Question
Jim, in my yard we have a large[20 foot] brown spot,it  looks like the grass is dead.We also have large mushrooms growing in differt locations in the yard.Can you help?  Thank you,Dave

Answer
Hi Dave,

You did not mention what type of turf grass you have for a lawn; information here has been made more general for all types of lawns.

Mushrooms:

Mushrooms in the lawn are of no consequence or threat.  Use plastic gloves to pull the mushrooms from the lawn and dispose of them in plastic bags so they will not make zillions of spores to cause more mushrooms in the area. Dryer conditions and using less nitrate fertilizer will prevent future mushroom blooms.

Regarding Brown spots in lawns:

Given the basics of climate and an appropriate grass-type, enough sun-light, good to mediocre soil and so much water, all common turf grasses are easy to grow.  Add some extra water and an occasional nitrate fertilizing event,...  all common turf grasses are VERY EASY to grow. So, if you are having lawn appearance problems, suspect soil chemistry and physics causes or else some sort of disease or pest problem.

There are more than twenty popular grass types and they do vary in the particular needs, but most are easy to grow with basics provided.  All grasses like lots of sun-light and will need about 1-3 inches of water per week to do OK.

Several scenarios can cause an area of dead lawn.
IF you have a cool-climate grass-type such as Fescue, Rye or Bluegrass, the hot temperatures of summer combined with drainage problems of the soil or an inability of the soil to hold moisture will cause the symptoms you mention.

Working to improve the quality of the top-soil by adding better soils and humus will greatly help this type of cause.

An inexpensive soil-test kit from the garden center may also define certain soil chemistry problems which could be contributing factors.

Other than soil chemistry and physics causes and more rarely,...the turf grass could have become infected with a bacterium, virus or FUNGUS.  Of these only fungal problems have any cures now available.  Usually, you can simply take a closer look at the grass foliage and stems to actually see evidence of a fungal infection.  Below here are some links with more information about turf-grass diseases and treatments.  

Turf grass FUNGUS outbreaks are relatively common and often fast spreading.
Work fast to avoid losing large areas infected with the phytopathogen.

Visit this website and link to "Lawns" for IMAGES of many turf grass diseases and their diagnosis:

http://plantpathology.tamu.edu/Texlab/index.htm

BROWN-PATCH DISEASE Website: http://plantpath.unl.edu/peartree/homer/disease.skp/Hort/Turf/Tubrnpt.html
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A heat stressed BERMUDA and other grass type lawns with HIGH THATCH accumulation and over watering may  have a FUNGUS OUTBREAK.  Keep thatch removed and composted to re-cycle to the lawn's hot spots every year before the heat arrives; this improves the top soil and also adds to soil fertility.
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Fungi reproduce by microscopic SPORES.  As with weeds and their seeds, working to break the reproducing cycle by eliminating the spores and reproductive phase of the fungus is the best way to control it.  Rakes and tools, including the lawn mower should be sufficiently cleaned with a bleach solution to reduce the human caused spreading of the spores.
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If you can verify a FUNGUS DISEASE:
Your local garden center should have a variety of FUNGICIDE chemicals to treat a fungus infection of the grass.  Some fungal infections can spread very fast and destroy vast areas in short order so do not waste any time in treating a fungus infection once diagnosed.
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If a FUNGUS is ruled-out, look for insect pests above the ground and in the root-zone.
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With a good fertile-loamy well draining top-soil, best quality hybrid grass type(s), 1-3 inches of water per week, plenty of sun-light, an healthy root-zone ecosystem...almost anyone can have an excellent lawn with a minimum maintenance effort.

I Hope this has answered your question(s)!

___JIM Gibbs,
   Microbiologist

Visit my Lawn & Gardens webpage for more facts and links:
http://hometown.aol.com/eilatlog/lawnol.html

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