[Lawnmower_Man]

Hello,

I just laid out Kentucky Bluegrass sometime in November, and I am kind of surprised to see that (after barely its first season) my grass is already pretty yellowish, and I have this strange set of weeds forming so quickly into the new season.

I'm in Toronto, and the Forsythia bloom has literally just begun today (there are some bushes in my neighbor's yard that were pretty bare yesterday, and have bloomed yellow today) so these weeds in my lawn just sprung up out of nowhere.

I'm planning on applying a big bag of CGM, to act as a mild fertilizer and pseudo-PreEM (since I already have the bag, I might as well use it). I was maybe thinking about calling a lawn guy to apply something, but I don't want just some random pre-Em if it won't work on this type of stubborn looking weed (looks like barngrass, crabgrass, or one of those other types that have a firm and purple-ish stem).

1. Does anyone know what kind of weeds these are? And if a Pre-Em would even work at this point? (or should I just yank them out manually)

2. Would applying some compost or another type of fertilizer assist in turning these yellow patches green (my neighbor's lawns look greener, even though mine is newer).

Any assistance is much appreciated!!!

 

[Lawnmower_Man]

Friends, Amigos. Please. I'm a broken man here.

 

[SNOWBOB11]

Couple things. Pre e has no effect on weeds that have already sprouted. Pre e stops the germination of weeds in the first place (or actually lets them germinate and kills them before they take root). So no pre e will take care of the weeds that have sprouted in the lawn currently. Furthermore corn gluten is not a real pre e. It's an ok source of organic matter but really has little to no effect as a pre e despite what the bag of scotts weed preventer says. My guess is these weeds were probably there in the soil before you put the sod down. One question, why did you wait so late to sod last year?

 

[g-man]

It looks like either quack grass or orchid grass. In the last image, could you take a closer picture of the auricle? It is located near your ring finger.

 

[Colonel K0rn]

If it's any consolation, the DOT didn't put down any PreM on the sod that they laid down at the new rest area that they rebuilt last year, and you could clearly see the lines of the sod riddled with nutsedge. You'll get yours under control soon.

 

[Lawnmower_Man]

It looks like either quack grass or orchid grass. In the last image, could you take a closer picture of the auricle? It is located near your ring finger.

Sure. Here's a closer shot.

 

[Lawnmower_Man]

Couple things. Pre e has no effect on weeds that have already sprouted. Pre e stops the germination of weeds in the first place (or actually lets them germinate and kills them before they take root). So no pre e will take care of the weeds that have sprouted in the lawn currently. Furthermore corn gluten is not a real pre e. It's an ok source of organic matter but really has little to no effect as a pre e despite what the bag of scotts weed preventer says. My guess is these weeds were probably there in the soil before you put the sod down. One question, why did you wait so late to sod last year?

Thanks.

Yes, I plan on manually pulling these out. Yea, I had a bag of leftover CGM, so I spread it out anyway to use it up. Worst case, it helps get the lawn a bit greener as a fertilizer.
It's pouring rain now, so the good news is it will break down and enter the soil (instead of having the birds and rodents feast on it)

To answer your other question, we waited late last year because it was a new home with a newly graded lawn and it was unusually warm late last year so we figured we may as well just sod it.

I will look into Pre-Ems but I want to know what type of weed this is (to better select an appropriate Pre-Em).
If anyone can figure out what weed this is above, it would be a great help!

Also, does anyone recommend I top-dress my lawn with soil or apply some fertilizer to green things up a bit more?

I always fear top-dressing (as I don't know what weeds seeds lie in there). Maybe a natural fertilizer or compost makes sense?

 

[g-man]

I'm not sure. The top portion doesn't seem to have the auricles, but the bottom looks like it.

Look at this link and compare the images. http://purdueturftips.blogspot.com/2015/06/weed-of-month-for-june-2015-is.html?m=1

 

[probasestealer]

This specific weed might change your postemergent herbicide, but not the pre-emergent choice.
Dimension is approved in Canada, I don't know about barricade or Halts.

 

[g-man]

I was able to zoom in more in the home PC, than the cell.

It is quackgrass. There is no prem against it. It also spread by pulling it via the root system. The most effective way to get rid of it is with Round up (glyphosate). With a lot of care, paint the leafs without touching your sod.

Can you get round up in Canada?

 

[SNOWBOB11]

This specific weed might change your postemergent herbicide, but not the pre-emergent choice.
Dimension is approved in Canada, I don't know about barricade or Halts.

Dimension isn't approved in Canada that I know of. I get my pre e from the US and get it shipped here. I don't think there are any pre emergents that are allowed here.

Yes @g-man you can get round up here. They sell the pre mixed ones but you can't get the concrete type. I think the pre mixed type has a lower % of glyphosate though.

@Lawnmower_Man I'd do what g-man says and carfully paint the grassy weeds with a paint brush and round up.

 

[Green]

Corn plants from cgm? Corn is a grass, too. It's a little far fetched though as there shouldn't be corn in it. And I don't think that's what it is anyway as it doesn't look right. Question is how did a grassy weed get past sod?

 

[probasestealer]

@SNOWBOB11

The only reason I knew about dithopyr (Dimension) in Canada is because I reviewed the safety data. I've got 2 young kids and try to be careful about everything I apply.

I cannot find the article I read, but here is the 2009 article.
http://publications.gc.ca/collections/collection_2009/arla-pmra/H113-28-2009-15E.pdf

 

[SNOWBOB11]

@probasestealer Interesting, I've never seen any stores that carry or products that have dithopyr. But according to the article it does seem that it is an approved product.

I just read back my first reply to you and it seemed a bit curt, but I never meant it that way. I think it was late and I never re read what I wrote and it didn't come out like what I meant it to. Sorry if it seemed like I was being harsh or anything.

 

[probasestealer]

@probasestealer Interesting, I've never seen any stores that carry or products that have dithopyr. But according to the article it does seem that it is an approved product.

I just read back my first reply to you and it seemed a bit curt, but I never meant it that way. I think it was late and I never re read what I wrote and it didn't come out like what I meant it to. Sorry if it seemed like I was being harsh or anything.

No worries, I didn't take it that way.

Article is from 2009, it's possible things have changed. I often times look at what Canada deems "safe", you all are more conservative with chemicals, which I'm a fan of overall.

 

[Lawnmower_Man]

This specific weed might change your postemergent herbicide, but not the pre-emergent choice.
Dimension is approved in Canada, I don't know about barricade or Halts.

Dimension isn't approved in Canada that I know of. I get my pre e from the US and get it shipped here. I don't think there are any pre emergents that are allowed here.

Yes @g-man you can get round up here. They sell the pre mixed ones but you can't get the concrete type. I think the pre mixed type has a lower % of glyphosate though.

@Lawnmower_Man I'd do what g-man says and carfully paint the grassy weeds with a paint brush and round up.

so there is no way to remove quackgrass manually?

I'd like to avoid Roundup if I could, as I plan to put a garden nearby.

 

[ryeguy]

Not effectively, since quackgrass spreads via rhizomes.

You said you plan to put a garden nearby..as in, it isn't there yet, right? If that's the case, glyphosate should be safe to use as it has no residual effect in the soil. It's even perfectly safe to spray it and put grass seed down at the same time with no ill effects.

If there's something nearby that you're worried about damaging, you could always fill a small cup with a glyphosate solution, grab a paintbrush, and slowly apply it that way. Tedious, but precise.

 

[alpine0000]

I'd like to avoid Roundup if I could, as I plan to put a garden nearby.

RoundUp won't affect your future plans for a garden, unless you are planning to put a garden in that exact spot tomorrow or something. It doesn't really stay in the soil like that. It's a foliar application that the weeds/grass take into the roots. After you get a bunch of rain, the RoundUp is gone and ineffective. It generally breaks down in the soil within a week or two regardless. But this is even less of a concern if you are just painting it on the leaves of the grassy weeds and not doing a mass spray. And especially no concern if your garden isn't even in the spot where you are painting the glyphosate on the leaves of the weeds.

 

[Lawnmower_Man]

I'd like to avoid Roundup if I could, as I plan to put a garden nearby.

RoundUp won't affect your future plans for a garden, unless you are planning to put a garden in that exact spot tomorrow or something. It doesn't really stay in the soil like that. It's a foliar application that the weeds/grass take into the roots. After you get a bunch of rain, the RoundUp is gone and ineffective. It generally breaks down in the soil within a week or two regardless. But this is even less of a concern if you are just painting it on the leaves of the grassy weeds and not doing a mass spray. And especially no concern if your garden isn't even in the spot where you are painting the glyphosate on the leaves of the weeds.

Good to know.

So, essentially, by painting the quackgrass leaves carefully with Roundup (so I don't get any onto the surrounding grass) it will poison the roots via systemic absorption through the leaves to the horizontal roots underground.

How long does it take to take effect?
Is Roundup effective? or is it just the best of the worst?

We may be without rain for a few days (starting tomorrow) so I will buy some and apply it over the weekend.

On another note...
I will have some extra sod later in the summer (as I plan on expanding my paving stones in my backyard).

It may make sense to dig out all the quackgrass and the surrounding area altogether.
Remove the quackgrass, its roots, an inch or two of soil and replace it...and move that clean weed-free grass (that I have in my future paving stone area) in its place.

Does replacing that area of grass make more sense?

Not sure if THIS is a better option than the Roundup, but that will involve me waiting until later in the summer (which may be a bad idea if the quackgrass spreads).

 

[SNOWBOB11]

If it was me I wouldn't dig out the sod and replace. I'd just go the round up route. Round up is very effective. It will kill all grass it touches basically so be carful with it.