Disappearing lawn

[Mathew Newton]

I would be grateful for input from any gardeners out there...

In June 2014 I removed the patio and subbase from our back garden and repla ced it with Rolawn's Medallion turf sat on approx 6-8 inches of their Blend ed Loam topsoil. Underneath this was the original heavy clay subsoil. Here' s how things looked in once laid:

A year later it was still going strong:

However, the past few months have been a different story and we now have th is shocking sight:

Does anyone have any idea what has happened?

As you can hopefully make out, there do not appear to be any weeds or moss but rather the grass has seemingly disappeared. Note also that some areas ( in the last photo) are still relatively lush in appearance.

We have always had some issues with earth worms and last year I was sweepin g away casts regularly. Could this be it?

I am assuming that I will ultimately end up reseeding, or at least overseed ing, however I am keen to ensure that I understand what has happened and ho w to prevent it reoccurring.

Any thoughts and/or suggestions?

Mathew

[spuorgelgoog]

You haven't had any incontinent apprentices in recently?

Owain

[Malcolm Race]

As you have sid that it is on a heavy clay sub soil my guess would be a drainage problem - which area of the country are you in?

I would suggest you post to uk.rec.gardiening along with your location. There are some experts on that group, although not many regular posters.

Malcolm

[Mathew Newton]

We're in Wiltshire.

I did wonder about drainage and thought I'd mention the clay subsoil becaus e of it. However, from what I can tell the garden seems to drain okay - eve n the heaviest and most persistent of rain drops recently have not resulted in any obvious signs of poor drainage i.e. no puddles during/afterwards (p erhaps that is not a useful indicator though).

Will do, thanks for the suggestion.

[Tim Watts]

There has been a very large amount of prolonged rain this year - my feeling is that it's shown up a drainage problem.

Some might recover when we get to spring - I have patches that get waterlogged and do that, then recover.

[The Natural Philosopher]

That is one, another is that pets or people are walking on the areas that are bare and simply wearing it out. That's what the school rugby pitch used to look like in January, too.

But even waterlogged clay should support some sport of grass, it may be that you need a particular water loving sort of grass.

[The Natural Philosopher]

yep fork it to pierce h clay pan and enhance drainage, and then try a bit of fertiliser come March or so.

[harry]

laced it with Rolawn's Medallion turf sat on approx 6-8 inches of their Ble nded Loam topsoil. Underneath this was the original heavy clay subsoil. Her e's how things looked in once laid:

this shocking sight:

s but rather the grass has seemingly disappeared. Note also that some areas (in the last photo) are still relatively lush in appearance.

ing away casts regularly. Could this be it?

eding, however I am keen to ensure that I understand what has happened and how to prevent it reoccurring.

Waterlogged I would say. You may have made yourself an underground pond. Dig a hole in the worst af fected area and leave for a few hours & see if it fills with water. Or you needed sand mixed with the soil you laid your turf on.

[stuart noble]

+1 I think I might lift the turf in the waterlogged areas (as it's relatively new) and mix about a third sharp sand with the loam. It would also help to get a fork well into the underlying clay at intervals.

[Mathew Newton]

Noting that the underlying clay is ~8 inches down any suggestion how best t o go about forking it to improve the drainage?

Incidentally, whilst the consensus seems to be a drainage issue and that pe rhaps it is this winter's extra rainfall that have cause any issue when las t year's was okay, there is something else that might be worth mentioning.. .

Last year I noticed that whenever I removed the odd weed that appeared in-b etween mowings I often found a 10-15mm long grub at the root of it. I thoug ht nothing of this fact at the time however I have just been reading about leatherjackets and what damage they can do to a lawn. I can't help but wond er if that's what these grubs were and indeed if this is what has led to th e grass loss?

[Mathew Newton]

Will give that a go this weekend if time/weather allows.

Oh great... ;-)

Rolawn's blended loam does contain sand - I take it you mean I needed more?

[Chris Hogg]

I'd go with what several others have said - drainage (it has been a very wet few months), possibly coupled with being walked or played on while soggy. The fact that you've got lots of worm casts would support that idea - the worms are in danger of drowning and are coming to the surface to breathe.

As to what to do about it, I'd spike it all over with a garden fork, driving it down as far as you can, preferable full depth, and giving it a wiggle, and then move on 12 inches and repeat. Do it over the whole lawn. Hard work, but it's not a huge area. Soon after, before the holes have time to close up, apply sharp sand in generous amounts and brush in with a stiff broom. Aim to get sand down the holes. More hard work.

Don't be tempted to get one of those hollow-tine lawn spiking devices, spring-loaded or otherwise. They're utterly hopeless! You spend a whole lot more time clearing the hollow tines than actually doing the spiking, and they don't go that deep anyway. Use a fork!

Given all that, and a bit of dry weather, it should recover.

[Tim+]

Quite possibly but I don't know if they can cause this much damage. I think that there are products that can kill the blighters.

Tim

[Tim+]

Incidentally, we've found paying a professional lawn treatment firm is more cost-effective than buying fertiliser/moss killer etc ourselves. Sure they'll be happy to give a quote and could save you a *lot* of work if it is just a bad case of leatherjacket infestation.

Tim

[tabbypurr]

laced it with Rolawn's Medallion turf sat on approx 6-8 inches of their Ble nded Loam topsoil. Underneath this was the original heavy clay subsoil. Her e's how things looked in once laid:

this shocking sight:

s but rather the grass has seemingly disappeared. Note also that some areas (in the last photo) are still relatively lush in appearance.

ing away casts regularly. Could this be it?

eding, however I am keen to ensure that I understand what has happened and how to prevent it reoccurring.

Only a few observations. As said, saturated ground, the wrong type of grass & overuse (which only means normal use for some grass types) are all candi dates.

I'm also wondering about the worm casts: a lawn needs worms to provide fert ility, or the grass doesn't grow. The only issue would be if you didn't get them.

Also reseeding isn't usually the solution. You have grass, it's more a ques tion of sorting out the growing conditions so it flourishes & spreads. Howe ver you might just have the wrong grass blend. If that's possible I'd look at adding a low level of a blend designed for heavy use & bad drainage. Don 't remove the existing grass, obviously.

I'd wait until the spring and add the right seed & fertilise. A little home breweed compost, not much, may also help.

NT

[Mathew Newton]

ss & > overuse (which only means normal use for some grass types) are all

I can definitely rule out overuse. There is only the wife and I and, as you can see from the photos, the layout lends itself to only a couple of thoro ughfares and yet the problem is all over. There are two cats also however t hey stick - rigidly to discrete foot holes - to specific paths also.

Yes; I have assumed that the earthworms are only eating rotting matter and not the roots and so shouldn't be causing damage beyond the production and consequences of casts.

I've just been out and had a quick dig - having removed barely a mugful of soil I found 2-3 grubs which, if indicative of density across the lawn, mea ns there are thousands and they must be feeding on something. I will line s ome up for a photo and identification tomorrow. I have also laid some layer s of weed-stop fabric down and given it a good watering to encourage more t o take part...

Mathew

[tabbypurr]

f soil I found 2-3 grubs which, if indicative of density across the lawn, m eans there are thousands and they must be feeding on something. I will line some up for a photo and identification tomorrow. I have also laid some lay ers of weed-stop fabric down and given it a good watering to encourage more to take part...

I can't imagine how weed stop fabric could help. And watering, seriously?

NT

[Tim Watts]

I have clay 2-3' down (and near the surface in other places).

My clay is to all intents and purposes infinitely deep - at 3' it needs an iron bar to loosen it - it is like shale.

I plan, because I have a slope, to dig 2' deep trenches in a grid and fill those with 20mm to some depth, then cover over, plough and mix a lot of sand into the top layer - with the aim of sending most of the water to the lower part of my garden.

[stvlcnc43]

From your pics I think that the grass is buried under the amazing number of worm casts. The warm and very wet season has caused the worms to move high er above the clay level; they are fighting to aerate the too-wet soil. The problem is worse where the lawn gets the run-off from the paving.

[Mathew Newton]

It apparently brings grubs such as leatherjackets up to the surface, presumably by blocking out the dawn light which would otherwise cause a retreat.