Galls Along the American River

My day off.  I got up early anyway (around 5:30 am) to head out to the American River Bend Park to search for galls… and it was already 70° outside.  The sun wasn’t even up yet and it was 70°.  Yuck!

I went early in the hopes of maybe seeing otters or beavers in the river before I went searching for galls, and I DID catch a glimpse of a beaver.  I was facing the sun, though, so mostly I just got silhouettes of him in the water.  I also got to see ducks, Great Egrets, Snowy Egrets, lots of big orb-weaver spiders, Scrub Jays, Starlings, Common Mergansers, Canada Geese, Wild Turkeys, some Green Lacewings (and their eggs) and some Eucalyptus psyllid bugs and their lerps.  The psyllid bugs produce honeydew and ants can often be found tending the lerps.

Of the galls, I got photos of Red Cones, Spiny Turbans, Pumpkins, Oak Apples, Hedgehog Galls, Yellow Wigs, Willow Rosette, and several specimens of the Flat-Topped Honeydew Gall.  The flat-tops look like tiny brown muffins and exude honeydew (like the psyllid bugs do).  Ants and Yellow Jackets can often be found feasting on the stuff… and there were lots of both at one tree I visited.  I also found a leaf gall on a Valley Oak that I haven’t been able to identify… and then came cross a willow tree with hug balls of sap hanging from it.  Those seemed weirdly out of place to me.  I’ll have to do some more research…

I was actually at the park for about 4 hours, and on the way back to the car, caught a glimpse of an adult coyote sauntering across the bank of the river.  ((I’d heard the coyotes yip-yowling at each other when I first came into the park, but didn’t see them.))

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Oh, and I found out that the oak leaf galls were created by the Rosette Gall Wasp (Andricus wiltzae), and not a lot is known about that species.

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Mary K. Hanson is an author, nature photographer and Certified California Naturalist living with terminal cancer.