My two year old daughter showed this bug to me while we were visiting the zoo!
Red cone gall wasp on valley oak
Maybe Sphaeroteras trimaculosum?
California Gall Wasp on Valley Oak
Added a third photo to show the scale, which makes it look between 1/3 and 1/2 of my index fingernail long.
Lovely red berries on a flowering plant next to Donner Lake.
Small beetle perched on a plant very close to Budd Creek. Its iridescent elytra caught my eye in person, but I didn't manage a very sharp photo.
Golden-mantled ground squirrels and marmots were abundant up here. My two year old daughter saw the fluffy tail on a marmot and thought it was a cat.
Five petaled pale yellow flowered plant growing at higher elevation at the base of Cathedral Peak. Maybe a Ranunculus of some sort?
Holes leading underground to an ant hive. The collecting end of their trail followed mine for at least 100 feet before disappearing into the foliage. Many carried large light colored seeds or other plant parts.