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Pictured: Juglans microcarpa — the species. This variety isn’t separately illustrated.
Juglandaceae family

Little Walnut (var. microcarpa) Juglans microcarpa var. microcarpa variety

Native

Little Walnut (var. microcarpa) is a perennial tree native to the lower 48 states. A keystone plant for native insects and the food web.

More about this plant

Juglans microcarpa, known also as the little walnut, Texas walnut, Texas black walnut or little black walnut, is a large shrub or small tree which grows wild along streams and ravines in Texas, New Mexico, Oklahoma, and Kansas, and the northernmost states of Mexico. It produces nuts with a width of 1/2—3/4 in. The pinnately compound leaves bear 7—25 untoothed to finely-toothed leaflets, each 1/4—1/2 in wide. It is found at elevations ranging from 700 ft to 6700 ft. Wikipedia →

Growing & care

USDA PLANTS · TRY
Conditions
Sources · Conditions
Cold hardiness (derived) — Hardiness
Hardiness
≥ zone 7 derived from its U.S. range
Size & form
Sources · Size & form
USDA PLANTS — Lifespan
Lifespan
Perennial
In the garden
Tree layer (canopy / understory) — Sits in the tree of a layered food forest or polyculture.Open guide →
derived roles
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 ~129 caterpillar species

Juglans supports ~129 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 an exceptional genus.

Recorded feeding on Juglans in North America, including:

Abagrotis alternata · Greater Red Dart Achatia distincta · Distinct Quaker Acrobasis angusella · Hickory Leafstem Borer Acrobasis caryivorella · Hickory Shoot Moth Acrobasis demotella · Walnut Shoot Moth Acrobasis indigenella · Leaf Crumpler Moth
+ 8 more species →
Acrobasis juglandis · snout moth Acrobasis juglanivorella · snout moth Acrobasis kearfottella · snout moth Acrobasis latifasciella · snout moth Acrobasis stigmella · snout moth Acronicta afflicta · Afflicted Dagger Moth Acronicta americana · American Dagger Moth Acronicta impleta · Yellow-Haired Dagger
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).
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.
Sources for this entry (11) 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
[06] Description — Wikipedia (CC BY-SA)
[07] Ecological value — Warren II 2026 (CC0) · Tallamy host-use counts
[08] Cold hardiness (derived) — Derived from U.S. range × USDA PHZM zones
[09] Caterpillar host count — Warren II 2026 (Dryad, CC0) · Tallamy host-use counts
[10] Caterpillar species — NHM HOSTS (CC0)
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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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