Annual Meadow Grass How to Control and Prevent

Meadow Grass Control and Prevention Options and Preventatives

This blog explores a few possible options in removing and managing (poa annua) meadow grass, found on so many of our sports pitches. We look at solutions and control methods, whether that is from a professional groundsman’s or grassroots groundsman’s point of view.

It is rife this year, through a combination of a very wet winter, as the seed from the previous summer begins to germinate in late October, followed by a very hot and dry April. Both of these conditions are ideal for poa and they begin to become more and more apparent from the start of April onwards.

Even the best looking swards of grass can be susceptible to being invaded by this weed grass and controlling it, preventing it and eradicating it can sometimes be a bit of a fine art whilst causing many a headache in the process.

Poa Annua is derived from the ryegrass family and is a common weed of this common grass type. This doesn’t mean it will only appear in ryegrass though, like most weeds, it’s really about getting ahead and then continuing to follow processes.

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Verti-Cutting Annual Meadow Grass

Done properly I personally feel this is the quickest most effective way of removing the seed and the stalks from within your sward. Verti-cutting allows for deep penetration to the base of the grass leaf and removes various unwanted weeds, weaker grasses and invasive species leaving you with a clean profile.

Doing this option thoroughly is key to its success, a simple up and down walk along the usual direction of cut with say a Thatch-away isn’t going to take much of our poa out of the sward.

What I suggest is to cut in a diagonal across the usual cutting directions as pictured below this paragraph. Usually 2-3 passes will have removed 95% of the problematic weed growth using a Thatch-away or similar verticutter.

The reason I mention a Thatch-away pedestrian machine is simply because they have to be one of the most underrated machines on the market, in my opinion. Only the groundsmen that are lucky enough to have one truly appreciates its value to creating a healthy growth within their turf profile. They are less invasive than a scarifier and aren’t designed to enter the soil profile as a scarifying mower or tractor attachment would be.

I would beg, borrow or steal (Don’t actually steal one!) to get a Thatch-Away to the club I work at. They are prolific at removing our poa stalks and seed.

Follow the 2-3 passes with the verti-cutter with a reel mower boxed off at the usual height of cut to sweep up any remaining seed. The results are almost instant as you can see from some of the photos attached below.

If after this quite heavy process of verticutting, if the sward looks thin this maybe the perfect time for an over seed if you have the means to do so.

Note -I have found if possible after standing the poa seed up, using a rotary or and a power brush is more effective at collecting seed heads over cutting with a cylinder mower.

Alex

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Clubs Without a Verticutting Machine or Cassette Unit(cricket/football)

It is very easy for us guys with the machinery to advise this and that, but l am also aware of those guys who have very limited machinery, so l have just listed a few more grassroots ways of trying to make some progress with the problem.

1-The use of a sisis lawman, these can be picked up for around £600 and a must buy, whatever level you’re at. It is two sided, one being brush the other being a rake. (cricket)

2-More cultural methods of standing up the poa, with the use of a spring rake, drag mat or weighted brush will all help. Maybe just do two different wickets a week over the spring /early summer period. (cricket)

3-Use of a multi tool tractor attachment, which is a combination of attachments in one unit i.e., rake, roller and brush (football)

4-Speak to your country cricket board, many have their own scarifier for end of season renovations and rent these out at very reasonable rates.

5-Grants are often avaible at the start of the new year through your county cricket board or as part of the pitch improvement programme with your local fa.

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Other Annual Meadow Grass Control Options?

1-Starving it out as poa is shallow rooted, is an option l hear and maybe worth looking into but l  have my concerns unless really thorough renovations and seeding is done, you could end up with additional problems and maybe more poa.

1-I hear of groundsman total weedkilling and removing all vegetation from their squares, at the end of season. l am not personally sold on this as my concern would be left over vegetation and organic matter left over, something more for me to look into maybe.

3-Currently there are no chemicals on the market to control/kill poa for turf areas.

4-Primo Maxx is a growth regular and will stop poa from seeding, on existing plants so a process of removal will still be needed. Primo to be applied by a certificated spraying operator l believe.

5-High phosphorus levels are said to contribute towards high levels of poa. Annual soil nutrient testing is the only way of monitoring and managing this, testing usually takes place when the plant is more dormant i.e Jan/Feb.

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Scarifying of Poa- End of Season (cricket/football)

You can also use a good scarifier to a semi kind of effect, meaning it won’t completely remove the top profile but done enough times in enough directions it will remove the vast majority of the weed grasses and thatch.

Poa annual in particular doesn’t grow so well within thick, well fed sward. The healthier and thicker the sward the more chance you have of avoiding a poa problem!

Poa and thatch like nothing better than a light scarification, but for scarification to be affective it needs to be aggressive in nature.

You should NOT be worried it looks battered and maybe only 20/30% of the surface is left grassed after.

The left over scarifying lines are the perfect seed bed for you to put the seed (rye) in at ,70 gram square metre.

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Fraise/Koro Mow the Surface-End of Season

If your poa problem has taken over then the chances are your grass sward was quite weak initially, making it susceptible to the poa weed grass and other weeds taking a hold.

Koro’ing a surface is quite expensive and some would see as an extreme measure to remove annual meadow grass, ultimately without it you will never really regain control of a healthy grass growth whilst weeds find it so easy to germinate within the sward.

This problem will continue if the sward is already saturated with poa and other weeds, meaning the most effective way for you to eradicate the problem is to koro the surface and start a fresh.

If you do go down this route, it will need considering once every three years or so, by a specialist contractor. This will remove the shallow rooted weed grass, and if you’re lucky the process will leave the ryegrass to regrow back, but you shall also need to over seed.

Alex

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Conclusion

Most option are not a magic wand thought, unless you can afford to fraise/koro off yearly or have the very best resources available.

Another consideration to think about, if your outfield or surrounds have a lot of poa in them, the fact is it is quite likely to find its way back.

Long term whatever options you are taking bio weekly verticutting (spring) and aggressive end of season renovation, should be the norm.

Some things worth bearing in mind and something l am keen to look into is the link between a lack of soil microbes (soil life) and poa.

Soil drainage is also said to play a negative role in formation in annual meadow grass build up (a challenge on heavy soils/loam), as with over feeding and over watering, so more room to look into that for a later blog.

So, don’t be so hard on yourself, most of us even at the top grounds are fighting the dreaded poa.

Alex Fitzgerald and Brian (Preston Nomads CC)

Ps-If you have any techniques or suggestions please do feel free to reply in the comments box below.

We are at differing stages of learning so any feedback or suggestions welcomed.

For a bit more reading on poa in terms of how the greenkeepers are dealing with it, take a look at this blog below.

https://turfcareblog.com/poa-flower-in-putting-surfaces/