Discussion in 'Pesticide & Herbicide Application' started by richardcog, Nov 13, 2013.

1. ### richardcogLawnSite Memberfrom Brandon, MississippiPosts: 118

If i was going to apply 2 LB of a herbicide to a site. The herbicide is formulated as 60 WDG. How much of the product will be needed?

2. ### jsslawncareLawnSite Bronze Memberfrom North GeorgiaPosts: 1,674

What does 60 wdg mean?

3. ### SkipsterLawnSite Bronze Memberfrom Billings, MTPosts: 1,074

We'll need a little more info to give you the best answer. You're going to need to know the product application rate and your application spray volume. The ai load of the formulation (the 60 WDG part) isn't needed for this calculation.

The application rate is an amount of product per unit area (usually ounces or pounds per 1000 sq ft or per acre). Recommendation for this use rate can be found on the product label. Your application spray volume is how much water your sprayer is putting out per unit area. This is often expressed as gallons per 1000 sq ft or gallons per acre.

So, for example, if you need to apply a product at 2 pounds per acre and your sprayer is calibrated to deliver 50 gallons per acre, you will need to add 2 pounds of product for every 50 gallons.

To figure out how much product you'll need to buy, measure your area and multiply by the product rate. If you have a half-acre site and a 2 pound/acre application rate, you'll need 1 pound (0.5 acres * 2#/A) of product to cover the area.

This is a great learning opportunity here. I think many of us in the industry can use a brush-up in math.

4. ### CL&TLawnSite Senior Memberfrom New YorkPosts: 493

I posted a reply (albeit snotty) that disappeared inquiring about the OPs license status. My opinion is that if you aren't licensed, don't know how to read the label and interpret the information you have no business applying pesticides.

5. ### richardcogLawnSite Memberfrom Brandon, MississippiPosts: 118

This is a ? on my practice test. this is all it said. They said it will be on the test like this. so im just trying to find out how to come up with a answer

6. ### richardcogLawnSite Memberfrom Brandon, MississippiPosts: 118

wdg means- water- permissible granules

7. ### RigglePLCLawnSite Fanaticfrom Grand Rapids MIPosts: 12,218

Or maybe, Water Dispersable Granule. WDG.

That is a small granule that is not dusty, easy to pour, but disperses when added to water to form a suspension of powder in water. This is a common formulation for fungicides, insecticides and some herbicides. It is sometimes called a DG formulation.
Skip is right.
Normally, if the label says 2 lbs it will specify that the amount covers one acre. Add it to whatever amount of water your equipment applies to one acre.

60 WDG would normally mean a WDG formulation containing 60 percent active ingredient. If you need to calculate the rate on an AI, "Active Ingredient" basis...adding 2 lbs active ingredient, divide by the active ingredient, which is .60, so...2lbs/.6= the result would be 3.33 pounds.

Question does not mention if it is to be applied on an "Active Ingredient" bases or the usual straight from the bag on an as formulated basis. The question said "site", it leaves out how many acres you will cover, and how many gallons per acre your equipment applies. Also how big is the tank?

8. ### richardcogLawnSite Memberfrom Brandon, MississippiPosts: 118

I know that is why I was so confuse I hope this is not on the test that way

9. ### richardcogLawnSite Memberfrom Brandon, MississippiPosts: 118

Thanks you for the help

10. ### CL&TLawnSite Senior Memberfrom New YorkPosts: 493

Fair enough, my apologies.

Since all the information they give is 2lbs of herbicide applied to the site and the product is 60 WDG and they want to know how much product to apply they are looking for the AI rate.

"60" means that the product is 60% herbicide (active ingredient or AI) and the rest could be fert or something else, depending on what the product is. So you know you are going to have to apply more than 2lbs of product.

So if you have to apply 2lbs of AI to a given area how much 60 WDG product will you need? You divide the 2lbs by 60% (0.6) and you get 3.33lbs of product.

Last edited: Nov 14, 2013