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jtrice11
08-25-2005, 11:14 AM
Here in Minnesota if you are going to put down a fall application of Pre emergent what is the best time?

GreenUtah
08-25-2005, 11:57 AM
Regardless of the area, you need to decide what your target of control is, when it's germination time will be and how long the effective window for your pre-emergent will be. Under most conditions, at common rates, most pre-emergents have an effective window of 90-120 days. If your target is crabgrass that will germinate next June, applying 7 months prior will do what? If you have a different target in mind, just work backwards with your effective window and you'll have your answer. Pre-emergent is too expensive to waste.

Pro Lawn LLC
08-25-2005, 12:00 PM
I don't know about pre-emerge for the north, but if you base these types of applications on soil temps. you won't go wrong. For example - figure out at what soil temperature your target weeds germinate and just make sure you have your pre-emerge out slighty before the temp reaches that point. Best of luck.

Grassmechanic
08-25-2005, 02:39 PM
Actually, MSU did a study on fall applications of Pre-emergents. Dimension did very good on the test for crabgrass control the following season. This was done on cool season turf.

wriken
08-25-2005, 04:41 PM
Actually, MSU did a study on fall applications of Pre-emergents. Dimension did very good on the test for crabgrass control the following season. This was done on cool season turf.

Wonder when they put it down in the fall, also wondering when the soil reaches, what is it for crab, 55 degrees? I'm thinking of putting down pre, this fall if I can find out when.

GreenUtah
08-25-2005, 04:51 PM
Actually, MSU did a study on fall applications of Pre-emergents. Dimension did very good on the test for crabgrass control the following season. This was done on cool season turf.

But what were the soil conditions, density of the stand, fertilization schedule, available moisture and the window of when the soil heated up the next spring for cg germination? Did it perform the same as if it had been applied in the spring? What window if effectiveness does Dimension claim? Those are a few of the questions I would want answers to before gambling with my customer base that provides for my family and my employees families. But hey, that's me. I'm an agronomic conservative..lol

teeca
08-25-2005, 05:44 PM
is there a reason your putting down pre-m in the fall Vs. in the spring? being your even farther north then me in Indiana, why would you wast the money in the fall w/ pre-m. when you could put down a 46-0-0 to help the grass w/ storing the carb's it needs for the winter, then apply pre-m in the spring. i think you would be better off doing a weed spray in the fall to kill the winter annuals, this has been proven time and again to be the most effective time to control weeds.

wriken
08-25-2005, 08:15 PM
[QUOTE=teeca]is there a reason your putting down pre-m in the fall Vs. in the spring? being your even farther north then me in Indiana, why would you wast the money in the fall w/ pre-m. when you could put down a 46-0-0 to help the grass w/ storing the carb's it needs for the winter, then apply pre-m in the spring. i think you would be better off doing a weed spray in the fall to kill the winter annuals, this has been proven time and again to be the most effective time to control weeds.[/QUOT


I've been hearing some people doing this, I never have, but MSU apparently did a study on this, I know there big in turf. Maybe if you could find the right window to apply it, it would work, I probably will put it down in early spring though.

teeca
08-25-2005, 10:32 PM
purdue univ. is where i learned this. they have done all kinds of studies on when to spray, and say fall gives the best results hands down, of course you will still need to spray the dandy's in the spring though. the problem i have with fall pre-m's, other then the HIGH cost of product, is that alot of people overseed in the fall, nothing worse then killing $50+ worth of seed. i apply pre-e in the spring at 1/2 rate on round 1 (granular), then the other 1/2 on round 2 along w/ weed and fert (liquid). i used dimension only (insted of pendulum) for the first time this year and have to say it kicked a** ! with pendulum i had good coverage on crabgrass, but fox tail was a problem, with dimension, not a sign of any yet!! (knock on wood)

stumper1620
08-25-2005, 10:45 PM
[QUOTE=teeca]is there a reason your putting down pre-m in the fall Vs. in the spring? being your even farther north then me in Indiana, why would you wast the money in the fall w/ pre-m. when you could put down a 46-0-0 to help the grass w/ storing the carb's it needs for the winter, then apply pre-m in the spring. i think you would be better off doing a weed spray in the fall to kill the winter annuals, this has been proven time and again to be the most effective time to control weeds.[/QUOT


I've been hearing some people doing this, I never have, but MSU apparently did a study on this, I know there big in turf. Maybe if you could find the right window to apply it, it would work, I probably will put it down in early spring though.
MSU is big on pre-m in the fall for turf that has blue grass problems. I've never heard anything from them about spring crab other than spring app of pre-m.

stumper1620
08-25-2005, 10:49 PM
purdue univ. is where i learned this. they have done all kinds of studies on when to spray, and say fall gives the best results hands down, of course you will still need to spray the dandy's in the spring though. the problem i have with fall pre-m's, other then the HIGH cost of product, is that alot of people overseed in the fall, nothing worse then killing $50+ worth of seed. i apply pre-e in the spring at 1/2 rate on round 1 (granular), then the other 1/2 on round 2 along w/ weed and fert (liquid). i used dimension only (insted of pendulum) for the first time this year and have to say it kicked a** ! with pendulum i had good coverage on crabgrass, but fox tail was a problem, with dimension, not a sign of any yet!! (knock on wood)
I agree, kill the weeds, aerate, over seed, fert, pre-m in the spring.

Grassmechanic
08-26-2005, 09:45 AM
But what were the soil conditions, density of the stand, fertilization schedule, available moisture and the window of when the soil heated up the next spring for cg germination? Did it perform the same as if it had been applied in the spring? What window if effectiveness does Dimension claim? Those are a few of the questions I would want answers to before gambling with my customer base that provides for my family and my employees families. But hey, that's me. I'm an agronomic conservative..lol
I'll dig out the info. that I have on the study this winter, you may have to remind me, LOL. When MSU does a study, it is very thorough, and many, if not all, of your questions are answered. From my recollection, Dimension was quite impressive as a fall crabgrass control for the following spring.

ProLawns
08-26-2005, 03:58 PM
In our zone crabgrass germinates from may through august. How can applying pre-em in the fall cover this?

Olylawnboy
08-27-2005, 10:02 PM
Hey guys, I'm wondering, your talking about pre-em in turf right? So what is your target? Unwanted grasses or broadleaf weeds? or even both? Thanks....Oly

ProLawns
08-28-2005, 08:29 PM
Hey guys, I'm wondering, your talking about pre-em in turf right? So what is your target? Unwanted grasses or broadleaf weeds? or even both? Thanks....Oly
I target crabgrass in the spring and sometimes poa annua in the fall with the pre-em but it's nice to know that i'm getting some broad-leaf control as a bonus.

Grassmechanic
08-29-2005, 09:58 AM
Prolawns - the fall application study at MSU was done on cool season turf. I would suspect that a different study would be needed for turf in your area.

Olylawnboy - the target weed was crabgrass. There may have been some broadleaf control as well, I can't remember.

teeca
08-29-2005, 06:44 PM
want to target broadleaf weeds with pre-m? wow! granted they are effective on certin broadleaf weeds, but you will need to spen BIG MONEY if your planing on nailing them, were talking somthing like gallary, and tank mixing that will bankrupt you in a hurry!

Grassmechanic
08-30-2005, 05:29 AM
want to target broadleaf weeds with pre-m? wow! granted they are effective on certin broadleaf weeds, but you will need to spen BIG MONEY if your planing on nailing them, were talking somthing like gallary, and tank mixing that will bankrupt you in a hurry!
You need to slow down and re-read my post. I said the TARGET weed was CG. There MAY have been broadleaf control as well. :dizzy: Some broadleaf control with Dimension is a little bonus that you can get. :D

turf hokie
08-30-2005, 08:03 AM
When I use pre-emergent as a winterizer, my only target is Poa Annua. Any other control is a bonus. And yes it is an additional charge. Cost is around 40% more for the pre-emergent vs. straight winterizer.

Just my 2 cents.

Mscotrid
08-30-2005, 05:48 PM
Apply Gallery DF in the fall for superior annual grass and broadleaf control. Problem you might have is if you lose the customwer over the winter and the new service next year gets all the credit for your efforts.

Gallery will control winter weeds Henbit, Chickweed. Gallery is also the only Pre-E that I'm aware of that has Dandy's on the label. But you need to start applying by end of September for control to be effective.

LonniesLawns
08-30-2005, 09:41 PM
Preemergents in the Fall do not break down the same as in the SPring because of soil temps since preemergence herbicides are degraded in the environment through their gradual breakdown by microbial organisms

A beenfit of doing pre-emergent inthe fall is most pre-emergents are available in high nitrogen forulas that I don't like to put down int he spring, but are perfect in the Fall.

I will be using barricade this year and expect season long control next year.

GreenUtah
08-31-2005, 05:56 PM
So I suppose that winter moisture, soil type, dormancy, UV breakdown, etc all have absolutely nothing to do with anything when it comes to how long your product can stay in the active profile? Cool! Now if I could just get grass to stop growing so that mowers can stop picking up and shattering my prills, mayeb I CAN start doing magic wand treatments!

FINN
08-31-2005, 09:39 PM
I agree, kill the weeds, aerate, over seed, fert, pre-m in the spring.


Ok.... but........how do you work your seeding around the weed control? I know some guys will say its one or the other you can't have it both ways. The residual from wc will affect seed germination beyond what the label says.

stumper1620
08-31-2005, 09:47 PM
Ok.... but........how do you work your seeding around the weed control? I know some guys will say its one or the other you can't have it both ways. The residual from wc will affect seed germination beyond what the label says.
weed control should be down by now, so aerate, if you are concerned about residual, drag mat the plugs, then overseed or slit seed. I myself drag my plugs anyway, customers like it better that way, I figure I get a good enough germination it does not concern me.
Crab is seeding like crazy around here now so if it aint been killed then don't bother its done for the year anyway, just be sure to get pre-m down early in the spring.

NattyLawn
08-31-2005, 09:50 PM
weed control should be down by now, so aerate, if you are concerned about residual, drag mat the plugs, then overseed or slit seed. I myself drag my plugs anyway, customers like it better that way, I figure I get a good enough germination it does not concern me.

Hmmm....Your fall weed controls are done by now?

stumper1620
08-31-2005, 09:54 PM
Hmmm....Your fall weed controls are done by now?
what I want done before aeration & overseeding. yes.

FINN
08-31-2005, 10:05 PM
Stumper,

I was thinking the same as Natty. We are in the same area. Not much rain here. I don't have enough soil moisture right now to do all the weed control work I have where aerate and overseed is scheduled. I am thinking I might go in with QuickSilver and "knock em down" but not "out" so I can get the seed down. Or I will pick one over the other depending on situation.

stumper1620
08-31-2005, 10:31 PM
Stumper,

I was thinking the same as Natty. We are in the same area. Not much rain here. I don't have enough soil moisture right now to do all the weed control work I have where aerate and overseed is scheduled. I am thinking I might go in with QuickSilver and "knock em down" but not "out" so I can get the seed down. Or I will pick one over the other depending on situation.
this past week has been dry but the 2 weeks before that had rain spaced just about perfect to give a little window. results were'nt perfect but did have enough to get what needs doing.

LonniesLawns
08-31-2005, 11:04 PM
Well, of course on lawns that are being seeded they will get no preemergent and jsut get post-em treatment next spring.

Very few existing customers get overseeding