Ginkgo Biloba is a deciduous, flowering tree that is native to China. Historically, it has enjoyed a very special status in Chinese and Japanese temple gardens. However, nowadays, it is commonly found in Western streets, as it does not shy away from urban areas. It is fungus and insect resistant and this has been a reason for its popularity as an ornamental tree
Ginkgo Biloba is a seed-bearing, flowerless plant and belongs to the division Gingkophyta, a group of plants that are of particular interest to paleobotanists (botanists specializing in the study of fossils). Two of the genera of gnetophytes are now extinct, and the third, Gingko, has only one member alive today, Ginkgo Biloba
Ginkgo Biloba is probably the oldest seed-bearing plant and it is highly valued for this reason. Ginkgo Biloba is also called the maidenhair tree because its leaves are bilobed and resemble those of the maidenhair fern. It is often called a living fossil, because once it was unclear whether it was present in the wild or not.
Fossil leaves have been found in regions as far apart as Australia, Mongolia, Alaska, England, and Eastern Europe that resemble the leaves of “Ginkgo Biloba”. These leaves are attributed to a species of the now-extinct genus Gingkoite. However, there are similar variations found in the leaves that are not uncommon to see in the leaves of two Gingko Biloba trees nowadays. So it has been suggested to abandon the Gingkoites genus and the placement of these leaves in the genus Gingko.
There is another form of gingkophyte leaf that is found in fossils. It has four lobes and belongs to the genus Baiera.\
Ginkgo Biloba also lacks the stalk. It has decreased progressively in its distribution around the world, and there are speculations that Southern China may be the last natural home of “Gingko Biloba”.
The seeds obtained after removing the fleshy outer covering have had medicinal use in China for more than 3000 years. They are used to treat asthma and improve cardiac function. Ginkgo Biloba leaves are also considered to be medicinally important for their memory enhancement effects, there are hopes that a treatment or prevention for Alzheimer’s and dementia could be soon discovered.
Form and Function
The tree reaches a height of 20 to 30 meters. In a young tree, there is the main trunk which shows regular branching. In an older tree, however, the branching is much more irregular and asymmetrical.
There is a spectacular feature of Gingko Biloba branching. There are long branches that bear leaves in the spring season. There are short branches that bear no leaves. However, in subsequent years, short branches also grow leaves in clusters.
A short branch sometimes starts growing and becomes a long branch. On the other hand, a long branch may shorten its ends and give rise to a short branch. The tree is deciduous and falls Ginkgo Biloba leaves in the autumn, which is golden-brown in color at the time. The color may vary in some cultivars, however.
The trunk and long shoots produce annual growth rings each year, due to the conspicuous activity of vascular cambium, which continues to add secondary phloem and secondary xylem each year and is responsible for the lateral growth. Short shoots do not show much lateral growth, and only softwood develops. When you cut a long shoot or the trunk, the impermeable heartwood is visible.
The leaf is usually bilobed, dichotomously veined, and fan-shaped, much like maple and maidenhair fern leaf. However, these features are not consistent and there may be slight variations. The leaves on short branches are truly bilobed, but, the long branches leaves are divided into two lobes through a sinus, and each lobe may be further lobed. Multilobed leaves are also found on new branches.
The dichotomous venation is characteristic of Gingko Biloba and is also found in the extinct species of its sister genera. However, the venation pattern is the open one and the veins do not unite later. There may be some irregularities nonetheless.
Ginkgo Biloba takes almost 14 months to complete its reproductive cycle. It is also dioecious, meaning that the male and female reproductive organs are found on separate trees.
The gametes form on separate trees, and the male gametophyte or pollen grains are carried by wind to the ovule of the female tree, which is a female gametophyte. After pollination, fertilization occurs and the ovule changes into a seed.
After fertilization, the embryo feeds on the nutritive female gametophyte and grows. A mature seed consists of a dicotyledonous embryo, a female gametophyte nutritive tissue, and a seed coat that has an inner hard covering and an outer fleshy wall.
Since Ginkgo Biloba is a very old tree, its medicinal literature is as old as 4000 years. Ginkgo Biloba tree itself is as old as 200 million years and is thought to be one of the oldest trees present on the face of the earth.
Ginkgo Biloba leaves have gained high value for they are thought to be helpful in problems, related to memory, vision, and anxiety. But, on the other hand, there is a lack of true scientific research to back these claims.
The tree is often called a “living fossil”, and it can survive for as long as one thousand years. The literature, as old as 2600 BC, describes its use as a cure for asthma and bronchitis.
Gingko leaf extract is used in cosmetics. In China and Japan, its seeds are fried, cooked, and served after removing the pulp.
How Does It Work?
Gingko contains antioxidants that may provide aid in Alzheimer’s disease. It improves blood circulation which might, in turn, improve the function of the brain, eyes, ears, etc.
Gingko seeds contain a toxin that kills bacteria and fungi. Some other toxins contained in it may cause seizures, loss of consciousness, and many other potential side effects in humans.
Some research shows that Gingko products may act as anti-aging agents. Ginkgo Biloba is consistent with the findings that the default condition in plants, especially Gingko Biloba, is immortality. Ginkgo Biloba usually does not die due to aging, a phenomenon that seems to be very odd to us humans, and can only be killed by some foreign agency, or an accident.