Long-term drought and near-term heat wave take toll on Arizona's desert ecology

Aug. 9, 2023
A person squats in the desert looking at plants on brown soil, with power lines in the distance under a blue sky.

The Tumamoc globeberry was initially discovered in 1908 on Tumamoc Hill in Tucson, Arizona. The plant grows in small, isolated populations, which makes it vulnerable to disruptions. Ecologist Frank Reichenbacher has been following the plant for about 41 years. The populations "hit the skids" in the 1990s and have dwindled since, according to Reichenbacher.

Frank Reichenbacher

Frank Reichenbacher worries it will soon be over for his Tumamoc globeberry — a rare Sonoran desert vine that features a fruit that looks like a tiny watermelon and tastes like dirt. 

For 41 years, Reichenbacher, an associate researcher at the University of Arizona’s Tumamoc Desert Lab, has followed the same three patches of the rare plants in southern Arizona — including one on Tucson’s Tumamoc Hill. 

The number of Tumamoc globeberry plants has dwindled over the past two decades. An old shade tree toppled last month at one of his sites, and he thinks the recent heat wave — which sent temperatures in Phoenix above 110 degrees for 31 straight days — might do in the rest of his plants.  

“Every time I go to my three little populations, I’m thinking, ‘Will this be the last time I visit?’” Reichenbacher said. “It’s been a long time since we’ve had a drought this hot, this deep and this long throughout the Southwest.”

It’s not just the globeberry at stake. Ecologists are concerned the heat wave is pushing some of the plants best adapted to the region’s hot, dry summers past their limits. There are early, concerning signs that the plants that symbolize the Southwest — like saguaro cacti with their iconic arms — have begun to die in some locations as the heat wave punctuates a megadrought that has gone on for about two decades. 

Read the full article on NBC News >>