Syngenta announced that Tenacity herbicide received registration from the U.S. Environmental Protection Agency (EPA) for use on residential lawns. The selective pre- and post-emergence herbicide controls 46 broadleaf weeds and undesired grasses in most cool-season turf types.  In addition to weed control in established turf, Tenacity can be applied at seeding to reduce weed competition for improved seedling development. 

“Tenacity provides a unique tool for professional lawn care operators,” said Pat Willenbrock brand manager for Syngenta. “Not only does it deliver pre- and post-emergence control of tough broadleaf and grassy weeds, but it can also be used at seeding to ensure new lawns flourish instead of competing with weeds. This ability for selective renovation provides an outstanding up-sell opportunity over glyphosate or sod options and helps reduce profit-robbing customer call-backs. There simply is no other herbicide available today that does all that.”

Tenacity was granted Reduced Risk status by the EPA due to its active ingredient, mesotrione, which has favorable ecotoxicity and human health profiles, compared to many registered herbicides, reducing the herbicide load on the environment.  Its mode of action is novel among turf herbicides, and it fits well into IPM and resistance-management strategies. As Tenacity is not yet registered for use in all states, lawn care operators should check with their state or local extension service prior to buying or using this product.

Mesotrione is based on a compound produced by the bottlebrush plant (Callistemon citrinus). Discovered and developed by Syngenta, mesotrione provides systemic pre- and post-emergence control of numerous weeds including nimblewill, chickweed, clover and yellow nutsedge. Additionally, it is the only herbicide available that offers control of crabgrass both pre- and post-emergence (up to the fourth tiller).

Tenacity has been tested and proven acceptable for use on many turf species including: Kentucky bluegrass, centipedegrass, tall fescue, perennial ryegrass and fine fescue.

As with all pesticides, it is important to read and follow label instructions when using Tenacity. More information can be found at: