# Crabgrass Invasion!



## newlawndude (Jul 22, 2018)

Hi there, new guy here starting this never ending journey to have the best lawn on the street. But for now I have the best garden salad inon the street. I have the same battle most of you have with Crabgrass. I would say the year season started with a 15% coverage of crabgrass on my KBG. Since I started doing MIlo (in Apr and in July) with regular irrigation the crabgrass has taken off, I'm almost at 30% !!!. I started using Quinclorac (that' how is spelled?) and is barely doing an effect, it yellows and turns purple but it does not seems to die.

My major obstacle that I have to battle this thing is that My lawn sits next to conservation land, and I'm afraid using any chemicals might get me into trouble if big brother finds out. Specially Dimension.

I've heard that Corn meal is a great organic pre-emergent but I've also read that you might not get a good bang for your buck (I've read somewhere here that usually the rate is 20 lbs per 1k) and that it attracts rodents. Thinking like kind of a crazy guy, maybe silly, but we all know that crabgrass dies off at first frost, would it be reasonable to lay down a layer of dry ice over the dammed thing to see if it dies off? It will for cold burn for sure bu what about the seeds.

Apologies for the crazy idea but I'm desperate. Any advise?


----------



## jessehurlburt (Oct 18, 2017)

Hey newlawndude-

If I were you I would be investigating the conservation land with your town to find out if there are any special regulations regarding herbicides.

Crabgrass gets more difficult to control as it matures. What percent AI is the quinclorac you're using and are you using a NIS with it? You may need to get a higher concentration.

Are you planning to overseed this fall?


----------



## g-man (Jun 15, 2017)

Welcome to TLF. I'm moving this to the cool season forum.

If you apply the chemicals per the label to your property, you should be fine. Dont apply before a rain to avoid run off and maybe keep a buffer zone.

Corn meal is not a prem. Look at this report  from WSU.

Quinclorac needs MSO and it is best in young crabgrass. Dry ice has some handling dangers. It will also kill your good grass and a ton of work. You could carefully apply round up to the crabgrass leaves. I think that hand pulling the big stuff is the best option for 7500sqft.


----------



## g-man (Jun 15, 2017)

@newlawndude I forgot to mention you to be aware of the move.


----------



## ForsheeMS (May 21, 2018)

The crabgrass will die shortly after the first couple frosts. Yes, completely dead. The reason it comes back every year is all the seeds it has dropped during the summer will germinate in the following spring and throughout the summer. A good spring pre-m app of Prodiamine will help break that cycle. The crabgrass seed will still germinate but as the root gets into the pre-m barrier it will die. You will still have a few here and there that somehow manage to get through the pre-m barrier but in healthy KBG they should be really easy to spot and pull by hand before they are able to produce more seed.

Prodiamine is cheap! You can get a generic brand 5lbs container from domyown.com for about $65 and it will last you 10 years or more. For now I would do my best to just keep the crabgrass you already have from spreading any further. This means keeping it mowed before it goes to seed. If you have areas that are extremely heavy with crabgrass you could try pulling it out and reseeding those spots this fall and encourage the KBG to spread and fill in those areas. It will take a few years but eventually you should be able to get it under contro.


----------



## ken-n-nancy (Jul 25, 2017)

ForsheeMS said:


> The crabgrass will die shortly after the first couple frosts. Yes, completely dead. The reason it comes back every year is all the seeds it has dropped during the summer will germinate in the following spring and throughout the summer. A good spring pre-m app of Prodiamine will help break that cycle. The crabgrass seed will still germinate but as the root gets into the pre-m barrier it will die. You will still have a few here and there that somehow manage to get through the pre-m barrier but in healthy KBG they should be really easy to spot and pull by hand before they are able to produce more seed.


+1. If you can tolerate the crabgrass for the rest of this year, the real long-term solution is the next paragraph that ForsheeMS wrote (quote below.) You've already lost the 2018 battle against the crabgrass. The way that you are going to win the war (actually, the only way that you can, really) is to use a pre-emergent next spring to prevent the 2019 crabgrass invasion.

That said, properly-applied quinclorac should work well against crabgrass. Two necessary items, though, are use of a surfactant (as ForsheeMS mentions, MSO is the standard recommendation for quinclorac. I have used NIS with DriveXLR8 with good success.) and proper dosing. Read the label carefully, calibrate your sprayer, and make sure you're applying the right amount. Too little, and the crabgrass will survive. Too much, and you'll hurt your desirable grass, particularly if you have any fine fescue in the mix.

Quinclorac also has an Achilles heel with crabgrass -- it does great against new crabgrass (with <3 tillers) and mature crabgrass (say, 8+ tillers) but can be less effective on the adolescent plants. If most of your crabgrass is in that category, it may be able to shrug off the quinclorac and survive. The solution to that is to re-apply about 10-14 days after the first application.



ForsheeMS said:


> Prodiamine is cheap! You can get a generic brand 5lbs container from domyown.com for about $65 and it will last you 10 years or more. For now I would do my best to just keep the crabgrass you already have from spreading any further. This means keeping it mowed before it goes to seed. If you have areas that are extremely heavy with crabgrass you could try pulling it out and reseeding those spots this fall and encourage the KBG to spread and fill in those areas. It will take a few years but eventually you should be able to get it under control.


+1. The pre-emergent to prevent crabgrass is the real key to win the long-term war against crabgrass.


----------



## newlawndude (Jul 22, 2018)

Thank you all for the great insight and advise!!!
Yes, I used surfactant 1oz to the gallon (Baby shampoo) when I applied the Quinclorac which I bought at the Home Despot, can't recall the concentration. I guess I am not "throwing" it full dose and as @ForsheeMS said it might be the adolescent stage(I've seen 3-5 tillers).

Overseed, for sure, already got them seeds, waiting for Fall. But as things are looking I'm going to buy more.

I do have a 1 gal Chapin sprayer with the fan tip, I made sure the droplets were really fine on those leaves.
Things that I have realized I shoot myself on the foot are: Not been bagging, and mowing more frequently at 3.5 in, detached (never have done that before), frequent+short irrigation and "Throwing it Down" with Milo...

Ah well, I think I am still going to try the dry ice sheets for giggles, have access to the product and is not that expensive.

Thank you all for all the great advise and content in this forum, I may upload pics of the experiment.


----------



## Jconnelly6b (Mar 4, 2018)

When I bought my house and started taking care of the lawn it was overrun with crabgrass after the first summer. My wife and I pulled every single plant. We turned it into s competition who could fill the wagon faster.

If you have the energy and want to replace the crabgrass with desirable cultivars before winter, handpulling or roundup are likely your only option. Quinclorac May be too little too late at this point in the summer.


----------



## gene_stl (Oct 29, 2017)

I like the kind of thinking to use dry ice. But it probably is not a very good idea. This is from a person who went out with a weed burning torch yesterday afternoon and toasted whatever dallis broke through several and various treatments. ( I did move here 20 months ago. Second summer).

If you bought the quinclorac at a big box store it probably is on the low side of the dose curve. You should spot it at a higher dose. I sprayed it earlier in the season and it really toasted a lot of grassy weeds.

You have to make sure your timing is right if you are going to overseed. Pre emergent applied to seedlings can cause "root pruning" and probably cause damage. Get yourself some Tenacity. And some quinclorac granules. and and.....

If you can't resist the dry ice idea I would say make a dry ice and alcohol or acetone slurry. This will aid in heat transfer to the plants, and maybe even be easier and more precise to apply. Then after it warms up light it and let the plant get scorched. Both alcohol and acetone are very environmentally friendly.

I wouldn't worry about next door too much. Just make sure your sprays don't drift over there like with RoundUp. That works great on crabgrass by the way. If you have solid bunches of it probably the best idea.


----------



## JDgreen18 (Jun 14, 2018)

I'm a newbie here and trying to soak up as much knowledge as I can. Why no mention of tenacity? Doesnt it kill crabgrass? I used Scotts starter fert with Mesotrione on my 7 week old lawn that had a good amount of crabgrass, it has turned white and is starting to die.


----------



## b0nk3rs (Aug 21, 2017)

newlawndude said:


> Hi there, new guy here starting this never ending journey to have the best lawn on the street. But for now I have the best garden salad inon the street. I have the same battle most of you have with Crabgrass. *I would say the year season started with a 15% coverage of crabgrass* on my KBG. Since I started doing MIlo (in Apr and in July) with regular irrigation the crabgrass has taken off, I'm almost at 30% !!!. I started using Quinclorac (that' how is spelled?) and is barely doing an effect, it yellows and turns purple but it does not seems to die.
> 
> My major obstacle that I have to battle this thing is that My lawn sits next to conservation land, and I'm afraid using any chemicals might get me into trouble if big brother finds out. Specially Dimension.
> 
> ...


Please post some up close pictures because the above bolded line doesn't sound like crabgrass.


----------



## Green (Dec 24, 2017)

If it weren't for the conservation land...

----------------

Imho, in Boston, you still have another month and a half or more of potential crabgrass season. Plus, it's goung to start making seeds any day now...so if you can spray it, I would do so. Quinclorac works well on crabgrass that has gotten big, but it needs around 1/2 percent methylated seed oil by volume added in.

If you are experienced with herbicides, I would spray it. If not, and it's really bad, you can maybe get a pro to do it this time, if one is willing to do that type of job.

-------------------

No idea what the solution is on conservation land, sorry.


----------



## Green (Dec 24, 2017)

b0nk3rs said:


> newlawndude said:
> 
> 
> > Hi there, new guy here starting this never ending journey to have the best lawn on the street. But for now I have the best garden salad inon the street. I have the same battle most of you have with Crabgrass. *I would say the year season started with a 15% coverage of crabgrass* on my KBG. Since I started doing MIlo (in Apr and in July) with regular irrigation the crabgrass has taken off, I'm almost at 30% !!!. I started using Quinclorac (that' how is spelled?) and is barely doing an effect, it yellows and turns purple but it does not seems to die.
> ...


This is very possible. Or could be mix of a forage grass early in the season, and crabgrass now.

Since it's conservation land, you might have to live with it...definitely ask.


----------



## newlawndude (Jul 22, 2018)

@Green en I'll post pictures soon, I'm letting it grow on account to have more leaf surface area to do another quinclorac application. I am new at this (never dealt with herbicides) on top of the conservation land thing, so am going very carefully with until I talk to somebody in@green is king 01 
With respect to the dry ice idea, and learning as I go, is why wait for first frost, let the frost come to them. I am very familiar handling dry ice, transport etc..., I am not going to get to play with it for the next 2-3 weeks but definitely will give it a try, just for science.

Does anybody know how deep the seeds can go? 1", 3"? They obviously survive the winter, so I'm wondering if I can extend my experiment scope to see how much dry ice I can apply to "freeze down" the seeds. The do pre-emerge if I can.

Also will be posting pictures to be sure that is crabgrass. @Green Why do you think is not? Too quick? I have done Milo and had been watering very regularly this season, I think that why it has gone out of control.


----------



## newlawndude (Jul 22, 2018)

@Green I'll post pictures soon, I'm letting it grow on account to have more leaf surface area to do another quinclorac application. I am new at this (never dealt with herbicides) on top of the conservation land thing, so am going very carefully with until I talk to somebody in town.

With respect to the dry ice idea, and learning as I go, is why wait for first frost, let the frost come to them. I am very familiar handling dry ice, transport etc..., but I am not going to get to play with it for the next 2-3 weeks but definitely will give it a try, just for science, I think it will be interesting to see what happens.

Does anybody know how deep the seeds can go? 1", 3"? They obviously survive the winter, so I'm wondering if I can extend my experiment scope to see how much dry ice I can apply to "freeze down" the seeds. The do pre-emerge if I can. If by some miracle I can do pre-emerge I'll leave a specific area untreated to see the effect(if any).

Also will be posting pictures to be sure that is crabgrass. @Green Why do you think is not? Too quick? I have done Milo and had been watering very regularly this season, I think that why it has gone out of control.


----------



## jessehurlburt (Oct 18, 2017)

If you're planning on overseeding this fall, you could also paint the crabgrass with glyphosate and be done with it. You might kills some good grass around it, but you're seeding anyway. Maybe with something like this?
https://www.amazon.com/dp/B00116AAXO/?ref=exp_grassdaddyofficial_lv_dp_vv_d


----------



## Green (Dec 24, 2017)

newlawndude said:


> Also will be posting pictures to be sure that is crabgrass. @Green Why do you think is not? Too quick? I have done Milo and had been watering very regularly this season, I think that why it has gone out of control.


Because we don't get crabgrass germination temps until late May in the Northeast. The ground is too cold at that time. Whatever you mentioned you had in April and early May had to have been something else.


----------



## Green (Dec 24, 2017)

Just a guess, but I feel like the dry ice would "burn" it if applied to the leaves (ok, maybe that's not the right term), similar to heat or vinegar...rather than simulating a cold temperature with slow onset (like a cool night with frost). But I guess if someone is going to try it and see, it will be you, @newlawndude! Never know, you might find out something interesting. If you can actually cool the soil right near the plant...


----------



## gene_stl (Oct 29, 2017)

The CO2 would form carbonic acid in the soil and probably grab some calcium or magnesium immediately lowering the cation exchange capacity.


----------



## Green (Dec 24, 2017)

gene_stl said:


> The CO2 would form carbonic acid in the soil and probably grab some calcium or magnesium immediately lowering the cation exchange capacity.


Ok. That is definitely not a positive thing...

Unless maybe we are trying to chemically aerate, lol. (I'm trying to find a positive in it.)

Imagine if the government found out...


----------



## newlawndude (Jul 22, 2018)

Ok guys, is this some kind of wizardly potion? Just add some electrolytes to close the anion gap....

On a more serious note, tried to enjoy the mow this evening and this crabgrass has taken over, I will be losing the battle for the next five years or so. It's so dense, no joke the Milo does great things, all I have are patches of KBG, it's been raining all evenings this week and it has taken off, I even had clumps of crabgrass, I never had it that bad.

@Green here are some pics, I do remember noting the crabgrass during Memorial day, so yes, you were right. Like the great AvE once said; "My memory is excellent, just very short".

Found some documentation on the Town website and all they mention is that only use Organic herbicides on town properties, I guess that also include the Preservation Area, or that's State. Anyway could not get a hold of anyone with real knowledge about what are my options. I'll try again on Monday.

On the last pic, if you look close you'll see purple spots due to my application of Quiclorac 3 weeks ago, definetively way on the light side correct?


----------



## Green (Dec 24, 2017)

@newlawndude,

My three way herbicide with quinclorac seems to take a while to show damage to crabgrass...a week or so I think. It also seems to take at least two apps a couple of weeks apart to kill. I'm still feeling it out. I'm using MSO with it.

The reason to kill it rather than leave it, is so it doesn't take over your grass, you can overseed, and so it doesn't produce seed. Pure quinclorac has no impact on overseeding.

I've tried leaving it my first year doing lawn care, and it died in late Sept...but I had holes in the lawn from it that were too late to reseed. I think killing is the way to go.


----------



## Chaseweeks1 (Jul 27, 2018)

I spray MSMA on the yard every spring but I'm not sure if it will kill your KBG or not.


----------



## ken-n-nancy (Jul 25, 2017)

That's definitely enough crabgrass to warrant hitting it again with quinclorac. Be sure to check your dosing; is it possible that you may have underdosed last time?


----------



## newlawndude (Jul 22, 2018)

Want to give an update on what I've done.
On 7/27 I prepared 1 gallon of the quinclorac solution (Spectracide) with 3 Tbsp of J&J Baby Shampoo and spread it with a fan tip over a small 100 sq ft area. I went over 3 times making sure everything was soaked. Left for the weekend and when I came back on Monday night, all crabgrass had died, at least everything was brown with a paper like texture. My very few KBG spots were a good green, YAY!

Today I decided to re-seed the area, I could not wait!

This is what I did, let me know where I went wrong, if I did.

Mowed down to about 1.5 in. and bagged

detached again to make sure I have maximum soil exposure

Used a tool (don't know the name)similar to a grass stitcher to poke little holes

Seeded with Scotts KBG mix using the WIZ Spreader

watered thoroughly

I still need to put peat moss, will get it tomorrow.

I'll post some pictures in a bit.


----------



## newlawndude (Jul 22, 2018)

This is what I came to on Monday night.


After mowing, detaching and poking holes.



Overseeding.




Is this a correct seed density?


----------

