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blue bull
09-23-2005, 11:03 PM
I have been applying Dimension in Feb and March for control of crab grass. Many lawns have excessive break through that started showing up in July. How many times do you guys apply Pre M and when? Located in transition zone in North Carolina. Tall Fescue!

Mscotrid
09-24-2005, 12:52 PM
Let me first state that I'm not an expert in Carolina turf or climate. With that being said, my experience in the transition zone would have your applications too early for season long control.

You didn't metion rates of AI applied. Get a little bit more explicit on rates of application and we might be able to offer a better answer. I'm a big believer of using the highest label rate on all products I use. Spend a little up front can save you thousands is lost customers and service calls.

mcambrose
09-24-2005, 11:42 PM
I'm in north Alabama, so our climates may be similar. When I use Dimension, I put it out later than other chemicals because it has some activitiy on small crabgrass. I put my first application out in early april and my second at the end of May. You just put it out too early. You may prefer mid march and mid may.

ThreeWide
09-25-2005, 10:48 AM
When applying in March, you will need enough AI to provide nearly 6 months control. With Fescue, you want your pre-emergent to expire by the end of August in your area. This will give you the opportunity to overseed in September.

This is why so many people criticize pre-emergents in general, because knowing the application rate is critical. You need to understand exactly how long your weed prevention window needs to be when applying.

Dimension is sold in several different percentages of AI, such as 0.10, 0.15, and 0.21 percent. The app rate depends on the AI you purchase.

blue bull
09-28-2005, 06:52 AM
A.I. was .15% and application rate was split. Split applications at 2 lbs per thousand. Crab Grass is very visible here in late April and early May. Most guys put it out in Feb and March.

ThreeWide
09-28-2005, 08:34 AM
Using that rate, I can see why you might have problems.

You need 5 to 7 lbs of that particular product per thousand to realize 5 months of control.

Mscotrid
09-28-2005, 10:58 AM
A.I. was .15% and application rate was split. Split applications at 2 lbs per thousand. Crab Grass is very visible here in late April and early May. Most guys put it out in Feb and March.

Your using Dimension with a .15 load doing a split app. Not sure what you meant by 2lbs per thousand, that would make you on the ground ai almost unmeasurable.

.15 applied @ .25 load would require 167 pounds per acre would be 3.83 lbs per 1000. The .25 is the high end of the label, with crabgrass visible in late April why not delay your apps till end of March considering Dimension has up to the third tiller stage effectiveness? I've also added liquid Dimension to my spray tank and banded the edges with positive results.

Above all recommend your customers seed on a annual basis...

blue bull
09-29-2005, 08:22 PM
I put 2lbs A.I. per 1000 square feet. I now believe that I should have done the same in the April, May time frame. The bag says that about 4lbs per thousand of A.I. gets better results if put it down twice. It is evident that I did something wrong. The bag also says 3-5 months protection. That is a big window. What am I missing?

Mscotrid
09-30-2005, 10:13 AM
I put 2lbs A.I. per 1000 square feet. I now believe that I should have done the same in the April, May time frame. The bag says that about 4lbs per thousand of A.I. gets better results if put it down twice. It is evident that I did something wrong. The bag also says 3-5 months protection. That is a big window. What am I missing?

Blue,

I think you might be confused about Dimension and Active Ingredient (ai). There is noway you put down 2lbs ai of Dimension using a .15 load...Let alone doing a split app of another 2lbs ai. If you did you exceeded the label rate 8x. I would recommend you visit with your vendor and have the Dimension label explained to you with a little more clarity.

If you were to go 2lb ai with a .15 load you would have to apply 1,333 lbs of actual product per acre. Thats 30lbs per 1000, is that what you did?????

ThreeWide
09-30-2005, 10:35 AM
I gather that he applied 2lbs of product per M.

That being the case, he applied it at 1/2 the rate necessary for his objective. It should have went out at 4lbs or so. This explains the poor results.

Mscotrid
09-30-2005, 01:28 PM
I gather that he applied 2lbs of product per M.

That being the case, he applied it at 1/2 the rate necessary for his objective. It should have went out at 4lbs or so. This explains the poor results.

Turf,

On paper your correct, by prill count on the ground his app would be to sparse for any actual AI measurement.

marko
09-30-2005, 06:29 PM
I use to apply the first 2 apps with PreM if no overseeding was to occur. You can get away with your first app. when ground temps dictate, then more or less spot treat any known problem areas on your second app. That way can sell late spring aeration/overseeding.