Prime Source Meso 4SC Select – Generic Tenacity

[TimmyG]

I sprayed my first application of Meso 4SC Select today to target primarily creeping bentgrass. It appears to be the first and only generic option to Tenacity (40% Mesotrione) and a total clone. An 8-oz bottle is currently available from Pestrong.com for $53.25 with free ship. It's about a $10 savings compared to Tenacity.

I saw it available last fall but only just now needed a new supply of Mesotrione. Except for a vague mention by agn015 last September, it surprises me that no one else has mentioned or asked about Meso 4SC yet. I'll be sold when I see bleaching in 7–10 days.

[SalemChiro]

Please post your results using this product compared with the original Tenacity. I just ordered the generic version but haven't used it yet.

[agn015]

I still have my eye on the generic version. I have a little bit of my authentic Tenacity left, but as soon as that is gone, I'll buy whichever one is less expensive.

[CreepyPurpleFescue]

Topramezone, found in RoundUp's "Crabgrass Destroyer" is similar to mesotrione. For about 30 bucks you get the ready-to-spray stuff, with an electric wand with multiple settings, etc.

[TimmyG]

Alas, creeping bentgrass is marginally tolerant to topramezone (Pylex), so mesotrione is the one for me. And while convenient, I hope you aren't suggesting that Roundup for Lawns Crabgrass Destroyer in that RTS package is an inexpensive option. The label states that the gallon only treats 1,000 sq ft. It would cost nearly $600 for a single broadcast application over my 1/2 acre or so of lawn. Yikes! Suddenly, Pylex (concentrated topramezone) doesn't seem so cost prohibitive. Used as a spot spray, the Roundup product may be a good choice for some. But to control nuisance grasses like creeping bentgrass (if it could) where you first need a broadcast application to highlight where it is, mesotrione is far away the less expensive option, generic or not.

[CreepyPurpleFescue]

Oh, sounds like you are on top of it.

I also have a big lawn (more or less the same size are yours), and also with creeping bentgrass invasion! The topramezone definitely bleaches the bentgrass, but whether or not it kills it I don't know because bentgrass is tenacious and aggressively grows back over dead areas.

I did do a lawn-wide broadcast of mesotrione (via solid granules in Scotts starter+), and honestly was disappointed with results. I know that's not the best method and has a different intended effect compared to liquid tenacity, but still it was pretty bad (oh it definitely turned anything not KBG/RG white as a blizzard, but really didn't pack much of a punch, didn't prevent weeds (as the bag said it would), didn't do anything beyond temporary bleaching to bentgrass, etc).

I'm just rambling... as for your thread, I hope your generic meso works as well as the tenacity

[TimmyG]

Alas, I am not able to report conclusively at this time on my success with using Meso 4SC instead of Tenacity. Now two weeks after the initial blanket spray at ~3.5 oz/acre, I am only seeing mild whitening, none of which is on suspected bentgrass patches. The likely reason? I had a momentary lapse in judgment and mixed in triclopyr with my mesotrione blanket app with the intention of simultaneously targeting miscellaneous other sparse weeds. Unfortunately, triclopyr is known to reduce the whitening effect of mesotrione, and I knew that. It just didn't cross my mind on that day (it did the day after), and I certainly would have left out the triclopyr had it occurred to me. Achieving good whitening from that first application is critical to highlighting the offending patches of bentgrass and allowing one to finish up with only spot spraying. I didn't have time this weekend to do a second blanket application, nor do I in the next couple days, so it is likely that I will have to throw in the towel on my attack on bentgrass this season.