Grasslands – From the beginning of the canyon between mile markers 0.0 and 3.4, there are rolling grassland hills. Gradually, blue oaks begin to make their appearance, and will gradually thicken to form expansive woodlands on the shadier side of the canyon. On the drier, south-facing slopes, chaparral vegetation takes over.
Riparian – Fremont cottonwoods and willows make up the dominant vegetation all the way up the canyon along the streambed. The cottonwoods eventually fade out at the campgrounds. Where cattle have access to the streambed, few young trees can be found.
Woodlands – Moving upslope from the stream, depending on the soil conditions, elderberry, buck brush, tree tobacco, bush monkey flower, Indian paintbrush, and yerba santa often fill in the spaces in between the oak trees. In the shadier spots, California buckeye become numerous, while on the drier slopes, Western juniper and gray pine appear. On the driest slopes, chamise and yerba santa make up the dominant vegetation in the chaparral habitat.
Chaparral – Starting at mile 3.0 on the north side of the canyon, the hottest and driest conditions, chamise, Yerba Santa, bush monkey flower, happlopappus, and the occasional blue oak and gray pine form thick, impenetrable stands of scrubby vegetation. This chaparral occurs all the way up to mile 20.7, where stands of manzanita take over.
For the flower admirer, the pull-out at marker 11.8 is a great spot to check during April. Just before the cattle guard, go up the steep slope on the left about 60 feet to the little knoll. Avoid walking through the middle of the knoll. There may be lots of purple owl’s-clover, goldfields, allium, evening snow, shooting stars, larkspur, and California poppy. At different spots along the next two miles, farewell-to-spring and Brewer’s clarkia are scattered along the loose shale slopes.