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Blackbrush in the Granite Mountains in California reach ages exceeding 1,250 years. Blackbrush deter herbivores such as mule deer and desert bighorn with thorns and prickly branches, but it also has chemical defenses, and foremost among these are tannins.

Rabbit Valley is the last exit on I70 as you drive west through Colorado. It is in the McInnis Canyons National Recreation Area and it has several places to camp, so I decided to visit. But as I drove from I70 to Knowles Overlook on the Colorado River I was disappointed to see miles and miles of cheatgrass.

I first saw a photo of a sumac flea beetle posted by Steve Mlodinow in Flickr, a public platform to post photos and enjoy the works of others. I looked for the beetles, but had no luck until Steve told me exactly where to find them. I have now formed a search image and have learned to look first for evidence of herbivory—holes in the leaves and gooey clumps of feces.

While camping on the White River Plateau last weekend I was pleasantly surprised to find that a few of the aspen clones had turned from deep green to bright yellow. It occurred to me that the wonders of fall foliage raise yet a more mechanistic wonder: Why do aspen and other deciduous trees change color in fall?

Driving in to the Ponderosa Campground in Soap Creek, I was surprised to see a field of white flowers arranged in towers that seemed to mimic the dramatic spires in the cliffs on the other side of Blue Mesa Reservoir. I pulled over to enjoy the view and to capture it digitally. I walked among the flowers briefly, and I noticed many pollinators but no herbivores—nothing was eating the leaves or stems.