C. Biology:
Plants of Camissonia confertiflora have been collected in four years: 1952, 1991, 1997, and 2001. The number of plants in 1991 was about 50, with plants about 10 cm tall. Plants were observed but not collected in 1992. The number of plants in 1997 was about 20 with most about 6-10 cm tall, depauperate in size and number of blossoms. Plants had been unsuccessfully searched for during 1981-82, 1995, and 1996. The site was also visited in March 1999, but it was too early to document plants, which are known to bloom in late April and early May. Seeds in the cinder soils are more likely to germinate during calendar years that have between 12 and 15 inches of precipitation or in the spring after unusually wet winters. 2001 was a particularly wet winter. In April 2001, over 200 plants in one patch were observed in an area approximately 30 m long (the length of the cindery wash) by 15 m wide. The plants appeared to be a bit higher on the slope than observed in 1997 (Alta Hansen, pers. comm., April 2001). Plants were between 5 cm and 40 cm in height. The flowers were yellow, fading red. By mid-May 100 plants were observed in fruit, only 4-5 plants were still in flower and only a single flower persisted on these plants. They were found almost exclusively in a drainage wash in an approximate area of 30x80m. More plants were growing on the western side of the wash than on the eastern side. Plants ranged in height from 2 to 50 cm. The plant stalks were red in color with large, white, flat hairs toward the base. The fruit was straw color, the inner side of each capsule appeared iridescent (M. Koopman, pers.obs.2001).
The yellow petals have a basal area of the petal with a large, non-ultraviolet reflective area, with red dots near the base, fading purplish (Raven 1969:202). The red dots serve the same function as nectar guides. This is in contrast to other species in the section Chylismia that are strongly ultraviolet reflective. The non-ultraviolet-reflecting spot is invisible to the human eye but can be photographed with special techniques. The flowers open near sunrise or in the morning (not evening, as the common-name for the family suggests) and the flowers probably wither in less than a day. McClintock reported to Raven that the pollen of the type collection was shed in the middle of the day (Raven 1962). This suggests that the plants are out-crossers, pollinated by bees that may be oligolectic, gathering pollen from no other plants (Raven 1969). C. confertiflora is presumably self-incompatible, similar to C. brevipes, which is well-known to be self-incompatible (Raven 1969). It has been suggested that large flowers indicate out-crossing, while small flowers indicate self-pollinating or self-compatibility. It seems logical that plants that exploit or can succeed well in desert habitats should be self-compatible or autogamous. However, this has not been the case with many species of Camissonia. Raven (1969) suggests that the ability to adjust to the rapidly shifting desert habitats calls for a maximum of recombination - and that this feature is precisely what has favored Camissonia.
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