COMMONLY USED HERBICIDES IN RANGE IMPROVEMENT

COMMON

NAME

TRADE

NAME

CHEMICAL NAME

COMMENTS

MODE OF ACTION

CLASS/FAMILY

Atrazine

Atrazine

Aatrex

2-chloro-4-

35hylamino-6-

isopropylamino-S-

triazine

Selective systemic, primarily root absorbed, some through foliage. Active on grass and broadleaf annuals mainly.

Inhibits photosynthesis and other enzymic processes.

S-Triazine

Clopyralid

Curtail

Curtail M

Stinger

3,b6-dichloro-2-

pyridinecarboxylic

acid

Selective systemic, postemergence, foliar with some root uptake broadleaf weeds, especially in the sunflower, legume and smartweed families.

Accumulates in meristematic tissue, acts on cell elongation and respiration. Exhibits an auxin-type reaction.

Pyridine

2,4-D

Several

2,4-dichlorophen-

oxy acetic acid

Selective systemic, foliar uptake broadleaf species, some woody species.

Acts as a growth inhibitor, accumulation mainly at meristematic region of shoots and roots.

Phenoxy

Dicamba

Banvel

3,6-dichloro-o-

anisic acid

Selective systemic, foliar and root uptake. Active on broadleaf and woody plant species.

Acts as an auxin-like growth regulator.

Benzoics

Glyphosate

Roundup Rodeo

N-(phosphono-

Methyl) glycine

Non-selective systemic, foliar uptake. Rodeo has aquatic sites label.

Inhibits amino acid biosynthesis, resulting in a reduction of protein synthesis and inhibition of growth.

Organophosphorus or Unclassified

MCPA

Several

2-Methyl-4-

chlorophenoxy-

acetic acid, and others

Selective systemic, postemergence, mainly absorbed by foliage. Active on woody and broadleaf species.

Hormone type, concentrates in meristematic regions where it inhibits growth.

Phenoxy

Metsulfuron

Methyl

Ally

Escort

Methyl 2-[[[[(4-

Methoxy-6-methyl-

1,3,5-triazin-2-yl)-

amino]carbonyl]-

amino]sulfonyl]

benzoate

Selective systemic, root and foliar uptake, active on broadleaf species.

Mitotic inhibitor/inhibits cellular division in the meristems, thus, stopping growth.

Sulfonylureas

Paraquat

Dichloride *

Cyclone Gramoxone Extra, Gramoxone Super

1,1’ –dimethyl-4,4’-

bipyridinium

dichloride

Non-selective contact herbicide somewhat translocated, absorbed by the foliage.

Absorbs energy produced during photosynthesis and forms peroxides and super oxides, which damage cell membranes and cytoplasm.

Bipyridylium

Picloram *

Tordon 22K

Tordon RTU

4-amino-3,5,6-

trichloropicolinic

acid

Selective systemic, root and foliar uptake, active on woody and broadleaf species.

Accumulates in new growth, alters nucleic acid and protein synthesis.

Picolinic Acid or Pyridine

Tebuthiuron

Spike

N-[5-(1,1-

Dimethylethyl)-

1,3,4-thiadiazol-2-yl]-N,N’-

dimethylurea

Systemic soil-herbicide, absorbed mainly by roots. Active on woody plants and vegetation.

Inhibits photosynthesis.

Substituted Ureas

Triclopyr+2,4-D

Crossbow

2,4-dichlorophen-

oxyacetic acid,(e,

5,6-trichloro-2-

pyridinyloxyacetic

acid), butoxyethyl

ester

Selective systemic, root and foliar uptake, active on woody and broadleaf species.

Growth regulator, mimics natural plant hormones.

Pyridine and Phenoxy

"Always read and follow label directions."

* Restricted Use Herbicide

Note: Other compounds are available, those listed may be more widely used and possibly easier to locate and purchase.

Some herbicides may have a CRP label only.

a Curtail has 2,4-D mixed in.

b Curtail M has MCPA mixed in.

Compiled by: James L. Wyatt

Sources: Crop Protection Chemicals Reference 1990. Chemical and Pharmaceutical Publishing Cororation, Sixth Edition. 2164p.

The Agrochemicals Handbook. The Royal Society of Chemistry. 1987., Second Edition pp. Always updated.

Herbicides and Their Properties and Application. Wyoming Weed Control Series, University of Wyoming Cooperative Extension Service.