Yellow weed in lawn

Both our front and back lawns (and many of our neighbours lawns) have become infested in a weed which has small yellow flowers (its not trailing buttercup). We tried Evergreen complete but its still there.
Any idea what this is and what will get rid of it.

Thanks everyone

 

Evergreen complete only contains a weak mixture of herbicide as far as I know. There are herbicides (weedkillers) that act specifically on most weeds and leave the grass alone, such as Verdone.

Also, if you mow very regularly, the weeds should eventually go anyway, as they can't cope with continuously being beheaded, whereas grass thrives on such treatment so grows thicker. You get the double whammy of weeds being severely weakened by topping, and the grass growing stronger and thicker and thus out competing the weeds for the space.

 

It looks like it could be Birds-Foot-Trefoil. I have no idea how you would eradicate it in a lawn as I tend to let my lawns run riot with wildflowers.

 

See here for more info:
http://www.cvni.org/wildflowernursery/wildflowers/birds-foot-trefoil

 

It is lesser trefoil, commonly called yellow sucking clover. This stuff is prevalent in recent years and a pain to treat, in my experience granular feed and weed along with even the cheaper professional mecoprop formulations ie relay do not work on it.

Mowing regularly in the case of sucking clover will not work and will make the problem worse, it grows no more than around 1" from ground level so the mower blades hardly touch it, all you achieve is to weaken the grass and allow the damned trefoil to spread along with other weeds.

Verdone extra should work although Ive never used it on trefoil.

The products I use are professional use and kill the damned stuff in one hit, Namely Crossbar and Bayer Spearhead. The former is significantly cheaper and for lesser trefoil equally effective.

http://www.amenity.co.uk/webstore/product_info.php?cPath=1016&products_id=377

If you go down the route of the above then take great care to measure the dosing out carefully since it is a concentrate, you need to spray it with a good knapsack sprayer as well, with a flat fan nozzle.

Whatever you use, it pays to use a marker dye so you can cover the area accurately without missing areas, I use red marker dye and would suggest the use of this whatever you decide to use:

http://www.stantonhope.co.uk/Tools_26_Equipment_160105_Scarlet_Powder_Marker_Dye.asp

 

Heres a link with a good picture:

http://www.lawnweeds.co.uk/lesser-trefoil.html

 

You are right Paul, it is the lesser trefoil.

 

I have this on my front lawn..it is a pain..if I use this treatment Verdone,will the grass be affected ?.

 

cheers Andy..I have had a good look at the lawn and there seems to be more yellow clover than lawn, :(so it looks as I will have to live with it, or have a new lawn....

 

I'd treat it, then when I was sure it had gone, I'd give the lawn a good raking over, mix some lawn seed and sharp sand, and sprinkle it all over, especially on any bald patches that had formed.

 

Littleorme, No need to reeturf. You can overseed afterwards and the grass will soon come back.

 

Thank you both for your advice..the whole lawn is affected,so it looks as if I want a reasonable lawn I am going to have to use the remedy..and then overseed..Cheers