Amino Acid Inhibitors

Glyphosate

Applied primarily to genetically engineered, glyphosate-resistant varieties of soybeans, corn, canola and cotton. Also applied to control woody plants. Because of its broad spectrum and relatively low toxicity to animals, it is used in horticulture and in the control of aquatic macrophytes.

Applied to the foliage and transported with sugars to metabolic sites where they inhibit amino acid production. Effects will manifest in two or more weeks as discoloration of foliage and deformations in new growth.

Imazethapyr

Applied to control weeds in alfalfa, barley, soybeans and wheat.

Thifensulfuron

Applied to control weeds in small grains, soybeans and corn and in conifer and hardwood plantations.

Photosynthesis Inhibitors

Atrazine

Applied to crops such as corn, soybeans and sorghum, particularly for conservation tillage.

These broad spectrum herbicides are applied at the soil and carried to the leaves by transpiration. They inhibit photosynthesis.

Cyanazinet

Synthetic Auxin, Growth Regulators

2,4-D

Applied to broad-leafed weeds in corn, small grains, sorghum, pastures and rangeland. Urban use on lawns and grassy rights of way. Also applied for control of broad-leafed trees when planting conifers.

These synthetic growth hormones are applied to the foliage of dicots and transported to meristems causing uncontrolled growth. Effects can be observed as discoloration of foliage and deformations in new growth. They are fast acting: effects on foliage are visible within minutes of application.

Dicamba

Cell Division Inhibitors

Trifluralin

Applied to control grasses and broadleaf weeds in crops such as beans, peanuts, cotton and tobacco.

These herbicides are applied to the soil to control target vegetation before emergence by inhibiting root growth.

Pendimethalin

Metolachlor

Applied pre-planting to control annual grasses and broadleaf weeds among crops such as corn and soybeans.

This herbicide is applied to the soil to control target vegetation by inhibiting or disrupting cell division in shoots.