A distinctive trademark of the rocky uplands surrounding the San Gabriel River is Shin Oak (Quercus sinuata var. breviloba). This tree goes by a number of different names, including Shin Oak, Bigelow Oak, Scrub Oak, Scalybark Oak, Bastard Oak, and White Shin Oak. A small but beautiful tree, it commonly reaches only 10 to 12 ft in height, although occasionally larger trees of 20-30 feet in height can be found. Multiple stems of Shin Oak are usually found within a few feet of each other, the stems twisting upward in strange and interesting shapes. Its large multi-lobed leaves are light green in color, presenting a delightful contrast to the dark green foliage of the junipers among which it typically grows. The most distinctive characteristic of Shin Oak is its light gray, shaggy, and peeling bark, the origin of one of its other common names—Scalybark Oak.
Hiking the Good Water Trail, I often encounter Shin Oaks scattered among the junipers and live oaks. When I first observed these small trees, I wasn’t sure of the species. Their large, lobed leaves suggested they were part of the white oak group, and their scaly bark and multi-stemmed growth forms eventually revealed their true identity. I love seeing these small and interesting trees as I explore the bluffs and ravines that overlook the San Gabriel River.
