I have a lawn - about 80 square metres - and its taking me ages to remove all the weekds. These weeds are the long stringy type of weeds and the problem is that the roots are never pulled out. Perhaps I could dig the roots out but this would take a long time and hard work.

Does anyone know of something to do to kill these weeds without killing the grass?

To my knowledge there are no selective weed killers in Thailand for treating lawn weeds ... after reading your post about your water bill, I would cut out or cut down, watering your grass areas...

Make sure these weeds you have do not go to seed, as the problem will persist with those seeds germinating.....

Hard to say without seeing images whether you have annual or perennial weeds in the lawn.... Perennial ones will be harder to eradicate.... either way do not allow them to bloom and seed...

We had that problem with our new sod three years ago. If you don't mind using Paraquat, make a dilution and lightly wet a small rag with it. Wear long rubber gloves and apply it only to the leaves of the weeds. Obviously, you don't want to drip any dilution on the grass. The Paraquat will go through the plant to the root system and kill the weeds. Just make sure you use all the recommended precautions as the chemical needs to be used with caution.

We had that problem with our new sod three years ago. If you don't mind using Paraquat, make a dilution and lightly wet a small rag with it. Wear long rubber gloves and apply it only to the leaves of the weeds. Obviously, you don't want to drip any dilution on the grass. The Paraquat will go through the plant to the root system and kill the weeds. Just make sure you use all the recommended precautions as the chemical needs to be used with caution.

I did not want to mention paraquat, since there is no antidote to it... .... It will only kill annual weeds.... and only the top of perennial weeds (not the roots unless young plants).... except possibly with repeated use....on perennial weeds....

That why it is important to know what one is trying to treat.... (annual or perennial weeds) .... One could use the same method you mention with Round up, using rubber gloves and diluted correctly,,,,... as long as plants not ready to seed, as it takes a while to work! (10 days to two weeks) .

We had that problem with our new sod three years ago. If you don't mind using Paraquat, make a dilution and lightly wet a small rag with it. Wear long rubber gloves and apply it only to the leaves of the weeds. Obviously, you don't want to drip any dilution on the grass. The Paraquat will go through the plant to the root system and kill the weeds. Just make sure you use all the recommended precautions as the chemical needs to be used with caution.

I did not want to mention paraquat, since there is no antidote to it... .... It will only kill annual weeds.... and only the top of perennial weeds (not the roots unless young plants).... except possibly with repeated use....on perennial weeds....

That why it is important to know what one is trying to treat.... (annual or perennial weeds) .... One could use the same method you mention with Round up, using rubber gloves and diluted correctly,,,,... as long as plants not ready to seed, as it takes a while to work! (10 days to two weeks) .

I agree with you on that. I think I know the weeds the OP is referring to as they have runners that propagate the plant. I luckily only had to apply it once and it did the trick quite well and then the sod got more established. I see the local farmers spraying it on windy days and I wonder what the health effects must be on them being exposed to that mist for hours.

My wife has been fighting the same weed in our yard for years. I would try cutting your lawn, pulling all the weed you can get to then let your grass grow long. Here you hay have to pull some different weeds. Do this a couple of times. There after alternate cutting you lawn short a couple of times and let it grow to seed. The weed you are describing like to creep along on top of short grass, by letting the grass grow you will knock it back. Most weeds (broadleaf) can be taken care of by keeping your grass cut short (this keeps the weeds from seeding). I also would not be afraid of using a broad leaf weed killer (carefully) just to see what happens (maybe try it on a small patch).

My wife has been fighting the same weed in our yard for years. I would try cutting your lawn, pulling all the weed you can get to then let your grass grow long. Here you hay have to pull some different weeds. Do this a couple of times. There after alternate cutting you lawn short a couple of times and let it grow to seed. The weed you are describing like to creep along on top of short grass, by letting the grass grow you will knock it back. Most weeds (broadleaf) can be taken care of by keeping your grass cut short (this keeps the weeds from seeding). I also would not be afraid of using a broad leaf weed killer (carefully) just to see what happens (maybe try it on a small patch).

So what selective broad leaf weed killer is available here? I have never come across one... as you would in western countries....

I agree with what you say about letting the grass go to seed, providing of course there are not weeds to seed at same time! ..... Or take plugs of good grass and fill in holes, as it fills in fairly quickly .... depending on season of course (moisture needed) ....

I would ask at a farm supply store. I know we have bought stuff for corn and I am pretty sure there is stuff for rice. Like I said, test a small area to see what happens and when you let your grass grow out kill any tall weeds.

Also, I would let the clippings sit after you cut to act as a sort of mulch, your grass will come up through it before the weeds will.

Here is the culprit.

Here is the culprit.

CYMERA_20140405_171845.jpg

Well the problem here is that it is another type of grass, so there will be no "selective weed killer" to get rid of it....

You could apply some Roundup, by carefully dabbing each type of grass like that, ... even if you hit some of the good grass it will fill in again....

The lawn may look like a female dog has pee'd on it for a while... but long term, perhaps the easiest solution... The grass you want will grow back, or you can make some grass plugs, after a few weeks and fill in the dead spots..

It is going to be tedious.... but sometimes things in the garden are!

My solution as an ex pro: spray off the lot with Glyfosat and start again if this disturbs you. You will have the same problem again as the seeds germinate in a year or two.

We've had that stuff too. Pull as much as you can, hit any new stuff with roundup (very selectively), and let your other grass grow out to seed.......repeat.

My solution as an ex pro: spray off the lot with Glyfosat and start again if this disturbs you. You will have the same problem again as the seeds germinate in a year or two.

Sorry but I don't understand. DO you mean to get this Glyfosat and spray the whole lawn?

You have what appears to be a variant of "Bermuda Grass". Round-up will not work. I'm not sure what is available in Thailand to kill it. I'll need to research it.

Here's what you need but I'm not sure if you can get it in Thailand.

http://www.bayeradvanced.com/lawn-care/products/bermudagrass-control-for-lawns

Just for reference it is used on golf courses.

Glyfosat AKA Round up will work on this grass ...

If you don't have a lot of this weed grass already, try the method I mentioned above first.... But make sure to cut off seed heads first... In other words cut grass first and if very short, allow a bit of time for it to grow back..... Roundup, is absorbed through the green part of the plant (grass in this case) but takes a while to work...

If you have a lot of this weed grass, do as Cooked suggested and start the lawn over again.... If small areas need patching make your own plugs of grass to fill in the holes... or buy some new pieces of turf and make some plugs with that... . (make sure it is the same kind!)