What is that light yellow ball on my lawn, I wondered.  Is it another black walnut in its green – yellow husk?  But a closer look revealed a puffball.  Mushrooms seem to be popping up everywhere this week.  Perhaps you have some in your own yard.

Mushrooms, the fruiting body of fungi, wait until the environment is right to spread their spores and start new fungi.  Wet, warm, humid weather is perfect for them, and we’ve had persistent damp, humid weather this past week.

I went back to photograph that puffball the day after I discovered it, but some animal had already eaten parts of it and scattered remaining parts around.  What eats mushrooms?  Rabbits and squirrels are my first thought, and I’ve got enough of both animals nearby to believe one of them is the vandal.  But insects, mice, slugs, some game birds, and even deer and bears may eat mushrooms.

Have you noticed that sometimes mushrooms appear in “fairy circles” or in lines?  That’s because mycelium is a network of fine one-cell wide fungi fibers that are invisible as they spread underground looking like a spiderweb.  Those circles or lines of mushrooms reflect the underground network.

That underground network is part of a symbiotic relationship between fungi and trees, often oak or beech trees, but other trees such as birch, willow and cottonwood also enjoy this relationship.  The tree provides carbohydrates to the fungi which in turns breaks down the materials to give minerals and nutrients back to the trees.

The puffball on my lawn reminded me of my childhood when my mother, finding a puffball, white and spongy, would cook and eat it.  I have never liked to eat mushrooms and cooking mushrooms didn’t help.  But aren’t some mushrooms poisonous?  Indeed, there are poisonous mushrooms, ones that can make humans very sick or die.  Some of them are close in appearance to edible ones. While animals seem to be immune to poisonous mushrooms, humans are not.  So unless you have a knowledgeable person teach you how to discern edible from non-edible mushrooms, it’s best to just look at them, not eat them.