Clark D. J., Clark T. O., Duniway M. C., Flagg C., Effects of Ungulate Disturbance and Weather Variation on Pediocactus winkleri: Insights from Long-Term Monitoring, Western North American Naturalist, 2015, 75(1):88-101, doi: 10.3398/064.075.0110
Twenty years of monitoring of one Pediocactus winkleri plot in Capitol Reef. Diameter, flowering, deaths, appearance of new plants and signs of disturbance by ungulates were recorded. Repeated trampling was associated with greater mortality and a lower chance of flowering. Relationships with temperature differed between spring stages. A small number of larger plants made a substantial contribution to flower production.