Quercus engelmanii x castaneifolia | East Palo Alto
Here we see the leaves of an Engelman Oak hybrid in East Palo Alto, adjacent to the 101 Freeway. This tree also originated from Calaveras Nursery, and, again, was grown from Shields Grove Engelman Oak acorns. Remembering the leaf array from the Santa Rosa Plateau, it can easily be observed that this leaf morphology exists outside the normal leaf range of Engleman Oak. The leaf-edge serrations derive from the paternal parent, in this case almost certainly Q. castaneifolia.