Figure 5 (in part) from Pierson & Turner 1998. Frequency of saguaros with and without flowers in 1993. Data are summarized by 0.25-m height classes. Open and closed bars are stacked to show the total number of saguaros in each height class. "We observed that plants on all aspects typically flowered when they reached ~2 m, as is the case for other Tucson populations (Steenbergh and Lowe 1977)."