There is not a specific amount of time you need to wait to apply your fertilizer after applying Quinclorac 75 DF. Since Quinclorac works best when it has at least 24 hours to dry after application, then waiting at least 1 day before watering or applying a liquid fertilizer would be advantageous.
No, quinclorac products are not labeled for use on St Augustine. This is a very sensitive turf type and quinclorac may harm it. Instead you can use a product like Image Kills Nutsedge or Atrazine for small lawns, or Blindside for larger areas.
Quinclorac 75 DF lists on the product label that centipede grass is susceptible to damage if applied so it would not be recommended.
Quinclorac 75 DF needs to time to be absorbed through the weeds and you do not want the weeds to be stressed from mowing or it will not be effectively absorbed. You need to apply at least 2 days before mowing or wait 2 days after application to mow.
Quinclorac 75 DF is a post-emergent herbicide, so the best time to apply it is when the target weeds are actively growing. If you are targeting crabgrass, then it is best to treat in late spring/early summer when the crabgrass is still small, or later in the summer or early fall when the grass has resumed growing again. You want to be cautious about broadcast applications of this or other post-emergent herbicides during the hottest parts of the summer: the desirable turf will be under more stress from the heat and the target weeds will not be growing much. You can broadcast or spot treat with Quinclorac at labeled application rates.
Quinclorac 75 DF is safe to use on bermuda as directed on the product label.
The amount of time you will need to wait to reseed after applying Quinclorac 75 DF will depend on the type of seed you are using. Please refer to the seeding chart on p. 11 of the product label for specific timing.
When using Quinclorac 75 DF you would want to use a methylated seed oil surfactant like Prime Source Duo Stick.
We would recommend to seed and then wait 28 days to apply Quinclorac 75 DF
When Quinclorac 75 DF is applied can vary depending on the target weed as directed on the product label. Retreatment intervals can be 14-21 days. Keep in mind that post-emergent herbicides will work best when the target weeds are young and actively growing. Quinclorac is only a post-emergent herbicide, so it doese not prevent any new weeds from germinating.
Quinclorac 75 DF can be tank mixed with pre-emergents such as Prodiamine as long as rates for each product are followed. We do recommend that you do a jar test to ensure proper mixing before adding to your tank, and also that you add a surfactant for the Quinclorac to be more effective
Quinclorac 75 DF should be applied when the ground is not frozen and rainfall/snow is not expected for more than 24 hrs. You want to treat when the weeds when they are actively growing for the best results. We recommend to make the application in the cooler times of the day also when temps are between 65-80 degrees.
You should be able to safely mix the Quinclorac 75 DF and a 2,4-D product to get a wider range of weed and weedy grass control with no issues. As with any chemical mixture, be sure to do a tank-mix test first to make sure no clumping or mixing issues occur and spot test a small area to be sure no undesirable effects occur from the mixture and use. Always follow the most restrictive label of the two for use and refer to each product label for complete instructions regarding tank mixing.
After applying Quinclorac 75 DF Herbicide crabgrass will first discolor and then over a long period of time start to breakdown. You will have discolored spots for some time unless you choose to remove the dead crabgrass physically.
Quinclorac 75 DF should not be applied to exposed feeder roots of trees, ornamentals or within the dripline of trees and other ornamental species.
If the Marathon turgrass you have is a Tall Fescue seed blend then yes, Quinclorac 75 DF Herbicide would be safe to apply as Tall Fescue is a tolerant turfgrass per the product label. For spot treatment of weeds, it is recommended to use a MSO surfactant for better adhesion and faster burndown of weeds.
Quinclorac 75 DF Herbicide comes included with a measuring device that should assist with the precise amount, if you do not have the measuring cup, you will need a scale to measure it as it is done by weight and not volume as a dry product. Please refer to the product label for application rates and instructions, and use as directed.
Quinclorac 75 DF should be used with a Methylated Seed Oil (MSO) surfactant such as Prime Source Duo Stick. Generally speaking, triclopyr does not require a surfactant and is normally applied in cooler temperatures whereas quinclorac is applied in warmer temperatures. Using triclopyr with an MSO may be too harsh on any desirable turfgrass. There is a specific window (time frame) these types of products could be applied if they were to be applied together for a situation labeled safe for that type of use. We would recommend contacting your local cooperative extension office for more information on the best timing to treat the specific weeds in your specific region.
The manufacturer of Quinclorac 75 DF Herbicide suggests not storing diluted solution for more than 24 hours to avoid losing efficacy.
Quinclorac 75 DF is used at the rate of 0.367 oz per 1000 sq ft when applied as a broadcast appliation or spot treatment in a minimum of 0.5 gallons of water. If you are just spot treating with a specific amount of water, for example 1 gallon, you would use the 1 tbsp per gallon of water. So if you are treating the entire lawn, you could use 1.25 oz in 4 gallons to treat the entire lawn.
