Spring Pre-em accuracy

[greenrebellion]

I'm thinking ahead to Spring because the approaching winter and increasingly cloudy days already has me depressed.

When I apply Pre-em, what I usually do is mow beforehand (wheels are 20" apart) which is perfect spacing for my backpack sprayer and gives me very accurate lines (I just spray on the wheel tracks).

I'll need to get a spring pre-em down early April and that will be well before it is time to mow, the ground will be really mush with all the snow cover I get that melts away and thus I'm not sure it would be good for me to drag a 500lb lawnmower over it. Further complicating things is the pre-em I use (Prodiamine) is yellow, so using tracking dye turns the mix green, which is less than ideal when spraying on grass.

Anyone have any tips for accurately applying pre-em in these conditions?

[JohnP]

LCN talks about using polarized glasses to be able to see the sprayed areas but I don’t know if it works.

I’ve seen some people use those little flags that utility companies use to mark “columns” as well. Just at the ends so you have a spot to look at and walk towards. You could pry put a few down the lane too to help guide. Easy to push in and inexpensive.

[ken-n-nancy]

When I apply Pre-em, what I usually do is mow beforehand (wheels are 20" apart) which is perfect spacing for my backpack sprayer and gives me very accurate lines (I just spray on the wheel tracks).

I do the same, too. It works really well, even without a tracker dye.

I'll need to get a spring pre-em down early April and that will be well before it is time to mow, the ground will be really mush with all the snow cover I get that melts away and thus I'm not sure it would be good for me to drag a 500lb lawnmower over it. Further complicating things is the pre-em I use (Prodiamine) is yellow, so using tracking dye turns the mix green, which is less than ideal when spraying on grass.

Anyone have any tips for accurately applying pre-em in these conditions?

Unless I'm missing something, you shouldn't need to be applying a pre-emergent until the ground has warmed up enough to no longer be "mush with all the snow cover I get that melts away." We have a similar amount of winter snow here, too, but I don't see forsythia bloom until after the snow has melted away and the ground has solidified enough to be mowable again. The Bewitched hadn't started growing much yet when I applied Prodiamine (0n May 10), but even the (slow) Bewitched showed mowing tracks well enough to apply pre-emergent. (The fine fescue, on the other hand, started growing a couple weeks earlier.)

[TimmyG]

Your mower has 20" wheel spacing and weighs 500 lbs? Que?

You should be mowing well before it's time to apply pre-M. If the established cool-season grass ain't growing, what exactly are you worried about germinating? Certainly not crabgrass.

[greenrebellion]

500lbs was an exageration but Forsythia blooms around here usually in early April, at which point the ground is still pretty wet. Guess I'll wait and see what transpires and use flags if the ground is too soft for an early mow.

[andy10917]

If the mower weighs X lbs when used in early April, does it weigh less than X when used in May or August? I'm not getting how the month of April and the mower weight affect things...

[greenrebellion]

If the mower weighs X lbs when used in early April, does it weigh less than X when used in May or August? I'm not getting how the month of April and the mower weight affect things...

Only reason I mentioned it was because the ground around here is particularly soft in April because we get a ton of snow coverage in the winter that takes a while to melt off and it leaves the ground super saturated in early Spring.

[73Chall]

I’m quite used to marching to the beat of a different drum and I guess pre-m is another example of that, with me at least ... I no longer wait until I see the forsythias bloom; I had mixed results when I did (biggest variable beyond my control being the bizarre, impossible to forecast micro-burst gully washers we get out of the mountains and which are famous for washing the most pains-taking app of pre-m (or anything else for that matter) away. So, years of trial and error - in the micro-clime I call home - sees me first putting down at 1/2 app rates and then often putting down my 2nd 1/2 app when the forsythias bloom. But, I use granules broadcast spread only ...

Anyway, in response to your (OP’s) last sentence in form of a question: is using granules via broadcast spreader out of the question? I mean, I guess you’re still left with the problem of “nice, tight rows” but, spreading should alleviate some of that, no?

Also, were it me, I’d just use enough blue marker dye that the yellow in the Pro-D simply did not matter ... I mean, marker dye is INEXPENSIVE, yes? Compared to tearing the mush turf up, marker dye is relatively cheap enough to mix it to the point it is so dark it ain’t green no mo!

Best o’ Success!

[greenrebellion]

Granular could work at a half rate application and maybe I follow up with a partial app of Prodiamine WDG later in the spring. Generally, I prefer liquid apps so I'd like to stick with liquid for as much as I can.

Does anyone know how Pre-em maximums work when applying different products? Obviously each individual product has a maximum annual application rate but I haven't found anything that would give an idea as to how to treat maximums when applying different ingredients (Dithiopyr/Prodiamine). I imagine that it isn't wise to apply the maximum rate of multiple different pre-em products.