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Herbicide Summary - Tordon® 22K

Used to control annual and perennial broadleaf weeds, woody plants, and vines; primarily for conifer planting site preparation.
Updated:
March 1, 2024

Common Name: Picloram-24.4%

Formulation: Water-soluble liquid (potassium salt)

Signal Word: Caution

Toxicity: Practically nontoxic; oral LD (50): >5,000 mg/kg

Use Classification: Restricted use

Minimum Required Personal Protective Equipment: Long-sleeved shirt, long pants, shoes, socks, and waterproof gloves

Carriers: Water

Activity: Absorbed through foliage

Mode of Action: Concentrates in active growing tissue (meristems), causing uneven cell growth and division

Selectivity: Most grasses are resistant

Precautions: Affects nontarget plants at very low concentrations if allowed to drift off site; do not apply to sites with highly permeable soils and high water tables or to soils with sinkholes over limestone bedrock; groundwater contamination may result

Application Methods: Foliar spray

Manufacturer: Corteva

David R. Jackson
Former Extension Educator, Renewable Natural Resources
Pennsylvania State University