# Help identifying weed grasses and making a plan



## Nathan T (May 1, 2018)

Hi TLF! I've found helpful threads on here a few times, but first time posting.

Three years ago we landscaped our whole back yard. Since the lawn was in very rough shape from previous owners and we were making significant changes to add patio and such, we decided to just re-grade the whole area, bring in new soil, and re-seed. It seemed to establish itself alright in the first spring and thicken over the summer. The next year was good aside from a lot of weeds that I stayed on top of with hand picking, and a strip along the back that gets a lot of shade and moisture. Last spring though, when the lawn woke up from the winter, unattractive tufts of lighter grasses sprung up all over the place. I dug all these out, replaced the soil and re-seeded, and the re-seeded sections seemed to do well; by the summer they had blended in with the rest of the grass and looked good.

This season though, it's the same problem, only worse. Here's what I'm seeing:









It looks like maybe there are a couple different types-one with reddish leaf sheaths and one without. Both are much lighter green than the rest of the lawn, and grow three times as fast. After doing some research I decided to try spraying the patches with Tenacity, since it would be a lot to dig out by hand. Did that almost a week ago, but haven't really noticed any effect, so I'm guessing these aren't among the varieties it controls.

So, I'm at a loss. I can't dig half the lawn up every year, but it looks pretty bad as-is. Much of the lawn is shaded by a large hedge, but this undesirable grass is invading the sunnier areas just as much. I think part of the problem is drainage; although we tried to slope the (mostly clay) dirt layer when landscaping, and added a fair amount of sand/soil mix on top of it, most of the lawn still tends to be pretty damp through much of the year. Going to try to address this by adding some drainage through the worst section, aerating, and adding sand. (Aerated in the fall as well, and regularly over the past years, but I feel like the damp soil quickly closes back in; hopefully the sand will help with that.) But I have no idea whether that will work.

So... can anyone identify the grasses I have here, and confirm whether they're taking over the lawn due to drainage? If so, am I on the right track to try and deal with that?

Then as far as getting rid of what's already growing; am I right to assume I would have seen whitening within a week if the Tenacity was going to work? It's lighter than the rest of the lawn, but always was. I don't think the color has changed. Given that, is there anything I can do to get rid of it short of digging it all out again? Roundup is prohibited in my municipality fwiw.

And finally, if I do dig it all out again (or pay someone to do it as I think it'd cost me several days and my sanity to do it myself...), I'm considering patching with sod this time rather than seeding, to get the holes filled back in faster and thicker. Good/bad idea? Regardless I'll probably want to over-seed as well since the whole lawn thinned out a fair amount over the winter. Will also be raking out the moss and applying lime.

Thanks in advance for any input!


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## g-man (Jun 15, 2017)

Welcome.

Give tenacity 2-3 weeks to show any effect.

What is the source of you seeds? And your soil? I can't I'd it. Could you dig one out to see it better?


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## ericgautier (Apr 22, 2017)

That looks like something @critterdude311 posted earlier. See this post.


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## Nathan T (May 1, 2018)

ericgautier said:


> That looks like something critterdude311 posted earlier. See this post.


Yes, it does look very similar to the variety I have with the purple sheaths. So, hopefully Tenacity will take care of it as it did for him. If that's the case, I should be able to use Tenacity as a pre-emergent next year to avoid this situation again.

So, if the Tenacity does work, do I just leave the bleached section alone until they decompose? Or does it make sense to pull it out at some point?

Unfortunately I don't know the source of the soil or seeds as the landscaper that did the yard disappeared soon afterward. Any over-seeding or patching we've done since has been with Natural Knit perennial ryegrass.

Will pull out a bit of each variety and take pictures later today...


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## Nathan T (May 1, 2018)

So, I think the sources of the invading grasses are our neighbours on either side. This red sheathed stuff is coming from the neighbour on the right, and I _think_ it might be starting to react to the Tenacity. I saw some slight lightening, and I pulled out a few of the smaller clumps and found they came out easier than I'm used to. Thinking this is barnyard grass or similar. Here's some growing in the gravel where it's easier to see:



Then from the house on the other side we have a smaller area of lawn being invaded, but much more thickly:



Their whole lawn is this grass. Closeups:





This stuff unfortunately doesn't seem to be having much of a reaction to the Tenacity, at least not yet. It's similar to Poa Annua (which we've had small clumps of and I've just kept on top of by hand) but not identical. Is this Poa Trivialis? Anyway, it doesn't cover too large an area, so if necessary I could dig it out. The question would then be how to stop it coming back from right across the fence. I could add a barrier in the gap under the fence (down to say 6-12" underground) to try to stop it coming through there. Some seeds would presumably still blow over top, since this stuff goes to seed extremely short. (The neighbour mows to about 2", maybe shorter, but I can still see numerous seed pods in their lawn.) But maybe it wouldn't be as bad. Maybe there's a pre-emergent that would control it as well?


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## Nathan T (May 1, 2018)

OK, the Tenacity seems to be working on both sides. Growth of these patches slowed down a lot, and they've whitened significantly. A few of the patches in sunnier areas appear to be dying. I just finished re-spraying.

So, next question. Once these patches die off completely, do I rake them out? Or do I have to just leave them there until they decompose? One thing I was thinking is I could mow extra short one time, then let the surrounding grass grow back longer to disguise those areas..


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## GlennBlake (Feb 28, 2018)

@Nathan T where did you purchase Tenacity on the Island? I have a problem weed that Later's and KillX are not touching! Need to try something with a bit of umph.


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## Nathan T (May 1, 2018)

GlennBlake said:


> @Nathan T where did you purchase Tenacity on the Island? I have a problem weed that Later's and KillX are not touching! Need to try something with a bit of umph.


I had to buy it from a US supplier (domyown.com) through a shipping forwarder. The only Canadian source I found online seemed super sketchy (no SSL on the payment page and various other red flags), and was more expensive anyway. Ordered some surfactant and blue dye from the same source so I wouldn't have to try and find them elsewhere.


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## SNOWBOB11 (Aug 31, 2017)

@GlennBlake @Nathan T I'm in Ontario and I order my herbicides including tenacity from seed ranch or seedworldusa.com. There the same company. They ship north of the border fairly often it seems and I've never had problems with items getting stoped at the border.


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## GlennBlake (Feb 28, 2018)

Thank you @SNOWBOB11 I did see seed ranch.ca on the Interweb last night. I will perhaps give them a go after checking out domyown.com. Thank you @Nathan T


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## Nathan T (May 1, 2018)

@GlennBlake @SNOWBOB11 I think seedranch was the one I ended up not ordering with because their credit card page was served over http. Basically leaves your credit card info open to snooping (and definitely isn't PCI compliant). I'm actually surprised to hear they're a legit company! Figured it might be some left-over defunct website. Maybe I'll send them a message to let them know about it.


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## GlennBlake (Feb 28, 2018)

@Nathan T which shipping forwarder did you use? domyown seems the best choice at the moment.


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## Nathan T (May 1, 2018)

@GlennBlake I usually use Express Air. You ship to Washington state, then they truck it from there up to their warehouse at the Victoria airport. Then you go pick it up, and just have to walk over to the terminal building with the customs slip to self-clear. Added bonus is that you save the brokerage fees that the shipping companies charge. Extra added bonus is that they sometimes don't bother to charge taxes for purchases under $100-$200 or so. Costs around $15 for most packages; more for heavy ones. (But not too bad. I received an entire set of 19" wheels and tires once and I think it cost about 80 bucks.)


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