There are about 10,000 species of mosses which were classified with the Liverworts and Hornworts, but the latter are now in a their own divisions. They are bryophytes which means they do not have a vascular system. They are a common dweller in the lawn, encouraged by our damp climate. In the woodland garden it forms a beautiful carpet and is used extensively in Japanese-style gardens. The 19th century garden writer, James Shirley Hibberd, advised that moss was essential for inclusion in the lawn so as not to bruise the elbows when rolling on the grass!
It is ever-present as the spores float around in the air, invading the grass sward when the fertility is low and the soil is wet.

Keep the lawn well fed and don't cut it too short. Improve the drainage by pricking or spiking. Brushing coarse sand over the surface after spiking helps to keep the new pores open. Scarifying can help to spread the moss if it is growing actively, so it might be best to kill it first. This is done with a chemical treatment like Dichlorophen, a weed-and-feed treatment or Lawn Sand. The latter contains Ferrous Sulphate which can be obtained form hardware shops in powder form and is watered on at a rate of 6g per m². When the moss is blackened and dead use a spring-tined rake or a mechanical scarifier to remove it. An electric or petrol driven form of the latter can be hired, depending on the size of the job. This will only give temporary removal as the problem will return if the cause is not remedied, ie. relieve compaction, improve drainage and don't cut the grass too short, especially at the end of the season. An autumn feed with a low nitrogen fertilizer will also strenghten the grass to help it through the winter.
On flowerbeds a good time to remove it is after a frost which will have lifted it and it is easily gathered from the surface. Maintaining a loose dry mulch with a hoe on open soil, keeps moss away. Any sort of applied mulch will eventually be invaded in shaded moist areas.

Sometimes the moss is accompanied by Dog Lichen which grows as greyish, flattened scales. See also Pearlwort, a compact mat-forming weed often mistaken as Moss.

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