each of these was somebody’s considered answer.

Calystegia fulcrata (A.Gray) Brummitt
Calystegia fulcrata subsp. gracilenta (Greene) Brummitt
Calystegia fulcrata subsp. tomentella (Greene) Brummitt
Calystegia fulcrata var. deltoidea (Greene) Brummitt
Calystegia malacophylla subsp. tomentella (Greene) Munz
Calystegia malacophylla var. deltoidea (Greene) Munz
Calystegia polymorpha (Greene) Munz
Convolvulus auriculifolius Eastw.
Convolvulus deltoideus Greene
Convolvulus fruticetorum Greene
Convolvulus fulcratus (A.Gray) Greene
Convolvulus fulcratus var. deltoideus (Greene) Jeps.
Convolvulus gracilentus Greene
Convolvulus luteolus var. fulcratus A.Gray
Convolvulus occidentalis A.Gray
Convolvulus occidentalis subsp. fruticetorum (Greene) Abrams
Convolvulus occidentalis subsp. occidentalis
Convolvulus occidentalis var. occidentalis
Convolvulus polymorphus Greene
Convolvulus purpuratus var. fruticetorum (Greene) House
Convolvulus tomentellus Greene
Convolvulus villosus var. fulcratus (A.Gray) A.Gray

Sourcesevery claim on this page

World Flora Online Plant List. accepted name, authority, classification. CC0. Retrieved 2026-07-12.
iNaturalist. photographs and flowering annotations, CC0 / CC BY / CC BY-SA only. per photograph. Retrieved 2026-06-27.
Wikidata. common name (P1843), joined on the World Flora Online identifier (P7715). CC0. Retrieved 2026-07-13.
Kew, World Checklist of Vascular Plants (WCVP v16). native distribution by TDWG level-3 botanical country, and life form. CC BY 3.0. Retrieved 2026-06-04.

We publish what we can source and we say so when we cannot. This page has no care advice and no toxicity claim, because we do not yet have those from a source we can cite.