Texas Gardening: Texas Native Plant Pictures ( Aquatic & Bog ), 1 by htop

htop wrote:
Shrubby Water Primrose, Mexican Primrose Willow (Ludwigia octovalvis), Onagraceae Family, Texas native, perennial, blooms July through November, bog plant

Cross-referenced in Texas Gardening: Texas Native Plant Pictures by color ( Yellow )

It grows in wet soils or the mud of ditches, fields and rice fields, as well as the edges of marshes, ponds and streams. The plants are often found in large colonies and may reseed prolifically. The 1 5/8 to 2 inch, bright yellow, 4-petaled, 4-sepaled, stalked blooms appear from July through November from the upper leaf axils. The fruit are long, slender, erect, cylindrical, 4-sided, several ribbed pods that are up to 2 inches long. They are quite lovely and are often used in flower arrangements. The shrubby water primerose is a host plant for the water-primrose hornworm moth and is a favorite of swamp dragonflies.

For more information, see its entry in the PlantFiles:
http://davesgarden.com/pf/go/62774/index.html

A view of the base of a plant growing along a drainage ditch in Bexar County ...