Laura Kindsvater Oddly shaped, sack or tube-like flowers mark the blooming of California pipe vine , Aristolochia californica . Fungus gnats pollinate this plant, drawn by a metallic odor. The sepals of this flower are colored green or light brown with a lining of pink or red thickened tissue and purple veins. The leaves are heart-shaped. It's easy to mistake it for one, unless it happens to be blooming, and then its wispy, fluffy seed heads reveal its true identity as a relative of the common dandelion.
Mule fat grows along stream banks as well as in the creek.
Different species of willow are very difficult to tell from one another. There are at least four different species in Cold Canyon. They only grow close to or in the stream. Willows are famous in the ethnobotanical world for manufacturing the chemical compound from which aspirin was derived. The unusual flowers of this plant, made up of numerous, spirally arranged petals and sepals, are bright pinkish red and measure approximately 5 cm in diameter.