Texas Gardening: Texas Native Plant Pictures by color ( Yellow ), 1 by htop

htop wrote:
Stemless Evening Primrose (Oenothera triloba), Onagraceae Family, native, winter annual or biennial, blooms February through April or February through July depending upon how far north its habitat is

Texas distribution:
http://www.csdl.tamu.edu/FLORA/cgi/vpt_map_name?reg=2,4,5,6,...

Stemless Evening Primrose can be found in clay or dry limestone soils of the Blackland Praire, Rolling Plains and Edwards Plateau Regions in dry open areas with drained soil such as barrens, prairies, floodplains, slopes, hillsides, rock outcrops in fields and grassy areas. It is a frequent lawn invader. The plant forms a rosette shape like a dandelion with broadly lobed leaves low to the ground. Because it is very low growing (usually 8 inches tall or less), it withstands mowing very well. The up to 4.5cm (1.75 ") wide flowers are bright yellow when they open about half an hour before sunset. When they close about noon the following day, their color has faded to a pale yellow. If you observe them opening, you will be surprised. They go from buds that resemble little okra pods to flowers in about a minute. This is so fast that you actually can see them move. The seedpods form at the base of the flower stem and are hidden in the foliage at ground level. They resemble tiny pinecones. Deer resistant is high. This hardy perennial is a good plant for rock gardens.

For more information, see its entry in the PlantFiiles:
http://davesgarden.com/pf/go/55461/index.html

The rosette bearing blooms shown in mid-March: