Unité de Malherbologie & Agronomie Weed Science & Agronomy INRA-Dijon

Bayer Code : bidtr

Scientific name: Bidens tripartita L.

Synonym(s) of Sc. name: Bidens comosa (Gray) Wiegand

Classification: Compositae, Dicotyledonous

Common name: trifid bur-marigold

Synonym(s) of Common name:

Name per country: DE : Dreiteiliger Zweizahn ; ES : cañamo acuatico ; FR : bident tripartite ; IT : forbicina comune ;

Biological type: Annual

Seed:

.

Seedling:

- Cotyledons linear (10 times longer than broad).

- Leaves entire deeply serrate.

Adult plant:

- Height 20-50 cm.

- Stem reddish, erect with spreading branches, nearly glabrous.

- Lower leaves entire. Leaves glabrous, opposite, petiolate with a winged petiole, deeply serrate. The upper leaves tripinnate, with lanceolate segments, the terminal one larger.

- Flowers yellow. Heads erect, isolated, tubular. Outer involucral bracts foliaceous, inner shorter ovate -lanceolate, scabrous, brown striated, receptacular scales linear-oblong.

- Fruits smooth, compressed, oblong, with barbed awns so that they can attach to clothing etc., brown-greenish, 5-6 mm long with 2 or 4 barbed bristles.

- Presence of triazine resistant populations in Austria.

- Biological type: annual.

Ecological profile (click on flags):   Rare       Rare       Present       Present       Rare    

Copyright © 2000-2001 INRA, all rights reserved ; J.-P. Lonchamp, Nov. 2000
http://www.dijon.inra.fr/bga/hyppa/hyppa-a/bidtr_ah.htm ,