Another POA killer?

7 years ago

Sorry but I'm a roll about POA and hope someone has some experience with Ortho Nutsedge Killer. Not so much for Nutsedge (which I also have, but too soon to worry now), but as you can see by the picture on the bottle, it claims to also kill POA ANNUA. The active ingredient is Sulfentrazone. So who knows what other name this chemical might go by ?,,,,,These companies have many names for the same thing... Does anyone have experience with this? thanks in advance !

Featured Answer

lawniac

7 years ago

https://repository.arizona.edu/bitstream/handle/10150/216353/az12463a6-2001.pdf?sequence=1&isAllowed=y

1.Applied to late winter season flowering Poa annua in overseeded bermudagrass turf, Sulfentrazone herbicide had low-level activity for both vegetative or seed head suppression.

2. The low rate of 0.125 lb. AI/A provided essentially no control/suppression while the 0.250 and 0.375 lbs. AI/A rates yielded 18%-26% control via seed head suppression.

3. This level of control lasted for about 35 days, then declined drastically.

4. Mefluidide applied once at the 0.125 lb. AI/A rate, induced temporary injury to the Poa annua, and then resulted in 91% mean seed head suppression. Repeat applications would needed to be made to promote extended seed head suppression.

5. Sulfentrazone does not appear to reduce/suppress Poa annua as a post emergence herbicide at rates and timings tested here.

So, it might kill a little bit of Poa, but not to where it would be useful for anything other than to put on the label as a marketing ploy.

Sort by:Oldest

Comments (9)

greenjean2
Original Author
7 years ago
Gotta love it....marketing to us unsuspecting lawn nerds ! thanks for sharing your research.
Related Professionals
Sebring Landscape Architects & Landscape Designers · Ashland Landscape Architects & Landscape Designers · Westminster Landscape Architects & Landscape Designers · Austin Landscape Architects & Landscape Designers · Edison Landscape Architects & Landscape Designers · London Landscape Architects & Landscape Designers · Tallahassee Landscape Contractors · Topeka Landscape Contractors · Florence Landscape Contractors · Worcester Landscape Contractors · Olean Landscape Contractors · Missoula Landscape Contractors · Rome Home Builders · Gloucester Home Builders · Pueblo Home Builders
gardengal48 (PNW Z8/9)
7 years ago
That was one isolated paper that published those results.....in Arizona. Various other sources DO recommend sulfentrazone for control of Poa annua as well as assorted broadleaved lawn weeds (in addition to the sedges) so may work differently in different locales. And sulfosulfuron may be more effective against the Poa, as well as addressing the sedges.

btw sulfentrazone is a chemical compound and doesn't go by any other chemical names although like most herbicides, it is sold under a variety of tradenames.
greenjean2 thanked gardengal48 (PNW Z8/9)
lawniac
7 years ago
Various other sources DO recommend sulfentrazone for control of Poa annua

I use sulfentrazone regularly for nutsedge control and it does absolutely nothing to control Poa.

I think the OP bought an older bottle, they took Poa A off the label quite a while back. The most current label makes no mention of Poa A control.

well as assorted broadleaved lawn weeds (in addition to the sedges) so may work differently in different locales

It's not a matter of working differently in different locales, sulfentrazone has always controlled a variety of broadleaf weeds in addition to sedges and they are (and have been) listed on the label.
greenjean2 thanked lawniac
greenjean2
Original Author
7 years ago
Lawniac...this bottle is from last year, so right you are ! I just checked on the Ortho website and they did indeed remove mention of Poa Annua from the label. Those buggers ! One thing I did notice is that it seems to turn the Poa more yellow so its easier to hunt down and either dig up or kill with glyphosate.....

I'm gonna submit another question about the right set of steps to rid my lawn of this stuff.....I'd love to get multiple inputs...stay tuned ! Thanks to all !
lawniac
7 years ago
Well, the answer is simple, I don't know that you need a separate question. You will need to apply pre-emergent before it germinates. Prodiamine works really well on Poa A.
greenjean2 thanked lawniac
greenjean2
Original Author
7 years ago
Is Prodiamine a granule or liquid? Is it something Mrs Homeowner can readily find locally under a brand name? or does it need to be acquired online?
lawniac
7 years ago
Check your local SiteOne, they should have a spreadable granular prodiamine.
greenjean2 thanked lawniac
reeljake
7 years ago
It kinda works on poa. I use sulfentrazone almost exclusively these days for all my weeds. Crabgrass, nutsedge, sandburs, poa, no matter which season they pop up. I would use a poa specific product if that were my most common weed, but its it's just a minor nuisance in my climate. Houston gets so hot it burns off
greenjean2 thanked reeljake