Ginkgo/Maidenhair Tree

Basic Information

Tree ID:

Family:

Genus and species:

Description:

This tree is considered a "living fossil", meaning it looks very similar to fossils that are millions of years old. Interestingly, it is the only surviving tree in the entire order of ginkgoales: the order, family, genus, and species are all used to describe a single type of tree. Perhaps more interestingly, ginkgo trees are older than the T. Rex.

Surveyors:

Andre Morales

Location

Area:

Cretaceous Garden

Collected Data

Tree shape:

Open

Date of tree entry:

04/17/2014

Height:

3.89 m

Diameter at breast height:

0.08 m

Bark

The bark is smooth and light grey, with some black scarring. As the tree matures, the bark becomes browner and develops ridges.

Twigs & branches

The branches retain their spurs year-round, from which the leaves and flowers later spring. The spurs are regularly spaced and grow in an alternating pattern.

Foilage

The leaves are characteristically fan-shaped, with most leaves partially divided into at least two lobes. The leaves show a rare, dichotomous veination structure, in which veins emerge from the petiole and travel toward the edge of the leaves, often bifurcating close to the end. Several leaves can emerge from the same spur on the branch, and will also grow in clusters from the tips of the branches.

Reproductive Structures

Ginkgos do not reach reproductive age until reaching two-to-four decades of life; at this time, they begin to produce flowers. The trees are dioecious, meaning some trees produce exclusively male flowers while others show only female flowers. From the coloration, it is apparent that ginkgos do not use insects for pollination; instead, like other gymnosperms, pollination is wind-driven.

Fruit

Since ginkgoes are gymnosperms, they do not produce fruit. However, female trees produce small, spherical, flesh-covered seeds with a short stem. The seeds, called gingko nuts begin white and turn yellow when ripe. They also produce a powerful stench of rancid butter or vomit after dropping from the tree, though they are considered a delicacy when fully cooked. The seeds contain a compound called ginkgotoxin that can cause seizures if not prepared properly.

Seasons

Stunning foliage of a late-fall ginkgo
Winter
Summer

Research

Natural range of distribution:

Habitat:

Due to their incredibly long history (ginkgoes are hundreds of millions of years old, and fossils have been found from the Middle Jurassic Period), they have seen considerable changes in habitat. They were once widespread, but about two million years ago their habitat shrunk and current ginkgoes trace their ancestry back to China. They were preserved in temples in China and Japan (there is some debate as to whether any of the present-day wild trees are not descendants from these temples), but currently enjoy worldwide distribution due to their hardiness and medicinal uses.

Origin, history, and uses:

As stated before, ginkgoes existed during the Middle Jurassic Period, meaning they predated the Torosaurus that has a statue in the Cretaceous Garden, the Tyrannosaurus Rex, and the Triceratops. They were a very successful group of plants for millions of years, but experienced a significant shrinking of habitat about two million years ago. Ginkgoes are thought to be alive today because of their involvement in the lore of the Far East; Confucius was said to have done his teaching under the shade of a ginkgo tree. For this reason, ginkgoes were preserved in temples throughout China, and gradually reintroduced as it gained recognition for its medicinal properties.

Ginkgo products were used for centuries in Chinese traditional medicine. Today, compounds from the tree are also used in commercial medicines for cognitive complaints such as Alzheimer’s. For this reason, ginkgo trees once again enjoy a worldwide distribution.

Phenology:

Ginkgoes are very hardy trees, which allows them to have a wide habitat range. For this reason, ginkgo trees can have widely varying phenology; trees in China can have vegetative growing seasons ranging from 170 days to 260 days depending on their latitude. If winters are mild, trees can begin pollination as early as mid-March, while long winters can make the trees pollinate as late as the beginning of May. Fertilization occurs about 130 days after pollination, meaning a range of August through October. Fertilized ovules mature in the fall, and turn yellow along with the leaves. They eventually drop when temperatures near freezing, which is again climate-dependent. Finally, germination depends on outside temperature, with seeds in warm greenhouses beginning to sprout as early as 6 weeks after falling while seeds outside in cold climates, such as Boston, may take over a year to begin the germination process.

References:

http://www.kew.org/science-conservation/plants-fungi/ginkgo-biloba

http://en.wikipedia.org/wiki/Gingko_biloba

http://oregonstate.edu/dept/

http://kwanten.home.xs4all.nl/

http://www.nature.com/hdy/journal/v94/n4/full/6800616a.html

http://www.commons.wikimedia.org

http://www.bioone.org/doi/pdf/10.1663/0006-8101(2007)73%5B267%3ATPOSRI%5D2.0.CO%3B2