Orum T. V., Ferguson N., Mihail J. D., Saguaro (Carnegiea gigantea) Mortality and Population Regeneration in the Cactus Forest of Saguaro National Park: Seventy-Five Years and Counting, PLoS ONE, 2016, 11(8):e0160899, doi: 10.1371/journal.pone.0160899
Annual observations on six 4-ha plots during 1942–2016, except 1955. The authors describe episodic saguaro regeneration, age- and cover-related survival, and changes in height structure. Germination years of small plants were estimated from local growth data.