Photo: Diane Edwardson, May 1, 2015. Friday, we noticed a rather large (4" tall) mushroom had sprung from the earth adjacent the Corralitas Public Staircase. (Click on photo to enlarge.)
The homeowner adjacent the public staircase recently landscaped the area next to the stairs. So we don't know if the mushroom hitched a ride in the plant nursery pots, potting soil or mulch. Perhaps it had a foothold on the slope and escaped detection in years past, due to the fact that brush clearance on vacant lots was rarely done before July 1.
Earlier this year, we documented a smaller version of what appears to be the same species, a few hundred feet up the street.
*UPDATE 5-5-15: Identified. Thanks to Michael Wood at MykoWeb, to whom I sent the mystery mushroom posts: Agaricus deserticola (AKA Longula texensis) are adapted for dry climates.