Tenacity Herbicide does not list English ivy on the product label, but it is labeled to kill ground ivy so we would not recommend applying it to any desirable ivy.
When you apply Tenacity Herbicide will depend on how you are using it. When using Tenacity as a post-emergent herbicide, you should spot treat target weeds when they are young and actively growing, which may be in spring, summer, or fall. Generally, you do not want to use any post-emergent herbicides when temperatures are over about 85 - 90 degrees since your desirable grass will be more sensitive and the target weeds will not be growing when it’s that hot. Tenacity should be used as a broadcast application pre-emergent when renovating lawns listed as tolerant on the product label. Since these are primarily cool-season lawns, this application is generally done in the fall.
Tenacity Herbicide does not list Poa Supina as a tolerable species on the product label so we cannot recommend using it for this purpose.
If the Tenacity Herbicide application had enough time to completely dry before the temperatures spiked to 93 degrres, there shouldn’t be any issues. It is recommended to apply Tenacity when temperatures are between 65 to 85 degrees so early morning or late evening applications may work best if temperatures above 85 degrees during the day are expected. If any yellowing or discoloration occurs, the turf should recover after a couple weeks.
There is no wait time after applying Tenacity Herbicide to re-seed unless you are re-seeding with fine fescue. For fine fescue, it is recommended that you wait at least 30 days after application to re-seed.
Tenacity is not labeled to control undesirable ornamental plants, although it may harm them if sprayed accidentally. You will need to remove physically all the parts of the iris - including the rhizomes in the soil – in order to prevent these plants from regrowing the following year. You can use a glyphosate product such as RoundUp QuikPro to kill the above ground plants, but you will need to remove the rhizomes after spraying. This article has easy-to-follow directions on this treatment, which is best done in the fall.
If applying Tenacity Herbicide as a pre-emergent you would want to apply after applying any top soil to other matter to the top of the soil to prevent weeds growing in the new soil
Tenacity Herbicide has been tested on both ine fescue (creeping red, chewings and hard) and tall fescue and found to be safe under trial conditions.
Products that have been mixed with water must be used within 24 hours after mixing. Please contact your Local Sanitation Dept for guidelines in your area on disposal of unused Tenacity Herbicide .
Tenacity Herbicide will damage poa annua turfgrass. Be sure to check your grass type to ensure that the product can be used on your lawn safely.
Before applying Tenacity you must wait until the newly germinated turf has been mowed two times or four weeks after emergence (whichever is longer) before making a postemergence application.
When Tenacity Herbicide is used for post-emergent control of weeds the weeds are sprayed directly. According to the product label, when used postemergence, susceptible weeds absorb Tenacity through foliar contact and soil absorption. The 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 postemergence weed control.
Spray foliage of target weeds with Tenacity Herbicide until wet but not until the point of runoff.
No, Tenacity Herbicide is not labeled for Horse's Tail (Equisetum arvense), so we would not recommend using this product for it.