Experts tackle readers’ garden questions.
Q: I have some kind of growth that I’ve been finding in my backyard for a couple of years. They usually appear under a large juniper bush and oleander bushes near the edges. They are usually about 7 to 8 inches in diameter when I have noticed them. This particular one, I found right next to my grandchildren’s slide and swing set, which is a new area. They don’t seem to be a fungus but I’m not an expert by any stretch. They are fairly hard to dig up and seem to be composed of a fine dirt as though some creature has built them, however I never see any bugs in or around them when I dig them up. Any idea what they are? They scare me!
Nan Wilson, Sacramento
Sacramento “Bug Man” Baldo Villegas: What Nan Wilson is seeing are mushrooms that probably are growing from dead or decaying roots from her juniper and/or her oleander bushes. I am no mushroom expert so I cannot identify them (from submitted photos).
In order to properly identify them, Nan needs to send pictures of the newly emerged mushrooms. Better yet is to take a sample of the fresh mushrooms to the California Department of Food and Agriculture Plant Pest Diagnostics Laboratory at 3294 Meadowview Road, Sacramento. The CDFA Lab has personnel that are very familiar with common mushrooms that grow in our backyards.
I use a lots of horse manure (from my neighbors’ horses) and wood chips from tree service companies in my garden as mulch and I see a great deal of mushrooms that grow in heavily mulched areas. I have seen a few mushrooms that look like puffballs very similar to Nan’s mushrooms.
Once they get old, the puffball mushrooms deteriorate and the inside of the mushroom contains millions of tiny spores that become airborne if one steps on the old mushroom. This is how the mushroom disperses and becomes widespread in my yard. So the “black dirt” that Nan mentions are the mushroom spores.
Nan mentions these mushrooms growing near her grandchildren’s slide and swing set. Until I get a positive ID on the mushroom, I would remove the mushrooms with a shovel and tossing them in the trash can for safety reasons as some mushrooms are known to be poisonous if handled or eaten.
Baldo Villegas is a retired state entomologist and master consulting rosarian.
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