This week’s plant for #WildEdibleWednesday is Ginkgo biloba, otherwise known as, well, Ginkgo biloba. This one is more for all you urban foragers, as it’s rare in this country to see it growing outside the confines of civilization, although it does happen. Pretty much all of us have probably heard of it as a nutritional supplement to boost brain function and improve memory, but what else is it good for? Well, read on.
Ginkgo is the truest definition of a living fossil. Like Sassafras last week, it’s old. Really old. The earliest fossil records put Gingko species as emerging 270 million years ago during the Permian period, which means they pre-dated the dinosaurs. This makes it unequivocally the oldest deciduous tree species still living today. And it shows it. In some ways, it has more in common with cycads, ferns, and mosses than it does modern deciduous trees. The species is dioecious, meaning there are male and female trees. It doesn’t produce pollen per se, its male gametes are much more like spores instead. At one point, it was one of the most common trees on earth, covering vast swaths of the temperate continents, if the fossil records are any indication. But over time (especially since the end of the last ice age), Ginkgo’s range has steadily decreased until the present day, and it’s now considered endangered in the wild, growing only in two isolated areas in southern China. And it’s also the last survivor in its family – there were once dozens of species in the genus Ginkgo, but G. biloba is the last remaining one. While it’s ancient as a species, it’s also incredibly long-lived as an individual tree. There are specimens in China and Japan that are verifiably recorded to be over 2,500 years old. It even has a sort of prehistoric look to it, with short, stubby limbs that go in all directions and a thick trunk for its height. Ginkgoes, although slow-growing, can get quite large. Trees over 100’ tall are not uncommon. Ginkgoes are entirely unique, and have no mimics, toxic or otherwise. They have distinctive fan-shaped leaves with veins that radiate out from the stem like rays, and are occasionally notched in the middle and divided into two lobes. (Hence the scientific surname biloba.) Those same leaves are one of its main draws as an ornamental tree… they’re an attractive green during the summer, but in the fall, they’re really a sight to behold. Ginkgoes change color quickly and dramatically (often within a few days) and are a rich, golden yellow. The bark is light brownish-gray and smooth on young trees, and dark brown (almost black) and deeply grooved on mature trees. Ginkgoes flower in mid to late spring, bearing cones and ovules (on male and female trees, respectively) that look almost identical to pollen spurs on pine trees. In mid to late summer, the female trees set egg-shaped fruit, which are 1”-2” long, fleshy, and smell absolutely awful. These things are rank, and smell either like spoiled butter or straight-up vomit, depending on who you ask. They also contain a chemical that can cause contact dermatitis in folks with sensitive skin. So if it’s rare in the wild and not even native to this continent, why are we talking about it as a potential edible and medicinal tree? Because for the past several hundred years, it’s slowly spread back across the globe as a cultivated landscape tree. Ginkgoes, while extremely rare in their native range, can now be found on all six inhabited continents, especially in urban areas. They’re beautiful, they’re low-maintenance, and most of all, they’re tough. How tough are ginkgoes? Well, they’re one of the few living things to survive the atomic bomb blast in Nagasaki, Japan in 1945. Several large ginkgoes were well inside the blast range, got completely scorched, and were presumed dead. But the following year, they sprouted leaves and kept on truckin’. These trees are still alive today and appear none the worse for wear. But if you think about it, the A-Bomb at Nagasaki was a firecracker compared to the asteroid impact that wiped out the dinosaurs 65 million years ago, and plunged the whole planet into a nuclear winter of darkness and cold. Ginkgoes survived that, too. So if they can survive a thermonuclear blast and a global mass extinction event, common urban problems such as smog, compacted soil, and high levels of electromagnetic interference are no big deal.
As such, they’re really, really common in urban and suburban areas. City streets, parks, subdivisions, malls, and other heavily humanized areas where other trees have a hard time surviving are all great places to find ginkgoes. However, they can be found semi-naturalized as well. I was exploring an old abandoned home site several years ago that had two large ginkgoes planted in the overgrown yard, male and female. And lo and behold, there were baby ginkgoes growing in the brushy woods all around. So although this isn’t a tree you’ll find in deep, unspoiled wilderness, it’s reasonably common in civilization, from its heart to its fringe. And for those of y’all who are excited by post-apocalyptic fantasies of fighting it out in the urban wild in a dystopian future, you’ll want to keep this tree in mind.
Why? Well, it’s a great wild edible. Those same putrid fruits hold a great treasure inside of them. When collected and fleshed out (I highly recommend rubber gloves for this), the seeds contained within are both nutritious and delicious. They can be eaten raw, although they’re better cooked. Roasting is the way to go in my experience – they have a rich, nutty, buttery flavor that’s a lot like pine nuts. In China and Japan, ginkgo nuts have been considered a delicacy for thousands of years, and are used in all manner of dishes, from entrees to desserts. They’re good for you, too. Ginkgo nuts are high in protein, fat and carbohydrates, and are also rich in potassium, magnesium, vitamin B6, and vitamin C. One ounce (a small handful of them) is 52 calories, .5 grams of fat, 11 grams of carbs, and 1.2 grams of protein. Not bad.
While ginkgo nuts aren’t something to look for in a wilderness survival situation, if you’re living on the fringe of society in an urban area, or are facing a catastrophic grid-down scenario in the city, they’re worth knowing. They’re also great if you just want to do some urban foraging and try something new as an exotic snack. While most planted ginkgoes are fruitless males, since they are less messy and don’t smell as bad, some city planners and landscapers go the opposite route and plant female trees instead. The motile spores released by the male trees are worse for allergy sufferers than any pollen ever could be. A word of caution – don’t eat the fleshy fruit covering the seed, or too many raw seeds. They contain a chain of chemicals that can make you sick, causing vomiting and even seizures. And as we’ve said many times here before, only eat a little bit of any wild plant to see how your body reacts before you dive in with both feet. But if you eat only the seeds and make sure to cook them, all should be good.
However, ginkgo’s real claim to fame is medicinal. Used in Asian medicine for thousands of years, ginkgo biloba tea or extract caught on as a popular nutritional supplement in the West in the second half of the twentieth century. It makes some bold claims. Ginkgo enthusiasts swear by it for helping improve circulation, relieve menstrual cramps, and even treat mental disorders such as Alzheimer’s, dementia, and schizophrenia. There’s not a huge body of research to back these claims, but what exists is promising. A study done by Schwabe Pharmaceuticals years ago showed that taking an extract of ginkgo leaf called EGb 761 for at least six months proved to be as effective as the prescription drug donepezil, or Aricept. Ginkgo is known to stop or at least slow down the memory loss associated with Alzheimer’s. Many people who suffer from normal, non-Alzheimer’s age-related memory loss absolutely swear by it for helping restore memory and sharpen mental function. Those afflicted with schizophrenia also may benefit from taking ginkgo extract in addition to their prescription antipsychotics. In traditional Chinese medicine, it was used as an anti-inflammatory to relieve headaches, menstrual cramps, and muscle pain. It was also used externally as a poultice to help treat sores, cuts, bruises, and scrapes. Traditionally, and for our purposes, the best way to prepare ginkgo is a hot infusion (tea) of the leaves. It’s even better with honey. While the American FDA doesn’t recognize ginkgo biloba as having any valid medicinal uses, other modern, western countries beg to differ. Ginkgo has been an accepted treatment for age-related memory loss by the German National Pharmacopeia since the 1960s. Since the FDA doesn’t have the best track record of taking plant-based remedies seriously (as we learned last week, with its smear campaign against sassafras), I’m inclined to lend credence to ginkgo’s claims.
Ginkgo is an example of how we can find food and medicine in the natural world anywhere we look, even if that’s down an urban street. The ginkgo tree that I forage nuts from is in front of a courthouse in a heavily traveled downtown area. While it’s not a tree most of us would need to depend on for true survival (until the apocalypse comes, anyway), ginkgo is still worth knowing as an alternative food source, and as a valuable medicine. And if that dark day ever does come where we have to fight our way through the urban jungle while foraging for ginkgo nuts and hunting squirrels and pigeons in city parks just to stay alive… well, the ginkgo trees will be there. They did outlast the dinosaurs, after all.
What about you? Have you ever tried ginkgo nuts? Do you take the extract and swear by it? Tell us in the comments!