Name That Weed!
Find Your Weed, Fix Your Field
START HERE
Look at the weed’s leaves
Thin leaves like grass
Wide leaves
How does it grow?
Grows in bunches
Spreads underground
How are leaves arranged on the stem?
Side by side
Leaves staggered (alternate)
Which looks right?
Foxtail
Barnyardgrass
Which looks right?
Johnsongrass
Quackgrass
Which looks right?
Velvetleaf
Common Ragweed
Look at the stem base carefully
⚠️ Smooth stems, NO HAIR
Hairy stems
🚨 Geometric leaf pattern
⚠️ Waterhemp
Smooth stems, no hair, waxy leaves
Herbicide Recommendations
Pre-emerge: Dual Magnum, Boundary, Verdict
Post-emerge: Liberty, Flexstar, Cobra
AVOID: Only Group 2, 5, or 9
Post-emerge: Liberty, Flexstar, Cobra
AVOID: Only Group 2, 5, or 9
Growth Stage Guidance
Control before 4″ tall. Germinates all season. Most vulnerable at 2-4 leaf stage.
Resistance Management
Multiple MOAs required. Resistant to Groups 2, 5, 9, 14, 27. Use layered residuals.
🚨 Palmer Amaranth
Geometric leaves, long petioles, hairless
Herbicide Recommendations
Pre-emerge: Warrant, Zidua, Anthem Flex
Post-emerge: Liberty, Enlist, XtendiMax
AVOID: Single MOA applications
Post-emerge: Liberty, Enlist, XtendiMax
AVOID: Single MOA applications
Growth Stage Guidance
Control before 3″ tall. Grows 2-3 inches per day. Can reduce yields 70-90%.
Resistance Management
ZERO TOLERANCE for escapes. Resistant to multiple groups. Hand-rogue if found.
Redroot Pigweed
Hairy stems, notched leaf tips, red roots
Herbicide Recommendations
Pre-emerge: Atrazine, metribuzin, S-metolachlor
Post-emerge: 2,4-D, dicamba, Callisto
Multiple options available
Post-emerge: 2,4-D, dicamba, Callisto
Multiple options available
Growth Stage Guidance
Control before 6″ tall. Less competitive than Waterhemp. Watch for late-season escapes.
Resistance Management
Some Group 2 resistance reported. Use multiple MOAs. Monitor for poor control.
Foxtail
Fox tail seed head, multiple types (green, yellow, giant)
Herbicide Recommendations
Pre-emerge: Dual, Outlook, Prowl H2O
Post-emerge: Select Max, Assure II, Fusilade
Good grass herbicide options
Post-emerge: Select Max, Assure II, Fusilade
Good grass herbicide options
Growth Stage Guidance
Control before seed head formation. Multiple flushes possible. Less competitive than broadleaves.
Resistance Management
Some Group 1 resistance. Rotate grass herbicide MOAs. Use pre-emerge for best control.
Barnyardgrass
No ligule, purple-tinged base, flattened stems
Herbicide Recommendations
Pre-emerge: Command, Dual, Prowl
Post-emerge: Clincher, Select, Raptor
Responds well to grass herbicides
Post-emerge: Clincher, Select, Raptor
Responds well to grass herbicides
Growth Stage Guidance
Control before heading. Thrives in wet conditions. Can be very competitive in rice.
Resistance Management
Some Group 1 resistance. Use multiple MOAs. Good cultural control with crop competition.
Johnsongrass
Large seed head, prominent midrib, spreads by rhizomes
Herbicide Recommendations
Pre-emerge: Dual, Outlook, Zidua
Post-emerge: Roundup, Select, Assure II
Rhizome control requires systemic herbicides
Post-emerge: Roundup, Select, Assure II
Rhizome control requires systemic herbicides
Growth Stage Guidance
Control before 18″ tall. Rhizomes make it persistent. Most vulnerable at early growth stages.
Resistance Management
Some glyphosate resistance. Use multiple MOAs. Focus on rhizome control for long-term management.
Quackgrass
Clasping auricles, rhizome spreader, waxy leaves
Herbicide Recommendations
Pre-emerge: Limited options due to rhizomes
Post-emerge: Roundup, Select, Poast
Systemic herbicides needed for rhizome control
Post-emerge: Roundup, Select, Poast
Systemic herbicides needed for rhizome control
Growth Stage Guidance
Control at early boot stage for best rhizome kill. Very persistent due to underground stems.
Resistance Management
Few resistance issues but difficult to control. Focus on preventing spread to new fields.
Velvetleaf
Heart-shaped leaves, velvety texture, button-like seed pods
Herbicide Recommendations
Pre-emerge: Atrazine, metribuzin, S-metolachlor
Post-emerge: Liberty, Cobra, Flexstar
Multiple effective options available
Post-emerge: Liberty, Cobra, Flexstar
Multiple effective options available
Growth Stage Guidance
Control before 8″ tall. Very competitive. Can produce many seeds that persist in soil.
Resistance Management
Few resistance issues. Good crop competition helps control. Rotate herbicide sites of action.
Common Ragweed
Fern-like leaves, opposite arrangement, causes allergies
Herbicide Recommendations
Pre-emerge: Atrazine, metribuzin, Authority
Post-emerge: 2,4-D, dicamba, Liberty
Generally easy to control
Post-emerge: 2,4-D, dicamba, Liberty
Generally easy to control
Growth Stage Guidance
Control before 6″ tall. Common in disturbed soils. Can be competitive if left uncontrolled.
Resistance Management
Some Group 2 resistance reported. Use multiple MOAs. Monitor for poor control.
We will add more weeds to this tool soon. Tell us if it helps you in your field.