Volutaria tubuliflora
Egyptian knapweed, Canary Islands Knapweed
(c) Álvaro Parra Valdivia, some rights reserved (CC BY) · licence
Family: Asteraceae · Type: Annual · Not Native
Conservation status: Cal-IPC Yes
Volutaria tubuliflora (Egyptian knapweed) is a non-native California annual in the Asteraceae family.
Egyptian knapweed is a naturalized annual found in western Sonoran Desert near Borrego Springs in disturbed ground and seasonally flooded sites at elevations of up to 250 meters. Flowering from February to June, this plant produces white to purple flowers in clustered heads 10 to 15 millimeters long with distinctive white-margined, spine-tipped phyllaries. Growing up to 1.5 meters tall with branching stems that become increasingly glandular and cobwebby, the plant develops widely elliptic to oblanceolate leaves that become deeply lobed with dentate edges. Its leaves are characterized by proximal leaves that are widely elliptic, with middle leaves creating decurrent toothed wings along the stem, and distal leaves becoming progressively smaller and bract-like. The fruit is pale gray-brown, 3 to 3.5 millimeters long, and covered in ascending hairs.
Identification and appearance
Key characters: 0 sympatric species - geographically isolated in western Sonoran Desert
Habitat and range
Habitat: Disturbed ground, seasonally flooded sites
Elevation: <= 250 m
Outside California: northern Africa, introduced Arabian Peninsula, South America
Bloom period
Volutaria tubuliflora blooms Feb-Jun.
Conservation status
Cal-IPC Yes
How to tell it apart
vs Centaurea: Volutaria bract margins smooth/minutely toothed; Centaurea bract tips fringed with multiple spines or teeth; vs Lessingia: Lessingia has bristly pappus and annual taproot; Volutaria has scaly pappus and smooth-spined bracts; vs Tanacetum: Tanacetum has fern-like leaves and buttonlike flowers; Volutaria simple leaves and spiny-bracted heads; vs Arctium: Arctium bracts hooked at tips; Volutaria bracts with straight flattened spines; vs Saussurea: Saussurea bracts not spine-tipped; Volutaria bracts taper to distinct flattened spines
Frequently asked questions
Is Volutaria tubuliflora native to California?
No. Volutaria tubuliflora is not native to California (recorded as not native).
When does Volutaria tubuliflora bloom?
Volutaria tubuliflora blooms Feb-Jun.
What plant family does Volutaria tubuliflora belong to?
Volutaria tubuliflora is in the Asteraceae family, genus Volutaria.
Is Volutaria tubuliflora invasive in California?
Volutaria tubuliflora is listed by Cal-IPC with an invasiveness rating of Yes.
What habitat does Volutaria tubuliflora grow in?
Volutaria tubuliflora grows in Disturbed ground, seasonally flooded sites.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · CalPhotos
Last updated 2026-09-30
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.