NC State Extension Publications

Problem

Herbicide injury from glyphosate: a non-selective, systemic herbicide.

Symptoms

  • Initially, new tissue chlorosis on most grasses and broadleaves.
  • Chlorosis progresses to tip necrosis in 5 to 10 days.
  • Necrosis of entire plant within 3 weeks.
  • Woody plants or glyphosate resistant weeds may re-sprout.
  • Re-sprouting tissue may be chlorotic, malformed, strap-shaped, witches broomed.
  • In woody perennial weeds, symptoms may re-occur up to 3 years after exposure.
witches broom, yellow stunted new growth

Fall applied glyphosate on knockout rose causes variable symptoms the following spring.

J. Neal  CC BY-NC-SA - 4.0

Knockout rose treatment.

Knockout rose, non-treated new growth on the left; treated on the right. Two weeks after treatment.

J. Neal  CC BY-NC-SA - 4.0

Glyphosate spray drift injury on rose, 2 weeks after treatment.

Glyphosate spray drift injury on rose, 2 weeks after treatment.

J. Neal  CC BY-NC-SA - 4.0

Non-treated rose. Photo taken same day as preceding photo.

Non-treated rose. Photo taken same day as preceding photo.

J. Neal  CC BY-NC-SA - 4.0

Glyphosate misapplication to rose.

Glyphosate misapplication to rose. About 3 weeks after treatment. Tip necrosis.

 CC BY-NC-SA - 4.0

Glyphosate spray drift, systemic injury to tomato.

Glyphosate spray drift, systemic injury to tomato, 5 days after treatment.

B. Lassiter  CC BY-NC-SA - 4.0

General chlorosis on new growth of grape.

General chlorosis on new growth of grape, 5 days after glyphosate spray drift.

B. Lassiter  CC BY-NC-SA - 4.0

Strawberry new growth is yellowed from glyphosate spray drift.

Strawberry new growth is yellowed from glyphosate spray drift, 21 days after treatment.

B. Lassiter  CC BY-NC-SA - 4.0

tip dieback and resprouting of glyphosate-resistant horseweed

Glyphosate resistant horseweed resprouts after glyphosate treatment damages the growing point.

J. Neal  CC BY-NC-SA - 4.0

Plant Entry and Symptom Expression

Foliar applied and symplastically translocated throughout the plant. Root absorption is rarely possible, only in sand or other soilless substrates. Not volatile. Crop injury is most likely as a result of misapplication or spray drift.

Similar Problems

Glyphosate injury may be confused with symptoms from:

  • Desiccation – loss of cell turgor pressure; salt accumulation.
  • Frost damage – non-selective injury to plant tops.
  • Paraquat (gramoxone) – rapid burn-down of all above ground tissue; regrowth possible.
  • ALS inhibitor herbicides may produce nearly identical chlorosis and tip die-back.
  • In woody plants, strap-shaped distorted foliage may resemble auxin herbicide damage, ALS inhibitor herbicides, or plant virus (such as rose rosette virus).

Herbicide Mode of Action Category

WSSA – 9

HRAC – G

Authors

Professor of Weed Science and Extension Specialist
Horticultural Science
Professor Emeritus
Cobleskill Univ.
Assistant Professor
Horticultural Science

Publication date: Sept. 10, 2015

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