While researching the English Hawthorn, I discovered a new tree native to Vancouver - the Black Hawthorn. The Hawthorns are another member of the Rose family (remember the apple and cherry). The author of the Nature Guide I was using thinks that she left it off because it often presents as a bush rather than a tree.
The Ginkgo Balboa tree is fascinating because of its age. Flowering plants (including most deciduous trees) are the most evolved plant families of the plant kingdom. Mosses and other nonvascular spores are the least evolved. Between nonvascular spores and flowering plants, we find vascular spores and naked seed plants. Included in the naked seeds category is the conifer division and the single ginkgo tree, the only surviving species of the Ginkgophyta division. All other species in the division are now extinct. The Ginkgo tree is often called a "living fossil".