Ulmus americana
American elm
(c) Douglas Goldman, some rights reserved (CC BY-SA), uploaded by Douglas Goldman · licence
Family: Ulmaceae · Type: Tree · Not Native
Ulmus americana (American elm) is a non-native California tree in the Ulmaceae family, recognized by size, bark pattern, leaf size, and spring fruiting.
American elm is a naturalized tree found in southern California coastal and Sacramento Valley regions along disturbed streambanks at elevations of 60 to 700 meters. Flowering from February to March, this tree produces small reddish-brown flowers before its leaves emerge in early spring. Growing up to 35 meters tall with distinctive bark that splits into ridges curving together at their ends, it has corky branches and red-brown winter buds. Its leaves are large elliptical blades 8.6 to 12.5 centimeters long with strongly double-serrate margins and sparse long hairs on the undersides. The fruit is an elliptical tan seed 0.9 to 1.3 centimeters long with densely ciliate margins.
Identification and appearance
Key characters: 3 sympatric species; distinguished by size, bark pattern, leaf size, and spring fruiting
Habitat and range
Habitat: Seeding along disturbed streambanks, or spreading by root suckers near old plantings
Elevation: 60-700 m
California counties: Los Angeles, Santa Barbara, San Diego, Sacramento, Butte, San Francisco, San Luis Obispo, Santa Cruz
Outside California: native to eastern United States
Bloom period
Ulmus americana blooms Feb-Mar.
How to tell it apart
vs Quercus: Ulmus has flat papery-winged fruits; oaks produce acorns in cups.; vs Alnus: Ulmus has round papery-winged fruits; alder has woody cone-like fruits.; vs Populus: Ulmus fruits are round papery wafers; Populus has cottony seeds on wind.; vs Platanus: Ulmus has individual papery-winged fruits; Platanus has spiky balls hanging on strings.; vs Fraxinus: Ulmus fruits are round papery wafers; ash fruits are single-winged paddles.
Frequently asked questions
Is Ulmus americana native to California?
No. Ulmus americana is not native to California (recorded as not native).
When does Ulmus americana bloom?
Ulmus americana blooms Feb-Mar.
Where in California does Ulmus americana grow?
Ulmus americana occurs in Los Angeles, Santa Barbara, San Diego, Sacramento, Butte, San Francisco, San Luis Obispo, Santa Cruz, at elevations of 60-700 m.
What plant family does Ulmus americana belong to?
Ulmus americana is in the Ulmaceae family, genus Ulmus.
What habitat does Ulmus americana grow in?
Ulmus americana grows in Seeding along disturbed streambanks, or spreading by root suckers near old plantings.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · Index of California Plant Names · CalPhotos
Last updated 2026-10-07
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.