DBG Mirabilis rotundifolia Demographic Monitoring

This data set is derived from a monitoring study of Mirabilis rotundifolia that was conducted from 1993 to 1999. Individual plants within 15 circular plots (radius = 5 meters) were tagged and revisited. Plant height, plant diameter at the widest point, the number of buds, flowers, and fruits were measured. Plant description: Small (.5-4 dm) and variously branched perennials, dying back to ground level in winter. A single population may contain individuals with one or two stems as well as nearly hemispheric individuals with many branches. Leaves are leathery and exhibit a wide range of hairiness, but the plants are never completely without hairs. Lower leaves are round in outline, upper leaves are more pointed (egg-shaped to lance-shaped). Flowers are bright magenta and flared to approximately 2 cm. in diameter. The flowers are only open between dawn (or perhaps earlier) and about 10 or 11 am during the month of June. The small oval fruits develop in a papery, umbrella-shaped structure with breaks off and rolls or blows away when the fruits are mature. Plants are associated with, platy shale in the Arkansas valley, between Canon City and Pueblo. Purpose of the study: This study is the result of a cooperative relationship of Halnam, Inc., the Nature Conservancy, and the Denver Botanic Gardens. The study as aimed at investigating the life history and population biology of Mirabilis rotundifolia. Mirabilis rotundifolia is particularly threatened due to the close proximity of its populations to Halnam inc. The study should determine the effects that Halnam inc.’s practices are having on Mirabilis rotundifolia, and should determine what aspects are crucial to the long term health of the plants.