How to Deal with Late Spring-Summer Mosquitoes In The Lawn

Can you all believe that May is nearly half over? It seems like just yesterday we were monitoring soil temps for early season crabgrass applications. Now I’m warning you about heat stress and telling you to prepare to water. I hope you are keeping your lawn journal updated! I enjoy doing mine with a nice Cigar.

Speaking of heat and watering, for those of you who have my pre-emergent guide, you should:

Cool Season Lawns - Kentucky Bluegrass, Fescue, Rye - it’s nearly time for your second pre-emergent application of the season and this one is dithiopyr. I do recommend the granular here because I have used the liquid concentrate and I can tell you: the scent is strong, very strong. Best to stick with the granular.

The reason we want dithiopyr here is because it does have some postemergence activity on crabgrass up to the 2-tiller stage. Applying this in early June as I recommend is just about the time some of those newborn crabgrass plants may start reaching out for sunlight.

If you are new here, and you have not applied any pre-emergent herbicides yet this year, you are NOT too late. Get the dithiopyr and apply it as soon as you can, water it in. Note: our primary target here is crabgrass. If you get the High Yield I linked above - the rate is 4lbs/1000 sq ft.

What about fall seeding?

Many of you are planning to seed your lawns in fall and are wondering if these pre-emergent applications will cause you issues. The answer is that they could but not likely if you aerate. I do recommend double or even triple pass aeration in conjunction with fall overseeding. Busting up the soil like that creates a great seed bed… and also destroys the pre-emergent. You’ll also be watering a lot (you have to water seed!) which will wash out anything remaining anyway.

Warm Season Lawns - St Augustine grass, Bermuda, Centipede, Zoysia - you guys are coming up on a choice. If you have major issues with kyllinga and sedges, then your best choice is Pennant Magnum. I realize that’s an expensive bottle of chemical, but it will go a long way. At the rates we apply, you will get 135,000 square feet from that one bottle. That’s more than 13 applications to a 10,000 square foot lawn.

Or $22 per application.

The reason I’m adamant about using Pennant Magnum is that it prevents doveweed, sandbur, signalgrass and of course crabgrass. These are all scourges to warm season lawns.

Additionally, it suppresses kyllinga and sedges which will continue to plague us all year long. I already applied my app over a month ago and I have almost no sedge at all after some touch up with Dismiss. In order to control sedges you need a strong pre-and-post emergent game.

Warm Season - Bahia Grass - you guys always give me sh*t because I ignore you and I’m truly sorry about that. I have nightmares over Bahia because of the giant seed heads that grow. When I was a kid my neighbor would pick them, bundle them together and chase me around my yard whipping me. He was a bully and he ruined this grass type for me; I’m scarred for life.

Anyway, I shouldn’t be taking it out on you folks - it’s not your fault you have this terrible, abusive grass type.

All joking aside, the other issue is that Bahia just doesn’t play nice with any other grass types and its chemical tolerances are also different. However, that’s not the case with pre-emergents. You can use Pennant Magnum or Dithiopyr and be just fine. So go get it, and water it in.

Late Spring-Summer: Mosquitos In The Lawn

One of the drawbacks (the only one) to having a thick lawn is the mosquito issue they foster. Back in NW Indiana, my thick tall fescue was a haven for mosquitos and made the lawn unuseable when left untreated.

I’ve got very similar issues with my St Augustinegrass here South Florida.

What can be done?

I really like this granular product from Bayer - To me, granular products are easier to apply. The other thing is, at least for me, I’ve always gotten better mosquito control with granular products. I think it’s due to the fact that for us homeowners, when we apply liquids, we are using pump sprayers that are very low volume. That essentially keeps the liquid insect control from penetrating into the thatch layer where the mosquitoes are breeding. With granular products, things seem to get deeper, faster. Either way, water the product in after application.

The other thing, if you apply that product at the higher rate of 3lbs/1000 sq ft - you will also get some decent grub prevention for at least 6 weeks or so, same for sod webworm. Lastly, you can also “band” it around your house as a perimeter pest control. Many uses, great product.

Liquid Alternative for Mosquitoes: However, if you insist on liquid, I also can appreciate that. You may already be doing an application of RGS or 0-0-2 Micro right now, liquid, and spiking in 1/2oz per gallon of Bifen insect control concentrate is very easy to do. This product, however, isn’t going to work on Chinch these days - but it’s great on Mosquitoes and very cheap overall. Apply every 3-4 weeks as needed, just watch label maximums. This will also control other nuisance pests like ants, fleas, and ticks.

Good Lawn Care Videos from around YouTube:

Jake The Lawn Kid applied Milorganite, RGS and talked about fixing the grade around his house. He also identifies a Quack Grass problem in his lawn and sets a strategy to get rid of it. Excellent video as always Jake! Click here to watch it.

Handy Dad TV did a video showing the latest Rachio Smart Controller. I have the Gen 1 and I love it. I use it to control my sprinklers like the fountain at the Bellagio. Anyway, he is also going to be giving one away so go check it out here.

Connor Ward found a giant grass water bubble in his lawn and he is actually excited about it. Nice shirt he is wearing too!

Grass Daddy did a nicely detailed video helping you identify Poa problems in the lawn.

With that, I hope you have a great week and be sure to get out and do some weeknight lawn work this week to get ahead on your weekend task list!

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