It's lichen - means your lawn is neglected, lol! You need to aerate by spiking it all over (use a garden fork, push the tines into the ground and then pull it out, do it every nine inches or so, all over) and making sure you feed it this year. First month for feeding is April, and you can use a combined Weed Feed and Mosskiller preparation then, or you can just buy some mosskiller on its own now and apply it to get rid of the lichen immediately. Cheaper to wait and do it all together in April, but its up to you.

Hi markus I brought an old electric scarifyer from a second hand tool shop and have a good go at my lawn.it's a lot less back breaking than using a rake.

I can see that you have a lot of moss, me too! I got 2 big pop up bins full out of the lawn last year, and with all the wet weather we are having at the moment I think it will be really bad again this year.

Good luck at zapping that lichen.

A useful tip for reducing moss is to raise the blades on your mower. The longer grass competes better with the moss and really does reduce it, though it doesn't get rid of it altogether.