Common name: dicamba

U.S. trade name: BANVEL

Leaf curling and cupping in velvetleaf (Abutilon theophrasti) following dicamba post-emergent (POST) application

3,6-dichloro-2-methoxybenzoic acid.

Benzoic acids.


4.

Corn, wheat, barley, rye, oats, turf, utility rights-of-way.

Annual, biennial, perennial BLW (broadleaf weeds); brush species; conifers; especially velvetleaf, Canada thistle, field bindweed & various triazine-resistant BLW.

PRE and POST in corn (POST only for others).

Readily absorbed by roots, stems, foliage and then translocated to other plant parts. Moves both through xylem and phloem (apoplast and symplast).

Disruption of transport systems and interference with nucleic acid metabolism.

Not completely understood;but similar to that of the endogenous auxin: indole acetic acid (IAA); specific site of action has not yet been identified.

Metabolized to non-toxic compounds by tolerant species.

Induces abnormal growth typical of growth-hormone herbicides ('epinastic bending'). Twisting, bending of stems and petioles; leaf curling and cupping and development of abnormal tissues and secondary roots. Plant death occurs from growth abnormalities - symptoms occur within hrs of application but death is a slow process: 3-5 wks.

Intermediate (1-4 months); no problem in subsequent season if applied at recommended rates.

oral LD₅₀ = 1707 mg/kg - moderately toxic (BANVEL = 2629 mg/kg- slightly toxic).

Control is best when weeds are small and actively growing; high rainfall or cold temperatures after application may cause temporary corn injury, especially early in season; spray drift may be a problem, especially at high temperatures [>25°C (75°F)]; often tank-mixed with grass herbicides/or phenoxys to increase spectrum of control.