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Tenacity Herbicide is a systemic pre-emergent and post-emergent herbicide for the selective contact and residual control of weeds in turfgrasses. Tenacity can be used for weed control prior to or during seeding of certain turfgrasses during renovations. When applied as a pre-emergent, weeds absorb Tenacity during emergence from the soil. Dry conditions following application may reduce the pre-emergence activity. If rainfall (0.15 inches) has not occurred within 10 days after a pre-emergence application, activate with 0.15 inches of irrigation. When used as a post-emergent, Tenacity weed killer is absorbed by susceptible weeds through foliar contact and soil absorption. Foliage of treated weeds cease growth after application, then turn white (loss of chlorophyll) and death may take up to three weeks. A repeat application is required after two to three weeks for improved post-emergence weed control. A non-ionic surfactant should be added in post-emergence applications.
We also offer the Tenacity Herbicide Kit with Surfactant and Spray Indicator Dye which includes one 8 ounce bottle of Tenacity Herbicide, one 32 ounce bottle of Turf Mark Blue Spray Indicator Dye, and one 8 ounce bottle of Hi-Yield Spreader Sticker Non-Ionic Surfactant.
PLEASE NOTE:
Syngenta has recently updated its Tenacity packaging. You may get either the new packaging or the old packaging until all of the old packaging style has been depleted. There is no change to the product itself, only the exterior packaging.
Product Documents
Active Ingredient | Mesotrione 40% |
---|---|
Target pests |
Barnyardgrass, Carpetweed, Chickweed, Clover, Crabgrass (large & smooth), Dandelion, Foxtail, Goosegrass, Henbit, Yellow Nutsedge, Purslane, Thistle, Wild Carrot and others * See label for complete list |
For use in | Kentucky Bluegrass, Centipedegrass, Buffalograss, Tall Fescue, Perennial Ryegrass, Fine Fescue, St. Augustine Grass (grown for sod only) |
Application |
4 - 8 oz. per 30 gallons of water per acre * Use a Surfactant to Increase Effectiveness * See label for complete application instructions |
Formulation |
Professional Product Group 27 Herbicide |
NOT FOR SALE TO | AK, PR |
Shelf Life | 3-5 years from date of manufacture when properly stored. Keep out of direct sunlight and extreme temperatures |
Shipping Weight | 0.81 lbs |
Manufacturer | Syngenta (Mfg. Number: 46256) |
EPA Registration | 100-1267 |
Tenacity is a selective, systemic herbicide that features a new mode of action for pre- and post-emergence grass and broadleaf weed control in several cool- and warm-season turf species—like keeping bentgrass out of your rough. Tenacity can also be applied on established or newly seeded turf.
How was Tenacity herbicide discovered?
A Syngenta scientist in California noticed that there were fewer weeds growing under his bottlebrush (Callistemon citrinus) plant, far fewer than can be explained by shading alone. He concluded that the plant must be producing allelochemicals to suppress weed competition. Syngenta synthesized mesotrione based on the allelochemicals produced by the bottlebrush plant.
What is the mode of action of Tenacity herbicide?
Tenacity inhibits a plant enzyme called HPPD that is essential to photosynthesis and prevents formation of carotenoids in susceptible plant species. Without carotenoids, light energy and by-products of photosynthesis will destroy chlorophyll and cell membranes. This results in bleaching of leaves followed by necrosis and death of the plant.
How quickly does Tenacity work?
Once absorbed, Tenacity quickly translocates throughout the plant. Weed growth is suppressed soon after application, as photosynthesis is disrupted. Death of the plant usually occurs within two to three weeks.
What are some of the unique benefits of Tenacity herbicide?
Tenacity has pre- and post-emergence activity on 46 dicot and monocot weed species. It can selectively control perennial monocots such as bentgrass and nimblewill and annuals such as crabgrass and goosegrass in many turfgrass species. Tenacity can be applied at the seeding to prevent weed germination and allow the turfgrass species to establish without weed competition.
Can Tenacity be used to get bentgrass out of roughs and fairways?
Yes. Tenacity selectively controls bentgrass out of Kentucky bluegrass, perennial ryegrass, and tall fescue turf.
What does it mean that Tenacity was granted reduced-risk status by the EPA? Why did Tenacity earn this status?
Reduced-risk is an EPA designated registration status that accelerates the process for registration of certain new plant protection products. Tenacity received reduced-risk status by the EPA based on its unique mode of action, low use rates, and favorable toxicity and human health profiles, as compared to other herbicides currently on the market.
On which grasses has Tenacity been tested for use at or prior to seeding?
Tenacity is safe for use at or prior to seeding on Kentucky bluegrass, tall fescue, perennial ryegrass, and centipedegrass. Application at seeding can be made to fine fescue only if it is less than 20% of a seed mixture.
Are there any grasses on which you can't use Tenacity?
Tenacity is not recommended for use on zoysiagrass, hybrid or common bermudagrass, seashore paspalum, or kikuyugrass.
Can Tenacity be tank mixed with other herbicides?
Tenacity can be tank mixed with Barricade, dicamba, carfentrazone, triclorpyr, atrazine, simazine, s-metolachlor, bentazon, and several three-way phenoxy herbicides. Combinations can help turf managers broaden the weed control spectrum or improve the level of weed control over single-product applications.
How rainfast is Tenacity?
Tenacity is rainfast within several hours under normal rainfall conditions.
What other brands currently on the market offer a product similar to Tenacity?
There are currently no other herbicides like Tenacity for golf courses and sod farms registered for use or sale in the U.S. Tenacity will compete with multiple products from different classes of chemistry.
Tenacity Herbicide
By Frank on 05/07/2012
I had a lot of weed grasses in my yard and they were invasive and spreading over the whole yard. Tenacity targets weed grasses and kills them while leaving the rest of the yard in tact and that is exactly what it did. All of my weeds are dying. One thing you must note is that this herbicide needs to be watered after it dries on the plant so that the plant takes it in. It will not work if you just spray it on and don't get rain or water it for a couple of weeks. It's pricy but I know of no other chemical that will kill weed grasses and leave what you want, alone.
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630 of 659 people found this review helpful
A Miracle Herbicide!
By Margaret on 08/14/2012
I had a lawn that was completely taken over by bentgrass. I used round up on the lawn and put in an entire new lawn. All was well for a year or two. Then the the bentgrass came back in a few isolated areas. I would have to round them up at the end of the season and reseed. This went on for a number of years. When I learned about Tenacity I was thrilled and gave it a try. It works wonderfully! Yes it is pricy, however it beats having to round up the bentgrass, clear it out, put down more top soil and reseed. Try it...you won't be disappointed.
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398 of 414 people found this review helpful
Death of Nimblewill grass
By David on 10/02/2015
Great product! Does exactly what it advertises!
By Debi on 09/07/2012
My mom completely re-sodded front and back lawns and within 3 years it had been invaded by bentgrass. My new lawn was hydro-seeded 5 years ago in a new subdivision that used to be a golf course. Our methodology was to use Roundup in the fall (when the bent grass really seems to take off in growth) and then reseed the large killed off areas, hoping that the Roundup did a thorough job in killing the bentgrass. This becomes very tedious every year, not to mention the expense. We waited a few years for Tenacity to be available to the public and have both been having great results with the product. The good thing is that the remaining blades of good turf remain green in the kill zone. That gives me hope that I may not have to reseed, just wait for the good turf grass to fill in by itself. Our lawns are a combination kentucky blue and fescue blends. My only complaint is that the product is so concentrated and thick. The high concentration makes it even more critical to measure accurately! Not too crazy about the enclosed syringe measuring device. I feel it is too difficult to use and the potential to spill is high. I would love if there could be a more diluted Tenacity product to purchase for the average homeowner. That would make the product easier to measure, plus ensure a bit of wiggle room on the measurements?
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327 of 353 people found this review helpful
No more Crabgrass!!
By Rob on 08/23/2012
Is Tenacity available in Australia, Melbourne
Tenacity Herbicide is labeled for use on Tall Fescue, Kentucky Bluegrass, Centipedegrass, Buffalograss, Perennial Ryegrass, Fine Fescue, St. Augustine Grass. Other species of grass such as Bentgrass, Poa annua, kikuyugrass, zoysiagrass, seashore paspalum and bermudagrass are sensitive to Tenacity applications and damage may occur. According to the product label - Residential Lawn Applications: Unless renovating and/or re-seeding the home lawn, avoid broadcast applications of Tenacity for pre and post-emergence weed control because undesirable whitening of some turfgrasses may occur.
We do not ship to Australia and we are not sure if the manufacturer offers Tenacity in Australia. You can contact the manufacturer, Syngenta, to inquire about availability 866-796-4368.
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102 of 113 people found this answer helpful
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56 of 58 people found this answer helpful
the sprayed areas are turning white. Should I do another application at this time. The "bad" weed is hanging in there and I want to totally get rid of it befor winter. Thanks
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25 of 29 people found this answer helpful
My personal lawn. Was hydroseeded and slowly has been invaded with crabgrass and other grassy weeds.
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0 of 3 people found this answer helpful
I'm looking for a product that will kill Zoysia grass.
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110 of 123 people found this answer helpful
I know quackgrass is not specifically mentioned on the product label, but I have read some unscientific research saying it does control and eliminate quackgrass with repeated applications.
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10 of 14 people found this answer helpful
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6 of 7 people found this answer helpful
Every year i have problem with nutsedge weed. Can you suggest which pre- emergent is best to use.
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50 of 55 people found this answer helpful
I heard the product stays active even after composting and may harm my garden plants.
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188 of 203 people found this answer helpful
Tenacity Herbicide
Rating: 4.3 (615 Reviews / 662 Q&A)