Is 6 oz per acre too high? Would 4 be more reasonable? I'm just using it to hold back the weeds while new seedlings take hold.

Well but how do you know the sprayer is going to spray at a rate of 3 gallons per 4300 sq feet? I understand that's what you're targeting, but the spray volume may be such that you're going to spray the whole 3 gallons over only 2500 sq feet. You have to calibrate your sprayer and work your way from there.

I have applied and practiced a good amount, i can evenly walk a 4g fill over 4k sqft, i measure it off and walk through it. if i'm off, i make sure to exhaust the spray in only that 4k area and i do not extend but most times it has worked out well. however, there is a chance for it not being even but how would i prevent that other than trying to be consistent?

You really can't help it, just have to do the best you can to be consistent. But if you're used to doing 4 gallons over 4ksf, then I would do the 4 gallons of water with 0.6oz of Tenacity and spray that over 4ksf like your normally do. If you have a little left over do the other 300 sq feet.

If, and it's a huge if, you can get everything down perfectly evenly, that would be the correct math.

However, 5-8 oz is the total application over the course of the season. For herbicide purposes, you'll only need a fraction of that. 1/2 tsp per gallon is the standard amount to apply, to go over 1,000 square feet. That works out to 0.083 ounces per thousand square feet per application.

That's in the manual, about 2/3 of the way through.

While the pre-emergent section recommends about 4 oz per acre for optimal pre-emergent use, I've found that the herbicide level functions very well as a pre-M for about a month.

I've only had experience with pelletized siduron pre-m. Is spraying tenacity as effective as applying mesotrione pellets for pre-m control when overseeding an established lawn? Will enough spray reach to soil to be effective?

If I recall correctly Spray Tenacity directions as "Pre-M" indicate must be watered in with .15" water after application.

I found a spreadsheet a guy put out online and it jives with the number you guys are showing (.5 tsp per 1000 sqft). ill probably do 2 doses on two sections of lawn before i do the prodiamine and then there is a possibility of 3 doses to my back yard before get to doing the full kill for the reno. I don't think any of those would get me over the yearly max.

I have irrigation so i'll water it in and then i'll time it right at my FILs house to either apply before rain or just have him hand water it in.

If you do a reno in the fall, you will want to use Tenacity at seeding and a month later. It's more important then than now. So save at least two applications for the Reno.

Can you spray it one month after seeding (on new little seedlings?)

Yeah I think if I did two now at 4oz and two then, that would serve me well at get me to the yearly max

>>Can you spray it one month after seeding (on new little seedlings?)

Yes! They might white out (I'd recommend not using surfactant and watering it in immediately--and even then, the plants will pale out as Tenacity root absorbs perfectly well). They'll recover in two months or so.

So morph, I'm applying tenacity to all overseeded grass ATM. Surfactant or no?

For pre-emergent, don't bother. If you're applying it to existing weeds AND as a pre-m, yes.

Ok so if I'm coating the area now where the weeds haven't sprouted yet you'd suggest a straight application? I have the surfactant, is it an "insurance policy" if I do use it?

Surfactant is used to make your solution stick to leaves of plants you want to kill. If its a bare patch of ground, it wouldn't be needed. You use surfactant as additional "force multiplier" in Post-M applications.

Tru dat. The insurance policy isn't necessary when using it as a pre-M.

It won't hurt...but it's not necessary.

I put it down this round without any surfactant because there are minimal weeds sprouted (i tried to pull them all out). I think next round i'll use the surfactant as I assume there would be some weeds growing and id like to catch them before they drop more seeds!

Its raining today......between .4-.5" i know tenacity has to be watered in but any issue with the half inch or is that fine? Not like i'm going to stop it!

Half an inch to an inch isn't a problem at all (even 2", as long as it's not running off a lot) is no issue!