Wild Sorrel

We have about half and acre of meadow grass which includes the above.  Although weather permitting it is cut on a regular basis this particular weed spreads like mad - any idea's on how to get rid of it would be appreciated.  I am afraid that clearing the area is not a possiblity.  Asperge.

You will need a selective herbicide. Grazon is one I have used successfully but you need to get it from a commercial horticultural supplier. It contains triclopyr as the active ingredient. 

If you can't get hold of it, Verdone extra has the same ingredient and is available in any garden centre. 

It will kill the sorrel and not the grass, but it will kill other broadleaved wildflowers as well. And the ground will be full of seeds. Fortunately they don't have a long life, one or two years. Dock seeds can survive for 100 years!!

Thank you Gold1locks for your advice on Sheep/Common Sorrel, that is the bane of my life.  We have been here 8 years and it is still very rampant, but will try your advice, if I can get hold of the mentioned Herbicides here.  Asperge.