Christmas trees and the science behind them

Dixie Sandborn<dixie@msu.edu>, Michigan State University Extension - November 29, 2016

Fun facts about the science of conifers, a symbol of the Christmas holiday.

It’s beginning to look a lot like Christmas. Fresh Christmas trees are just about on every street corner, or waiting to be cut from your local “you cut” tree farm, taken home and dressed in holiday sparkle. I started to think about Christmas trees, the history, science and traditions associated with this magical symbol of the Christmas holiday. There are pros and cons to fresh or artificial Christmas trees, but as a plant science educator, I will stick to the real deal. In this short series of articles, I am going to share some of what I have learned about Christmas trees, including the science, history, fun facts and the people who grow them here in Michigan.

In my search for a few fun facts, I came across the National Christmas Tree Association website, which is very educational and filled with incredible information. The trees we use to decorate as a symbol of Christmas belong to a group of trees called conifers. Here are some quick facts about conifers:

Conifer comes from the Latin words conus (cone) and ferre (to bare). The word literally means cone bearing.
The reproductive parts of coniferous plants are contained in cones.
Most conifers bear male and female cones on the same plant. All are wind-pollinated.
Most cones are woody, but some, such as those on yew trees, are soft and look like berries.
The cones of pine and spruce trees usually fall to the ground in one piece, but the cones of cedars and most fir trees break up while still on the tree.
There are over 550 species of conifers.
Their leaves are often needle-shaped.
The needles often have a waxy-like surface that keeps them from losing water in dry environments, and freezing.
Since most conifers are evergreens, they can carry on photosynthesis on sunny, winter days when most broad-leafed trees are leafless.
Most conifers do not have to expend extra energy every year to produce a new crop of leaves in spring.
There are seven separate families of conifers. The largest is the Pinaceae or pine family, which includes 232 species.
Botanically speaking, all conifer family names end in “ceae.”
The pine family includes familiar trees such as pine, spruce, fir and larch. Many of these trees make very nice Christmas trees.
The pine family includes the oldest known trees, the bristlecone pines, many of which are known to be more than 4,000 years old.
Conifers are one of the oldest groups of plants, with araucaria-like trees first appearing about 290 million years ago.
Conifers, and other types of gymnosperms, are generally regarded as being more evolutionarily primitive than angiosperms.
The term "gymnosperm" comes from the Greek word meaning “naked seeds.”
Their naked condition is in contrast to the seeds and ovules of flowering plants (angiosperms), which are enclosed within an ovary.

With anticipation of celebrating this Christmas season, you will have a few fun facts to share about Christmas trees. Check the Michigan State University Extension website for upcoming articles about Christmas trees and the science behind them.

For more information on Christmas trees from MSU Extension, check out the following articles: