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Herbicide Summary - Spyder®

Controls many annual and perennial grasses and broadleaf weeds; used in the site preparation and release of both conifers and hardwoods.
Updated:
January 3, 2023

Common Name: Sulfometuron methyl-75%

Formulation: Dispersible solid granule

Signal Word: Caution

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

Use Classification: General use

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

Carriers: Water

Activity: Absorbed through foliage or root uptake

Mode of Action: Inhibits synthesis of key amino acids only found in plats by stopping growth in growing tips of both roots and shoots; has both pre- and postemergence activity

Selectivity: Many coniferous and hardwood species are resistant

Precautions: Causes moderate eye irritation; application over trees suffering a loss of vigor or following bud break may injure or kill those trees

Application Methods: Foliar spray, preemergence soil applications

Manufacturer: Nufarm

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