NE corner of William and Garden Way

Interior live oak

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California black oak

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Oracle oak

Oaks of the same evolutionary lineage hybridize readily in natural settings and some occur often enough to be given a name. Oracle oak is the best known example in northern California. It is a cross between California black oak and interior live oak.  In this neighborhood there is a black oak not too far away on the bike path, but no interior live oak near by, so the tree must have been propagated elsewhere and planted here.

The foliage, form and habit of a hybrid can vary widely, sometimes more like one parent and sometimes more like the other. This particular tree is fully deciduous like its black oak parent, but another might retain leaves through the winter like its interior live oak parent.