In the spring, the gray layers of the Yolo Formation form the bottom of the pools in this section of the creek. In the summer and fall, these pools have dried up, allowing you to inspect the bedrock. Shale is easily eroded by the action of water, so outcrops of the Yolo Formation are difficult to find in Cold Canyon. Cottonwood tree . Continue up the main trail.
Cottonwoods are important riparian trees, requiring water around the roots.
This is a good spot to watch birds. Wildhorse canyon . After crossing the stream, the trail climbs through dense stands of chaparral. When you emerge from the chaparral, you will have a good view of both Wildhorse Canyon in the distance and Cold Canyon close by. This wild area is owned partly by the University and partly by the Bureau of Land Management, with a few private inholdings.