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Why are ginkgo trees called living fossils?
Because ginkgo tree is the oldest tree species in the world, it existed as early as 200 million years ago.

Later, about 2 million years ago, there were many glacial movements on the earth. Many plants are buried in glaciers, and most ginkgo trees are extinct. Only some ginkgo trees in China have survived and become rare treasures like giant pandas.

Ginkgo tree retains the original characteristics of many plants, and the leaves on both sides are almost the same, which is extremely rare in many purified plants. In addition, scientists can study the ancient state of the earth through ginkgo biloba, so it is called a living fossil in plants.

The characteristics of ginkgo tree:

Ginkgo biloba (scientific name: Ginkgo biloba)

Length), a deciduous tree of Ginkgo in Ginkgoaceae. Ginkgo biloba is a deciduous tree with a DBH of 4 meters. The bark of young trees is nearly smooth, light gray, and the bark of big trees is grayish brown, irregular and rough longitudinally. There are long branches and slow-growing short branches.

The crowns of young and mature trees are conical, while the crowns of old trees are roughly oval. Branches are nearly whorled and extend obliquely upward (large branches of female plants are often more developed than those of male plants). Leaves alternate, scattered radially on long branches, petiole slender, fan-shaped, light green on both sides, glabrous. Scattered on long branches and clustered on short branches. Its pulse type is "bifurcation pulse".

Usually 2-lobed on long branches, base broadly cuneate. Cones are dioecious, unisexual and clustered in the axils of scaly leaves at the top of short branches. It blooms in April and matures in June, 5438+ 10. Seeds have long stems, drooping, often oval, obovate, ovoid or nearly spherical. The seed coat is fleshy, covered with white powder, and the exocarp is fleshy, yellow or orange when mature.

The fruit of ginkgo tree is commonly known as ginkgo, so ginkgo is also known as ginkgo tree. Ginkgo trees grow slowly and have a very long life. Under natural conditions, Ginkgo biloba takes more than 20 years from planting to fruiting, and will bear a large number of fruits after 40 years. So some people call it "gongsunshu", which means "public can eat grandchildren". It is a longevity star in trees, which has ornamental, economic and medicinal values.