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Iron (present as FeHEDTA)

Herbicides whose active ingredient is FeHeDTA may be used to control common chickweed (Stellaria media)
Photo: Jardin botanique de Montréal (Édith Smeesters)
Stellaria media

The information below is intended only as a guide. Always read product labels carefully.

Product description

Herbicides whose active ingredient is iron (present as FeHEDTA) are made of chelated iron (FeHEDTA) obtained from a HEDTA acid treatment.

These herbicides are used to eliminate or repress undesirable broadleaved plants from the lawn.

They are sold in ready-to-use liquid form or in concentrated form to be diluted before vaporization.

Target plants

Herbicides whose active ingredient is FeHeDTA may be used to control undesirable plants such as:

  • Common dandelion (Taraxacum officinale)
  • Black medick (Medicago lupiluna)
  • Bull thistle (Cirsium vulgare)
  • Canada thistle (Cirsium arvense)
  • Common chickweed (Stellaria media)
  • Creeping buttercup (Ranunculus repens)
  • English plantain (Plantago lanceolata)
  • Common plantain (Plantago major)
  • Algae and moss

Caution: This pesticide kills white clover (Trifolium repens)

NB: The product label lists the plants on which the pesticide may be used, along with the target organisms. 

How it works

The excessive uptake of FeHEDTA by many broadleaved species leads to tissue necrosis and ultimately plant death. There is no clear explanation why grass is less sensitive than broadleaved plants. It is believed that the level of sensitivity to the product is linked to the absorption capacity of each plant group.

The first visible signs of elimination usually appear a few hours after application. Sensitive plants turn brown or black.


For best results, apply the treatment when weeds are in active growth.

For localized treatment, spray the undesirable plants until the foliage is completely soaked. Repeat every three to four weeks as needed, but do not apply more than four times per site per year.

Do not apply this product when:

  • Rain is expected 3 hours after application
  • The lawn is stressed by drought (watering before treatment is then necessary)
  • The temperature exceeds 30°C
  • The lawn contains bent grass (this type of grass is sensitive to the product).

Wait at least four weeks following the appearance of new grass before treating newly seeded areas.

Grass blades may darken after treatment. They will return to normal after a few days or a few weeks.


This product must not come into contact with ornamental plants, fruits and vegetables, as it can damage several broadleaved plant species. In case of contact, immediately rinse with water.

Wear gloves, long clothing, a mask and glasses when applying this product. Avoid contact with eyes, as this may cause an irritation. Avoid contact with skin and clothing. Do not walk on the site before the herbicide has dried.

Do not apply this product close to a body of water, watercourse or wetland. Moreover, avoid contaminating the water of these habitats and sewers by disposing of the excess pesticide or rinsing the application equipment there.

Keep this product out of the reach of children.

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