[mrigney]

How do y'all decide when to spot spray your pre-emergent vs spray the whole yard? Is there some point that weed density crosses that changes what you do?

First year really taking care of the new sod. Didn't get pre-e down in the fall (did in the spring), so am having some weed pressure in the bermuda (and zoysia). I'll take some pictures when I get home. Not sure what kind of weed it is. It's in patches. Some places it's "bad" (by my standards at least), others not so much. At what point should I just spray the whole yard vs try to spot spray it all?

I'll take some pictures when I get home from work.

 

[Movingshrub]

Pre or post?

I've never spot sprayed pre-emergent. The whole yard gets it. For post-emergent, I've spot sprayed at times, and others, it's a blanket application mixed with the pre, resulting in a pre and post-em application at the same time.

 

[SCGrassMan]

You have weeds in Bermuda AND Zoysia, or you have Weeds and Zoysia in the bermuda? eg what are you trying to control? Just weeds, or weeds and bermuda / weeds and zoysia?

 

[w0lfe]

Man for the longest time I've been a spot sprayer every time, until relatively recently. There are soooo many weeds that you do not see due to their size, or ones you just completely overlook. So I feel it saves me more time to do my blanket spray in the spring once, in my case, the Bermuda can fill in thick enough to prevent many of the weeds from germinating. In addition, those weeds that you spray that you cannot see because they're small, are a lot easier to control than full grown mature weeds.

 

[Ecks from Tex]

How do y'all decide when to spot spray your pre-emergent vs spray the whole yard? Is there some point that weed density crosses that changes what you do?

First year really taking care of the new sod. Didn't get pre-e down in the fall (did in the spring), so am having some weed pressure in the bermuda (and zoysia). I'll take some pictures when I get home. Not sure what kind of weed it is. It's in patches. Some places it's "bad" (by my standards at least), others not so much. At what point should I just spray the whole yard vs try to spot spray it all?

I'll take some pictures when I get home from work.

Depends on the weed, but 8 times out of 10 I spot spray and would like to never have to do another blanket app. There's no good time to blanket apply and it nearly always stunts my st aug. But it's a necessary evil for a lawn still needing improvement.

For some I'll just let them go and focus on thickening up the grass to 4 inches, which will naturally kill out some of the weeds I have right now.

 

[mrigney]

@Movingshrub Definitely meant post...not sure why I typed pre. Brain getting ahead of fingers, I guess.

 

[Movingshrub]

@mrigney Thanks for clarifying. The only time I've done a blanket app was when I sprayed monument over the whole yard in October for control of poa.

As a comparison, I think Ware is spraying out his rye with a blanket app of MSM (whether he's done it or not yet I don't recall).

 

[Greendoc]

I am in the no spot spray camp. @w0lfe laid out why. I have another reason. Boom spray the entire lawn and not have to do it again for a long time vs walk around with a hand sprayer several months out of the year. Optics on walking around with what looks like a sprayer dressed in appropriate ppe several months out of the year are not good.

 

[pintail45]

How do y'all decide when to spot spray your pre-emergent vs spray the whole yard? Is there some point that weed density crosses that changes what you do?

First year really taking care of the new sod. Didn't get pre-e down in the fall (did in the spring), so am having some weed pressure in the bermuda (and zoysia). I'll take some pictures when I get home. Not sure what kind of weed it is. It's in patches. Some places it's "bad" (by my standards at least), others not so much. At what point should I just spray the whole yard vs try to spot spray it all?

I'll take some pictures when I get home from work.

Depends on the weed, but 8 times out of 10 I spot spray and would like to never have to do another blanket app. There's no good time to blanket apply and it nearly always stunts my st aug. But it's a necessary evil for a lawn still needing improvement.

For some I'll just let them go and focus on thickening up the grass to 4 inches, which will naturally kill out some of the weeds I have right now.

Golden Triangle in the house! I usually end up doing a combination of spot and blanket spraying due to all the Virginia buttonweed that Hurricane Ike so graciously delivered.

 

[Ecks from Tex]

How do y'all decide when to spot spray your pre-emergent vs spray the whole yard? Is there some point that weed density crosses that changes what you do?

First year really taking care of the new sod. Didn't get pre-e down in the fall (did in the spring), so am having some weed pressure in the bermuda (and zoysia). I'll take some pictures when I get home. Not sure what kind of weed it is. It's in patches. Some places it's "bad" (by my standards at least), others not so much. At what point should I just spray the whole yard vs try to spot spray it all?

I'll take some pictures when I get home from work.

Depends on the weed, but 8 times out of 10 I spot spray and would like to never have to do another blanket app. There's no good time to blanket apply and it nearly always stunts my st aug. But it's a necessary evil for a lawn still needing improvement.

For some I'll just let them go and focus on thickening up the grass to 4 inches, which will naturally kill out some of the weeds I have right now.

Golden Triangle in the house! I usually end up doing a combination of spot and blanket spraying due to all the Virginia buttonweed that Hurricane Ike so graciously delivered.

Woot woot! :bandit:

No joke about the Virginia buttonweed. Hurricane Harvey really screwed me. Thankfully no home flooding, but holy cow I lost over 250 sq ft of St Augustine due to Virginia Buttonweed in two months. It is just now filling back in and I'm just pulling the buttonweed as it appears. I may never kill it but I've already decided I'm just going to burn it this year if it gets out of control - not sure what else I can do since St Aug is my turf.

 

[pintail45]

I hear ya...my Dad lives in Winnie and got about 18 inches in his house. Thankfully the rest of my family in bmt was ok.

The bad thing about VB is it also spreads below ground. So, pulling it will keep it from dropping seedlings but won't kill it.

Over the years I've found a couple of products that will kill it but it usually comes back. Blindside is my favorite so far, it's expensive but works and doesn't kill SA when applied at label rates. Celsius also works but stunts the heck out of my SA. Image for Nutsedge works almost as good and is available at Lowes and HD for a reasonable price.

Whatever you use, spray a pre-emergent at the same time so it won't come back from seed.

 

[Ecks from Tex]

Thanks. I drenched the VB in Blindside last year and I swear it just grew stronger. Celsius is my next option but if it gets any warmer I'm just going to fight it by hand/with the torch.

I spray 4 rounds of pre-emergent each year (Feb - Prodiamine; April - Pennant Magnum; June - Dithiopyr; October - 2nd App of Prodiamine). My understanding is that none of these pre emergents is really rated for VB or does much to control it, but can suppress it if you apply high rates.

I think dismiss can be used as a pre emergent too

 

[Greendoc]

Just one application? For a weed like that one, it is a matter of repeated applications at a rate that the desirable grass can tolerate. Blindside is not something I care for. Too much Sulfentrazone(Dismiss) being applied at once and probably at a time when the lawn is not going to tolerate it very well. If and when I do apply Dismiss, it is at the lowest rate, starting in spring or fall and repeated until the maximum dose has been applied(12 oz per acre or else 11/2 teaspoon per 1000 sq ft). I apply mine as a 1/2 teaspoon per 1000 sq ft 3 times. Celsius at the medium rate applied twice is not hard on the St Augustine. The maximum rate is rather stressful especially in hot weather. I would start before it gets too hot.

 

[Ecks from Tex]

Two apps 21 days apart at max rate. Nothing happened it was pretty rough.

 

[Greendoc]

Another reason why I do not care for Blindside is that you cannot use effective surfactants with the product. I normally apply my Celsius or Metsulfuron Methyl with Methylated Seed Oil unless it is over 85 degrees. Anything containing Sulfentrazone such as Blindside is not to be combined with Methylated Seed Oil unless you are willing to accept scorching of the turf. I would not ever apply Sulfentrazone with Methylated Seed Oil to St Augustine. That is just too much for the St Augustine to tolerate. I will apply Celsius or straight MSM with the Methylated Seed Oil to St Augustine when conditions are right.

 

[pintail45]

Ecks, sounds like you're on top of things. I still have two tricks up my sleeve for VB: 1) Tenacity (mesotrione) + NIS; 2) Atrazine at max rate + MSO.

Greendoc, I'm curious what you think of the above battle plan. Would not spray at temps above 85.

 

[Greendoc]

How does your SA take the Tenacity? Last time I applied 4 oz Tenacity to SA, it turned white for a month but did not die. Because you can, a real torch of an application would be Tenacity at 4 oz per acre equivalent + a half dose of Atrazine applied with Methylated Seed Oil. Of course, test this out where your neighbors and wife will not see it. You see, when Atrazine or Simazine is combined with Tenacity, the effect of the Tenacity is amplified. Kills stuff dead, but I would evaluate how well the SA tolerates it before going end to end with it. I know that combination destroys Crabgrass, Goosegrass, and Poa.

 

[pintail45]

My SA has never seen mesotrione so I really don't know. Will have to try it on a test plot after I finish my bermuda control trials. That's a story for another thread but I'm currently experimenting with ethofumesate + half rate atrazine + MSO.

 

[Ecks from Tex]

Ecks, sounds like you're on top of things. I still have two tricks up my sleeve for VB: 1) Tenacity (mesotrione) + NIS; 2) Atrazine at max rate + MSO.

Greendoc, I'm curious what you think of the above battle plan. Would not spray at temps above 85.

Thanks, I'm going to look into those. I'm just worried it's going to hit my SA hard. Honestly if you're careful, keep a water hose nearby, I've seen some positive results from just burning the weed and letting the SA grow back in its place.