Fairy rings GWF351
Updated February 2009
Despite their romantic name, fairy rings can look unsightly. They are caused by a fungus
that competes with grass for water and nutrients.
Q What exactly are fairy rings? Q If toadstools appear in circles the soil. Adding a lawn fertiliser to
without lush grass, is the fairy- the whole lawn will green it up,
A The term fairy ring is used to ring fungus to blame? hiding the rings.
describe the visible effects of
particular fungi growing in lawns. A There are other species of fungi, Q Can I prevent a fairy ring
All affect grass growth and some such as Mycena and Coprinus, that from spreading?
also produce toadstools. The rings can grow in lawns. Some of these A Fairy rings occurring close to the
are formed as the feeding threads may grow in rings, but without the edge of a lawn will gradually die
(mycelium) of the fungus spread peripheral lush, green grass out, as the fungal threads have no
outwards from the point of characteristic of Marasmius new turf to infect.
infection in ever-widening circles. oreades. The toadstools of Mycena If an affected spot is really
Q What damage do fairy rings are short-lived and disappear precious, the turf can be cut out
quickly. and replaced. But you’ll also have
cause in turf?
These are likely to be feeding on to remove soil to a depth of 50cm,
A Affected areas of grass die, due woody, decaying organic matter, and to extend removal of turf and
to direct competition with the such as tree stumps, the rotting soil to at least 30cm beyond the
fungus for moisture and nutrients. roots of trees that have been felled, outer ring of infection. Infected
The dense fungal mycelia, which or the remains of old shrubs. In soil and turf should be disposed of
grow to a depth of 20-45cm, order to prevent toadstools of these before replacing with a fresh
prevent water penetrating the soil. fungi, it is advisable to dig the supply. The vegetable plot will not
The fairy-ring fungus also woody material up and replace the come to any harm if the surplus is
stimulates grass growth at the turf during the autumn or winter. mixed with soil there.
periphery of the infection, Q What should I do if my turf is Q Are there any chemicals for
resulting in rings or bands of lush
infected with fairy-ring fungi? the control of fairy rings?
grass.
Q When are the symptoms of A Any toadstools that appear A There are no chemicals available
should be raked off and disposed of to gardeners for the control of fairy
fairy rings likely to be seen?
before they have a chance to rings. However, there are
A Fairy rings are composed of spread their spores. If infections are chemicals available to landscape
three zones. During the summer, recurrent, the mower should be contractors which require trained,
the outer and inner rings are washed down with disinfectant licensed operators to be used
marked by lush, dark-green grass after mowing the infected area and safely and legally. These
and the middle zone of grass will the cuttings disposed of. professionals will have the correct
be brown or dead. The slender, If fairy rings are spotted before safety equipment too, so it might
brown-capped toadstools of the the grass in the middle ring of the be worth calling them in if fairy
fungus Marasmius oreades, the infected area dies, the water- rings are a persistent problem.
most disfiguring of the fairy-ring repellent effect of the fungal Look on www.which-local.co.uk
fungi, appear in summer and threads can be eased. Irrigate the
for landscapers and specialists near
autumn, particularly during periods affected area with water containing
you. All companies mentioned on
of wet weather. The ring of a few drops of a mild liquid
the site have been recommended
toadstools marks the outer part of detergent, which acts as a wetting
by Which? members.
the area infected. agent helping the water penetrate