Herbicides are a lot different than other concentrated products and can be hard to understand at first. The application rate depends on the the type of turf you have and how quickly you apply the product. You will need to read the product label to determine the correct usage rate for your needs (you did not give us any information about the type of lawn, region or application program you will be using so we cannot give you exact rates). The amount of water used to apply Dimension herbicide is not critical, but should be sufficient for uniform coverage of the target area. Calibrate by determining the volume of water required to treat 1,000 square feet. Use this calibration volume to determine the amount of water and Dimension herbicide needed to treat the target area (see the following calibration example). Note: Sprayer calibration (volume of spray needed to treat 1,000 square feet) will vary with each individual operator.
Steps in Calibration:
1. Mark an area of 1,000 square feet (i.e. 20 by 50 feet or 25 by 40 feet).
2. Place the sprayer on a level surface and add water noting the final level of water in the spray tank.
3. Spray the marked area with a sufficient volume of water to provide uniform coverage. Refill the sprayer to the same level as before measuring the amount of water added. The measured water added to the sprayer is the volume needed to cover 1,000 square feet.
4. Determine the application rate (0.55 - .73 fl. oz./1,000 sq. ft.) for Dimension from the Recommendations section of this label.
5. To each volume of water used as measured in step 3, add the amount of Dimension as determined in step 4.
Example: If the sprayer uses 1 gallons of water to cover 1,000 square feet and the desired application rate of Dimension is .55 fluid oz./1,000 square feet, then you would add .55 fluid ounces of Dimension to every 1 gallon of water to be used."
Dimension 2EW is labeled to control poa annua (annual bluegrass) before it emerges and should do a good job when applied at the right time. Please refer to the product label for complete instructions. If you are already dealing with Poa Annua, you will need to use a post-emergent, and we do carry several. Which you choose depends on your grass type. Certainty is a good choice, but please refer to the label to ensure it can be used on your lawn type.
Dimension 2EW Herbicide is going to be the best pre emergent product when controlling crabgrass. It is labeled to be used in Fescue lawns and can even be applied at a ratio to work as a post emergent.You will use .28-.73 fl oz. per 1000 sq. feet or .75-2 pints per acre. For your 2.5 acre property, 1.875-5 pints will be used to cover the entire area. Please read label for further instruction.
SnapShot 2.5 TG is not labeled to be used on lawns at all and would not be recommended. Dimension 2EW is our most popular pre-emergent herbicide for both grassy and broadleaf weeds and can be used on both St. Augustine and Centipede lawns. For Southern zones like FL, you would do a fall application by Oct 1st and for spring you would do a second application between February and March 15th at the latest. Re-applications and timing will depend specifically on what program you choose to use. Please review page 4 of the product label to determine the program that will best suit your needs. Tenacity or Atrazine would be good post emergent herbicides for your lawn type.