This is directly off of the product label:
Apply 0.07-0.14 oz/1000 sq. ft. (3-6 oz./A) along with 0.25% v/v (1/2 pt./25 gals.) of a nonionic surfactant. Application should be made every 28 days when the grass weeds are actively growing. The higher rates may result in temporary discolorization of the desirable turf with recovery in 10-14 days. Do not apply to desirable turf which is under stress. For best results, make applications in spring and fall and avoid treatments during July and August.
Complete control of undesirable grass may take 1-2 growing seasons.
We also recommend calling your local county extension office as they usually know the optimum times for spraying lawns in your area.
The Fusilade II instruction label does not list St. Augustine grass, so we are not sure of the answer to your question. We would like you to direct your question to Syngenta, the manufacturer of Fusilade, as they are the true experts on their own product and can better answer your question. You can reach them at 1-866-SYNGENTA.
Updated Jan 2025:Fusilade is not labeled to be used on St Augustine for bermuda grass control when tank mixed with Recognition Herbicide. Following these instructions Recognition Herbicide 2(ee) Supplemental Label-St. Augustine
Bermuda would be considered a grassy weed, so you need a product that is geared towards grassy weeds and not broadleaf weeds. We want to be clear that bermuda can be suppressed, but it is VERY difficult to kill completely. It will take multiple treatments to finally kill it. But Fusilade II is usually the go to product for this issue.
This is directly off of the product label:
Apply 0.07-0.14 oz/1000 sq. ft. (3-6 oz./A) along with 0.25% v/v (1/2 pt./25 gals.) of a nonionic surfactant. Application should be made every 28 days when the grass weeds are actively growing. The higher rates may result in temporary discolorization of the desirable turf with recovery in 10-14 days. Do not apply to desirable turf which is under stress. For best results, make applications in spring and fall and avoid treatments during July and August.
Complete control of undesirable grass may take 1-2 growing seasons.
We also recommend calling your local county extension office as they usually know the optimum times for spraying lawns in your area.
The other option for you is to spray glyphosate product such as Gly Pho-Sel Pro or Ranger Pro on the bermuda when it is green in early August, wait three weeks to see if any bermuda survives and spray again by early September if needed and then re-seed the spots with fescue in mid-September.
Apply 0.07-0.14 oz/1000 sq. ft. (3-6 oz./A) along with 0.25% v/v (1/2 pt./25 gals.) of a nonionic surfactant. Application should be made every 28 days when the grass weeds are actively growing. The higher rates may result in temporary discoloration of the desirable turf with recovery in 10-14 days. Do not apply to desirable turf which is under stress. For best results, make applications in spring and fall and avoid treatments during July and August.
Complete control of undesirable grass may take 1-2 growing seasons.
Keep in mind for herbicides the amount of water is not important. What is important is getting the correct amount of product, over the correct amount of area. Mark off 1000 sq/ft and fill your sprayer tank with only water. Spray as if you were covering the area with the herbicide. However many gallons it takes you to cover that area is how many gallons to mix the product with. Everyone's walking speed and how heavily they spray is different, which is why whether you use 2 gallons or 8 gallons of water to cover 1000 sq/ft, you are correct.
Fusilade II Herbicide will not treat dandelion and chickweed as these are broadleaf weeds and it is only designed to control grassy weeds.
Fusilade II is not specifically labeled for peanut ground cover. We recommend contacting Syngenta 866 796 4368 to verify Fusilade II will be great fit for you.