Arctium lappa
Great burdock
(c) Rhonda Ridley, some rights reserved (CC BY-SA), uploaded by Rhonda Ridley · licence
Family: Asteraceae · Type: Herb · Not Native
Arctium lappa (Great burdock) is a non-native California herb in the Asteraceae family, recognized by (Arctium minus). Clear size and floral differences available.
Great burdock is a naturalized biennial found in southern North Coast Ranges Interior and San Francisco Bay Area in disturbed places at elevations below 500 meters. Flowering from June to October, this plant produces purple flowers in large heads approximately 9 to 12 millimeters long. Growing up to 2.5 meters tall with branches that ascend from its main stem, it develops a robust and expansive structure. Its large leaves can reach up to 80 centimeters in length, with green surfaces above and a distinctive grayish-white downy texture underneath. The fruit is approximately 6 to 7 millimeters long, often brown with occasional dark spotting.
Identification and appearance
Key characters: 1 sympatric species (Arctium minus). Clear size and floral differences available.
Habitat and range
Habitat: Uncommon. Disturbed places
Elevation: < 500 m
Outside California: widely naturalized in North America, native to Europe
Bloom period
Arctium lappa blooms Jun-Oct.
How to tell it apart
vs Cirsium: Arctium has hooked bract spines and spineless leaves; Cirsium has straight spines on both bracts and leaves.; vs Xanthium: Arctium has purple thistle-like flowers with hooked bracts; Xanthium has woody enclosed burrs containing 2 seeds.; vs Volutaria: Arctium has hooked spines on bracts; Volutaria has papery expanded bract tips without spines.; vs Centaurea: Arctium has hooked spines; Centaurea has fringed or spiny but not hooked bract tips.; vs Saussurea: Arctium has hooked bract tips; Saussurea has simple unadorned bract tips.
Frequently asked questions
Is Arctium lappa native to California?
No. Arctium lappa is not native to California (recorded as not native).
When does Arctium lappa bloom?
Arctium lappa blooms Jun-Oct.
What plant family does Arctium lappa belong to?
Arctium lappa is in the Asteraceae family, genus Arctium.
What habitat does Arctium lappa grow in?
Arctium lappa grows in Uncommon. Disturbed places.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · 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.