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iNaturalist — CC, credited & licensed per image
Polygonaceae family

San Jacinto Buckwheat Eriogonum apiculatum

Native Specialist-bee host
Late-season nectar — Flowers in a late-autumn window when few other plants in our catalog bloom — valuable late forage for pollinators (relative to our catalog's bloom coverage).

San Jacinto Buckwheat is an annual wildflower native to the lower 48 states. It blooms Jul – Oct. A host for pollen-specialist native bees.

More about this plant

Eriogonum apiculatum is a species of wild buckwheat known by the common name San Jacinto buckwheat. It is endemic to California, where it is known from the San Jacinto, Santa Rosa, Palomar, and Cuyamaca Mountains of San Diego and western Riverside Counties. Its habitat includes chaparral and wooded slopes on granite sands. This is an annual herb producing a spreading to erect, glandular stem up to 90 centimeters tall. The oblong leaves appear at the base of the plant. They are hairy and glandular in texture. Most of the stem is made up of the inflorescence, branching, spindly cyme with clusters of flowers at the tips of the branches. The individual flowers are under 3 millimeters wide and are white in color with reddish stripes. Wikipedia →

Growing & care

USDA PLANTS · TRY
Conditions
Sources · Conditions
Cold hardiness (derived) — Hardiness
Hardiness
≥ zone 11 derived from its U.S. range
Size & form
Sources · Size & form
USDA PLANTS — Lifespan
McKenzie et al. 2025 — community-science image analysis (MIT) — Flower colour
Lifespan
Annual
Flower colour
White AI AI image-analysis of community-science photos (~87% expert agreement) — not a botanical record
In the garden
Herb layer — Sits in the herb of a layered food forest or polyculture.Open guide →
derived roles
AI = read by an AI vision model · DERIVED = a computed estimate, not a direct measurement. The “How we know this” section below details each.
The garden year bloom → fruit → fall colour
J
F
M
A
M
J
J
A
S
O
N
D
Bloom
Bloom (the flower's colour)
Bloom · Jul – Oct — 103 obs · Herbarium specimens — Park et al. 2023 (CC BY 4.0)
Species characteristics from USDA PLANTS (public domain) + TRY (CC BY) — general guidance, not a guarantee for your exact site. Deer "browsing" is documented palatability, not a deer-proof claim.

Wildlife & pollinators

How pollinator value is scored →
❧ Caterpillar hosts ~9 caterpillar species

Eriogonum supports ~9 caterpillar species.

Native butterfly & moth caterpillars are the base of the terrestrial food web — most songbirds rear their young almost entirely on them. As a host for native Lepidoptera this is a modest genus.

Recorded feeding on Eriogonum in North America, including:

Anacamptodes fragilaria · geometer (inchworm) moth Aplectoides condita · Quivering Dart Moth Apodemia mormo · Mormon Metalmark Argyrotaenia citrana · leafroller moth Argyrotaenia franciscana · Orange Tortrix Aroga eriogonella · twirler moth
+ 8 more species →
Callophrys affinis · Western Green Hairstreak Callophrys apama · Canyon Green Hairstreak Callophrys comstocki · gossamer-winged butterfly Callophrys dumetorum · Lotus Hairstreak Callophrys lemberti · gossamer-winged butterfly Callophrys sheridanii · Sheridan's Hairstreak Callophrys viridis · gossamer-winged butterfly Chalceria heteronea · gossamer-winged butterfly
Keystone count (genus-level) from Warren II 2026 (CC0) · Tallamy host-use records. Named species (a documented Nearctic sample, not exhaustive) from NHM HOSTS (CC0).
✦ Bees specialist-bee host

Specialist native bees depend on it.

Some native bees are pollen specialists (oligolectic) — they raise young only on pollen from particular plant genera. Eriogonum is a recorded specialist-bee host, so losing it can mean losing the bee that relies on it.

Xerces pollinator conservation →
Specialist hosts from Smith et al. 2024.
Species thumbnails re-hosted from iNaturalist — Creative Commons, credited per image (hover for credit). Click any species to see it on iNaturalist. Not exhaustive; many taxa have no openly-licensed photo yet.
How we know this (1) Methods & honest limits
Flower colour Derived

McKenzie et al. assigned each species a flower colour with a GPT-4V vision model over iNaturalist photos. We use the confident tier plus a separately-labelled lower-confidence top-up (mostly inconspicuous green/brown flowers), and render it as a small tint — never as an asserted fact, and kept out of the written synopsis.

Honest limits: AI image inference (~87% expert agreement on the confident tier); a decorative, confidence-tiered indicator, not a measured trait.

McKenzie, P., Berardi, A.E., Hopkins, R. (2025). flower_color_phenology (MIT).
Derived values are computed from open data by a published method — labelled, cited, and never shown as a direct observation. Full methodology →
Sources for this entry (15) Open & cited
[01] Scientific name & family — USDA PLANTS (DwCA, Zenodo 17903503)
[02] Growth habit & duration — USDA PLANTS (DwCA, Zenodo 17903503)
[03] Native status & distribution — USDA PLANTS (DwCA, Zenodo 17903503)
[04] Common name — USDA PLANTS (via GBIF)
[05] Invasive / introduced status — USDA PLANTS (DwCA, Zenodo 17903503) — native status
[07] Description — Wikipedia (CC BY-SA)
[08] Ecological value — Warren II 2026 (CC0) · Tallamy host-use counts · Smith et al. 2024 (CC BY)
[10] Conservation rank — NatureServe Explorer (CC BY)
[11] Cold hardiness (derived) — Derived from U.S. range × USDA PHZM zones
[13] Caterpillar host count — Warren II 2026 (Dryad, CC0) · Tallamy host-use counts
[14] Caterpillar species — NHM HOSTS (CC0)
[15] County range — GBIF Open Data — open-licensed occurrences (CC0/CC-BY) → county
Spot an error or have a better photo? Every field links to its source, and the whole dataset is open.
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PlantKey’s data is open under CC BY-SA 4.0 — free to reuse and adapt, with attribution and the same licence. Photos keep their own per-image licence + credit (see Sources above).

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