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iNaturalist — CC, credited & licensed per image
Ericaceae family

Island Manzanita Arctostaphylos insularis

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

Island Manzanita is a perennial shrub native to the lower 48 states. It blooms Jan – Sep. A host for pollen-specialist native bees.

More about this plant

Arctostaphylos insularis is a species of manzanita known by the common name island manzanita. It is endemic to Santa Cruz Island, one of the Channel Islands of California. 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
Perennial
Flower colour
White AI AI image-analysis of community-science photos (~87% expert agreement) — not a botanical record
In the garden
Shrub layer — Sits in the shrub 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 · Jan – Sep — 81 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 ~17 caterpillar species

Arctostaphylos supports ~17 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 moderate genus.

Recorded feeding on Arctostaphylos in North America, including:

Coleophora glaucella · casebearer moth ✦ Myelopsis alatella · snout moth ✦ Acronicta perdita · owlet moth Aethaloida packardaria · geometer (inchworm) moth Amorbia cuneanum · leafroller moth Amphipyra pyramidoides · Copper Underwing
+ 8 more species →
Anacamptodes clivinaria · Mountain Mahogany Looper Anarta cordigera · owlet moth Ancylis comptana · leafroller moth Antaeotricha manzanitae · concealer moth Apharetra californiae · owlet moth Argyrotaenia franciscana · Orange Tortrix Aseptis ethnica · owlet moth Aseptis fumeola · owlet moth
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). ✦ = recorded on this exact species.
✦ Bees specialist-bee host · 2 bee visitors

Specialist native bees depend on it.

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

Xerces pollinator conservation →

2 native & managed bee species are documented visiting Island Manzanita :

Bombus melanopygus · Black Tail Bumble Bee Xylocopa tabaniformis · Horsefly-Like Carpenter Bee
Specialist hosts from Smith et al. 2024. Visitor records (observations, not exhaustive) from Noori et al. 2026 (CC BY 4.0) · GloBI →
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 (17) 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
[14] Flower-visitor value (derived) — Noori et al. 2026 (CC BY 4.0) · GloBI
[15] Caterpillar host count — Warren II 2026 (Dryad, CC0) · Tallamy host-use counts
[16] Caterpillar species — NHM HOSTS (CC0)
[17] 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.
Cite this page Open data, please attribute

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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