How to use the nuts and leaves of this “living fossil” 
My “Nuts and Berries of California” book is mostly about the wild nuts and berries that Native Americans used for subsistence all throughout this large state of ours. But because there are so many introduced plants in our urban areas, I included a short section in the book describing those ornamentals which are also useful for food or medicine. That section is called HIPs, for “horticulturally introduced plants.” I only included those plants in that section which have also survived well on their own, even in the wild. The Ginkgo tree is one of those HIP plants.
Botanists believed that the Ginkgo biloba tree was extinct, but then it was found in a Chinese Buddhist monastery in the 1700s, where specimens were being cultivated.
Once it was rediscovered, ginkgo has been cultivated and spread all over the world as an ornamental and street tree. It is popular because of its unique appearance, and its relative resistance to insects and disease. To Buddhists, the tree is regarded as sacred.
In Japan, and other parts of Asia, the processed nuts are added to rice and stir fry dishes. The nuts are high in protein and low in fat. The medicinal properties of the nuts, which you get by eating them, are said to include the release of stress and hypertension (the result of dilating blood vessels and increasing oxygen into the blood stream). The nuts are also reportedly good for pain and soreness, as well as aid to digestion.
Yes, I harvest the ripe ginkgo nuts, and yes, I have to hold my nose! The fleshy tissue around the seed really stinks! Some people have learned to not-mind the strong odor, generally reminiscent of fresh feces. Yes, you can get used to just about anything, and in time, you can learn to not be bothered by the “aroma” of the flesh around the ginkgo nuts.
My suggestion is that you just get over it, and it might help if you chew on some aromatic gum, like licorice gum, while collecting.
Once collected, you can let the nuts and their soft outer shell dry, which makes it significantly easier to clean. Or you can just clean them right away, as I tend to do. I always wash them outside. You can put all the fresh ginkgo nuts in a pan of warm water, and roll them around between your hands to clean off all the outer coverings, which you should then toss into your compost pile.
The cleaned nuts are then best dried, such as in the oven at pilot-light temperature. I have dried them with their shells, and without their shells. I don’t know if one way is right or wrong, and I believe it is just a matter of preference. However, the ginkgo nuts in the shell seem to keep a lot longer than the shelled and dried ones. If you plan to eat them right away, then it probably doesn’t matter how you prepare them.
Once roasted, you can just eat the ginkgo nuts as-is.
(Yes, there are two types of people: Those who like ginkgo nuts, and those who do not….)
I have never eaten these nuts raw because of the foul odor. There have been some reports that the nuts can make you ill if you eat them raw (no doubt!), and they must be boiled or roasted for about 25 minutes. You’ll know they are done when you can easily break the thin shell with a nutcracker. They taste is akin to a bean.
THE LEAF
When you see pills of Ginkgo biloba in the health food stores, they are made from the leaf. The leaf extract has been subject to many clinical tests, and it apparently increases circulation for the limbs and for the brain. This is apparently why it does seem to be helpful for improving memory and assisting with retaining memories. Suggestions that ginkgo can reverse dementia don’t seem to hold up to clinical tests. Nor do the claims that ginkgo can cure cancer seem to be valid, so far.
An extract from the leaf has also been found to improve the immune system, and to protect the heart by clearing plaque from the arteries. In fact, the extracts are used for many ailments such as headaches, asthma, kidney disorders, and more.
I have found that when I am experiencing a “slow day,” ginkgo pills, or homemade tea from the leaves, seem to offer a subtle yet noticeable “pick-me-up” without the eventual slowdown that follows drinking coffee.
There has been some debate about the safety of gathering your own ginkgo leaves for making your own tea. From what I have concluded, it seems safe enough to brew an occasional cup of tea from the leaves. Also, apparently the best time to collect the leaves for tea is when the leaves have turned yellow and are falling from the tree. This also apparently bypasses any toxic properties (e.g. ginkgolic acid) that may be in the leaf.
But most negative reactions from using ginkgo are not from the leaf, but from eating the nuts raw.
Ginkgo is a smooth-barked tree, often growing upright in a very vertical fashion when young, and then producing a much larger angular crown as it matures. Each leaf is fan-shaped, and has the appearance of a fern. The leaves turn yellow in the fall. The fruits, formed only on the female trees, are covered in a light brown fleshy coating that is very odoriferous. The nut has a thin shell that is easily cracked.
The tree is widely cultivated tree, planted as a street tree, in parks, gardens, and yards.
