What can I do with all this (cooch) grass

Hi all

I read back a few pages and did some searches but did not see anyone talking about keeping lawns under control, mostly people seem to have problems growing them. Ours is mostly the opposite.

We have a type of runner grass called "Cooch" - Planted by the previous owners, most likely because if the property HAD any top soil, it was probably scalped and sold by the builders when they put up the house. Essentially we have 6 feet of hydrophobic clay on approximately 1 acre.

This type of grass forms runners 20-30cm (8-12 inches) underground and can travel LONG distances from the nearest leaf, popping up anywhere. The grass can grow to a height of 60cm (2 feet) or more and out competes anything. We do not water or do *anything* to the lawn other than cut.

The issue is it is incredibly invasive, and if you do not weed an area constantly, within 1 month (in summer) that area would be essentially only grass with all other plants lost.

Question: Does anyone have any proven techniques to control an invasive runner grass? (I'll post what we tried and why they failed for us below)

What we are trying now:
1) 50cm (20inch) deep trenches around all areas we want to exclude the grass, vegetable beds and the like
2) Freeing existing areas of grass by placing down cardboard, then lots of mulch. Works to a point, and grass that grows up is easily removed, but it still requires constant weeding. (I'm not really worried about the cardboard not breaking down as noted on these forums, there isn't anything under it except concrete hard clay and cooch grass anyway)
3) (future) Ducks, most likely Muscovy ducks to eat and keep the grass/lawn areas manageable over summer with reduced mowing. Planning on checking the Fowl section here later, since I am seeing contradictory stories on Muscovys (They love to eat snails and slugs, they don't touch snails and slugs....! I'd have thought it would be one or the other, both can't be true)

What we tried (and failed or was discounted immediately)
1) Poisoning all the grass. Not an option, this would destroy the garden as it stands and put us back years. The poison used for cooch must be applied with am wearing a fully body suit and respirator as far as I know.
2) Geese. Worked initially, but a small flock of 3 were unable to make any sort of dent in the grass during summer (Winter they did ok) - I butchered all three after it became obvious they were too aggressive for our small area, almost killing the chickens on several occasions and attacking everyone other than me
3) Weed matting. (and a carpet, still digging up the bloody thing) The grass just traveled under ground (for many meters/feet) and found a hole, or made one, and grew up through it
4) Wooden edging. Unless the edging is 50cm (30inch) deep the grass can still burrow under it. Does make it easier to trim the edges though
5) Planted borders. No plant we tried could out compete the cooch. We have a Pigface (cactus) bush, about 1m (3 feet) across with grass growing out the middle of it. I've seen it grow up from under a 2 or 3m (6 - 9 feet) dense bush and growing up out of the top.

Preferably I'd like to be able to USE it for something. It makes great compost when we mow it with a catcher, it breaks down quickly. Though woe betide us if we get some roots in with the compost, no matter how deep it is in the center nor how hot the heap gets it still seems to survive and grow!

Check out the threads on 'couch grass' or 'quack grass' - same thing. I've battled it myself. My strategy now is to first manually weed the planting area very thoroughly and then keep the perimeter weeded.
I think comfrey and rhubarb might work as a perimeter.

Thanks for the reply!

With the different spelling (and quack grass which I'd never heard of) a lot of results came back in search!

Seems like we are on the right track then, manually weeding and keeping a trench perimeter.

I'll investigate comfrey (something we want anyway) and look at where our rhubarb is planted (something we have a lot of a love using)

If you are looking for elimination and not just control and there is nothing valuable in the area try pigs. Fence them in the area for a few months. They will root out all the roots till there is nothing left. And if they should somehow leave something behind they will kill the shoots up off till the root dies. In tougher soils water so the dirt is soft enough for them to root. It is the one non-chemical means of cleaning up bind weed and morning glory patches that I know of and should work against any other plants that pigs can tear up. Be aware that after this treatment you will have to rebuild soil organics. One solution after the plants are rooted out is to spread bedding on the soil and water and let the pigs tramp it in. Remember you still have seeds to deal with but usually they can be choked out with other planting materials in strong plantings once the roots are destroyed.

A testament to the power of pigs to change ecology. Growing up we had a corner of a field with a cat tail bog in it and in spite of maintaining drainage it reformed every year even when plowed out. One year in the late 70's we fenced it and put about 100 feeder pigs on it. Within 2 weeks the 6 foot tall cattails were nearly all gone with just a few stalks sticking up out of a huge mud hole.(understand this was 5 to 10 acres worth) Withing a month the mud hole was dry with the water running through the ditch like it was supposed to. It took nearly 20 years for that cattail patch to reestablish in that site.

Essentially I'd *like* to eliminate but it just isn't feasible, even with pigs since it it is so scattered around the garden we would be eliminating all other plants too

We actually did have 2 pigs limited to certain parts of the garden via electric tap with the explicit goal of killing the grass in those areas. They were Large Black cross Tamworths, no nose rings.

In the areas they had access to, the grass is about 80% returned (edit: in about 6 months since we butchered them that is). They would not eat the deeper underground runners, digging them up and ignoring them. Everything else was eaten mind you, just not the tough grass runners

Strange. I thought pigs would knock out nearly anything short of shrubs or tree. If you try pigs again some suggestions to try. Try irrigating areas so they pigs can turn it into a mud hole Maybe that would get it soft enough for them to get deep enough. Then move the mud hole around by watering different areas. I know in our dry climate and heavy clay soil for them to get the field bindweed dug out that watering is essential. Otherwise our soil is so hard the pigs may as well be rooting at rock. My other thought is that even if they don't get the roots they should have suppressed growth long enough to have at least seriously injured the root so 80% popping back to life immediately makes me wonder if the roots were being supported by plants outside the fence? Maybe a deep spade around the perimeter as you are starting to cut all runners where they enter the fence? Realize in some plants that runner is 18 inches or so down. Might be worth digging a few test holes to see how deep you need to cut. Finally if the pigs didn't do it by themselves maybe tarp method of weed control following to continue to stress the roots into submission. Just don't ever let them rebuild their energy stores. You should be able to kill the roots through stress. Be sure you water well under the tarp. Here if we don't the plants will go dormant and hold. Instead you want them to have ideal growing conditions except starved for light so they grow good but can never rebuild their energy store.

They ate one of our shrubs down to the root ball and ring barked 3 trees (Gums, 20+ meters tall) but they would not eat the couch runners

We had them during the wrong time of the year, winter, so it was very wet, they had plenty of water holes and literally turned the flat ground into a something you could have made a rollercoaster park out of! Then the sun came out and we have a mountain range of clay they churned up.

We have had some good results with an area we let the pigs dig up, which we almost immediately placed cardboard over along with straw/lucern and some leaf matter. The grass there only encroaches from the edges (controlled by a ditch around the edge), everything in the bed is free of grass so it looks to be a multiple vector approach to controlling cooch, though initially we had hopped the pigs (and then geese) would be able to do it on their own it did not turn out that way.

(Hurm, thinking about it, one of the areas that has not grown back yet where the pigs had grazed had a tarp on it with some rocks, not to kill the grass, just storage... I'll have to try that again on a few other areas we are about to try and control, thanks for that information, especially the watering part!)

The fact that the grass was probably in its dormant phase for winter might have also affected how hard the pigs went after it. We only ever put pigs on stuff when it was in its growth phase in the spring and summer.

It sounds like you are maybe not familiar with using tarps for weed control. Anything that blocks light will work. We have used plastic tarps, canvas tarps, old carpeting, plywood to list a few. The cheap blue plastic tarps don't seem to be as good.(green or black and silver both seem to be fine) If you use a single layer of the blue ones you will notice the barest hint of green in the plants under it. My opinion is they leak to much light through. So double layer them or add something else like newspaper to the surface first then the tarp. Plants that sucker or travel by under ground runner are really hard to control with this method since the plants not under the tarp feed energy to the ones that are keeping them on life support. Our answer has been repeated mechanical tillage of the plants not under the tarp. I have had people tell me the white plants under the tarp should be broken off occasionally. They argue the damage costs the plant more. My feeling without proof is you want the plants as big as possible so they are consuming as much as possible while not adding energy to the system.(although I may rototill the whole area as I am finishing just to stress the plants that much more.) Learned the hard way if you use plastic be sure to water first. If the plants are too dry they go dormant and this is all wasted effort. Old wool carpeting is my favorite because it lets water through and is nearly immune to wind if it is kept damp. Some old all wool carpets you may be able to compost in eventually. The other carpets use till they start falling apart them take them to the landfill that was their original destination having gotten years of use out of them in the meantime. You might get 15 years or more out of indoor/outdoor carpeting if you are lucky enough to get some being removed somewhere. When it gets to holey to work by itself it is still an incredible tarp weight moderately protecting the tarp from both wind and sun damage and from damage from the real weights holding the tarp down.

No, we've not really done anything with using tarps for control (Other than accidentally)

1. I agree with pigs/dormant grass, sounds like that was the issue. We knew we had them the wrong time of the year but circumstances conspired against us and that was the only choice. Once we have finished our freezer/smoked pork we will be getting more, and this time during summer!

2. Thanks for the tarp information, it all sounds logical. We have been using cardboard, large sheets. I guess they are mimicking much of what a tarp/carpet is doing (though slightly less robust). Water can get through, giving the grass below good growing conditions but starving it of light.
We are also digging trenches around the edges so the grass under the cardboard is isolated.

Got some wok ahead of me it seems Thanks for the replies!