Fungus Amongus       (Click on photos to enlarge)

Overview of Area
Overview of Area
40% of the total group
Single

 
 


underside with dirt
after dirt washed off

side view of group

We've had growths like this about 4-5 times this year.  Usually happening after a long dry spell followed by a bit of moisture then several hot dry days.  Had the same problem for the past two years, but not as bad.  Each year the area because larger, but the center area recovers nicely from the previous year.

The closest thing I could find was something called "Black Tree Funge."
Gary passed a copy of your e-mail on to me and I took a look at the various photos on the "Fungus Amongus" web site you provided the link to.  As far as I can tell, what you've got there is Ganoderma lucidum, sometimes known as Ling-Chih or Varnish Shelf.  This is a wood-rotting fungus usually found above ground on living or dead hardwoods. 

Occasionally it occurs in lawns and similar situations when there is buried wood or roots.  If I had to guess, I would say that there are the remains of an old oak stump in the lawn in question.  This is not a poisonous fungus, but can cause white rot or butt rot on living trees. Let me know if you have any questions.

Peter Mullin
Department of Plant Pathology
University of Nebraska-Lincoln
406 Plant Sciences Hall
Lincoln, NE  68583-0722
(402) 472-5770
FAX: (402) 472-2853

 

http://www.forestpests.org/ash/varnishfungus.html