In August of 2005, brilliant yellow cones began appearing in the backyard of my house in Tucson, Arizona. The cones were perhaps three inches in diameter and about an inch high.
And they were made of flowers. And they were each in top of a Dorymyrmex insanus ant nest.
Dorymyrmex insanus is a very common ant, especially in open places like our yard. The Palo Verde Trees had bloomed recently and dropped their flowers, leaving bright yellow snow drifts of spent blossoms on the ground.
The ants had collected the flowers and piled them onto their nest mounds. Dorymyrmex insanus nests are usually just conical mounds of dirt.
Why did the ants do this?
I don’t know. Perhaps they were bringing the flowers back to the nest so they could better lick off any residual nectar from the flowers? Maybe they brought the spent flowers back to the nest as food, but then discarded the flowers as too large to bring into the nest?
The flower mounds lasted about a week, then then the Dorymyrmex returned to their usual dirt-mound nests, their flirtation with wild colors over.
