The frequent, heavy rains
in certain areas of the state have resulted in the appearance of mushrooms in
home lawns and landscape beds. Although mushrooms are often spectacular in size
and color, most are relatively harmless to plant life.Some of these mushrooms are associated with
arc-like or circular patterns in turfgrass called fairy rings. The ring pattern
is caused by the outward growth of fungal mycelium. The mycelium forms a dense,
mat-like structure in the soil that decomposes organic matter. This
decomposition releases nitrate into the soil, which in turn stimulates the
growth of the grass at the outer portion of the ring. This results in a dark
green appearance of the grass at the margin of the ring. Unfortunately, the thick fungal mat formed by
the fairy ring fungus interferes with water infiltration. The fungus also may
release certain byproducts that are toxic to the turf. This can lead to dieback
of the turf close to the ring. Fairy rings are difficult to control. You can
sometimes eliminate the ring by digging to a depth of 6 to 12 inches and 12
inches wide on both sides of the ring, refilling the hole with non-infested
soil. Or you can try to mask the symptoms by fertilizing the rest of the lawn
so that it is as dark green as the ring. This often isn't a good idea because
it tends to promote other turf problems. Commercial people can use certain
fungicides to control fairy rings but these products are not available to
homeowners. See http://www.ksre.ksu.edu/bookstore/pubs/EP155.pdf for more info on these fungicides.
Some mushrooms in lawns are not associated with
fairy rings. These may be mycorrhizal (symbiotic association with tree roots)
or saprophytic (live on dead organic matter such as wood, etc.) in the soil.
Because some of these mushrooms are beneficial, you don't really want to kill
them. Besides, a fungicide spray to the mushroom itself does little good.
Remember the mushroom is simply the fruiting structure of the organism. Most of
the fungus is below ground and inaccessible to the chemical. If mushrooms are a
nuisance, pick them and dispose of them as soon as they appear. Also, remove
sources of large organic debris from the soil. Also, mushrooms tend to go away
as soil dries. Patience may be the best control.Some of the mushrooms in
the lawn are edible, but others are poisonous. Never eat mushrooms unless you are sure of their identity. (Ward
Upham, Extension Associate)
Comments
Post a Comment