GINKGO, MAIDENHAIR TREE
This ginkgo in Hayward, California, may be a cultivar.
Ginkgo is a gymnosperm, a highly unusual tree, ancient, and not closely related to anything else. From Wikipedia: "The relationship of ginkgo to other plant groups remains uncertain...no consensus has been reached. Since its seeds are not protected by an ovary wall, it can morphologically be considered a gymnosperm. The apricot-like structures produced by female ginkgo trees are technically not fruits, but are seeds that have a shell consisting of a soft and fleshy section...and a hard section..." It is usually propagated by hardwood cuttings, as seeds are slow and yield half male and half female trees. The male tree is grown exclusively because of the rank odor of seeds from female tree, although the inner part of the seed was roasted and eaten by the Chinese.
The deciduous, fan-shaped leaves are sometimes deeply bilobed, though that seems less the case in the photo above. Leaves are borne on little spur shoots, are light green in the spring, and turn gold in the fall, and tend to fall all at once. Branches are at 45° to the main trunk. Ginkgo can grow to be quite large, over 100 feet.
Ginkgo may be close to extinct in the wild in its original area in the mountains of China, but it is a beautiful specimen tree, long cultivated in China and around the world. It is an excellent street tree, resistant of most urban depredations. As well as being an ancient tree, ginkgo is long-lived to over 1000 years.
Commonly used in Chinese medicine, ginkgo is considered to be an antioxidant and improve blood flow to the brain. There are a number of health benefits attributed to ginkgo, but studies are inconclusive and/or contradictory.