by Rick Hartigan
photos by roni ziemba
Part 3 of a 7-part series...
Night. The last of the twilight fades. The movement at the top of the saguaros is imperceptible, but there is movement none the less. A few of the buds are opening. Slowly, ever so slowly, the petals peel back. Before midnight they are open. The white blossoms glow in the moonlight. The fragrance drifts on the breeze, beckoning the pollinators to their banquet.
Generous with its nectar, the saguaro waits, but not for long. Lesser long-nosed bats and Mexican long-tongued bats plunge their faces into the flowers to feast on the nectar within. Fitting the flowers like a key in a lock, their faces emerge well dusted with the heavy yellow pollen. They move on to other flowers, from cactus to cactus, feeding on the nectar in exchange for pollinating the state flower of Arizona. The pollinators must move from one cactus to another. A saguaro cacti must be cross-pollinated. Without the pollen of another saguaro, the flower’s promise will not be fulfilled and no fruit will be produced. Across the lower slopes of the Rincon Mountains, on and around Tanque Verde Ranch, thousands of saguaros await their turn, luring the bats with their sweet reward.
Dawn. As the promise of day shines above the mountains to the east, the bats return to their roosts, turning over their job to the birds. As the day warms, the Gila Woodpeckers, Mourning Doves and White-winged Doves visit the flowers, but their shift is shorter than that of the bats. By the afternoon, the flowers have closed, never to open again. Others wait their turn. Unlike the night-blooming cereus, not all the saguaro’s flowers bloom in a single evening. They will unfurl their flowers nightly in the weeks to come.