It's time to exercise your national park brain muscles again, with this Quiz and Trivia #9. See just how much you know and learn a little something at the same time.

The days of walking into a visitor center at Saguaro National Park and picking up a backcountry permit are numbered. Beginning in January, those permits will be offered only through recreation.gov.

Take saguaros out of Saguaro National Park, and you’d lose more than the park’s namesake cactus, one that gives skyward structure to the vista here. You might strain to catch the drumming of the Gila woodpecker, fail to catch an elf owl peering out from its cavity nest, and not know where to look for Lesser long-nosed bats. All these creatures rely on the saguaro for food and shelter. Realizing those possible losses to this Sonoran Desert landscape begs the question, "How are the park’s saguaros doing?"

A small number of entrance fee envelopes were stolen from an "iron ranger" fee station at Saguaro National Park in Arizona, prompting park staff to suggest that anyone who paid with a credit card contact their card company.