An Arbor Day Look at Tree Trivia

Arbor Day is the last Friday in April. The holiday encourages tree-planting and the care of trees. Here's a handful of quick facts about trees:

WHAT IS A TREE? Trees live for many years, have a main trunk protected by bark, and a crown of leaves.

THERE ARE LOTS OF TREES The US has nearly a third of it's land covered by trees. Trees cover more of the surface of the earth than any other organism.

TREES ARE BIG AND THEY'RE OLD. Trees are the largest (giant sequoias) and among the longest-living organisms (bristlecone pine, 4,600 years old) on Earth

TREES HELP US BREATHE. Trees are major generators of oxygen which we breathe. Oxygen is produced by a gas exchange in which the trees take in carbon dioxide we exhale as waste. A perfect symbiotic relationship

TREES HELP MAINTAIN THE EARTH'S TEMPERATURE. Trees store carbon while alive, giving it off into the atmosphere when they die or are burned. It is why there is concern over deforestation in the Amazon, Africa, and Southeast Asia, and why schoolkids plant trees on Arbor Day to offset the loss.

THE AWESOME MANGROVE TREE. The mangrove tree is a fascinating specimen, thriving in saltwater, extending many above-ground roots into the soil below. They are also credited with being pioneers in naturally expanding the coastal shoreline. A recent study finds that the mangrove tree of coastal forests around the world actually stores 3-4 times more carbon than temperate or tropical rainforests. The mangrove is a tree that can thrive in saltwater, extending many above-ground roots into the soil below the surface, providing havens for fish.

TREES ARE EVERYWHERE. We have countless products derived from the wood from trees, even rayon.

TREES KEEP COMING BACK. Trees are a renewable resource.

NATIVE AMERICANS LOVED TREES. Trees were another natural resource that native people in the Americas relied on for survival. The western red cedar, for example, was made into totem poles, canoes, the bark was woven into blankets, fishing nets, and even fabric.

TREES FIGHT CANCER. A cancer-fighting agent called taxol, produced by the Pacific yew tree, is used to comvat ovarian and other types of cancer.

TREES WITNESS AND MAKE HISTORY. In Nottingham, England, the Trysting Tree is a huge, thousand-year-old tree believed to have been where Robin Hood met with his Merry Men.

STATES SELECT THEIR OWN STATE TREE. The 50 United States all have state trees, but that only amounts to 39 species. As many as four states have adopted the same tree, the sugar maple. They are New York, West Virginia, Wisconsin, and Vermont. The official national tree is simply designated as the oak.

TREES ACT AS A CLEAN-UP CREW. Trees improve water quality by filtering out unwanted nutrients and pesticides. Trees also store carbon

OAK TREE DROP ACORNS. It takes three or four years for an oak tree to store up enough energy and resources for a masting year, when a sizable amount of acorns are produced. Only one in 10,000 acorns will ever become a tree. Many Pacific region Native American tribes relied heavily on acorns which can be dried, leached of their tannins, and ground into flour.

TREES CAN RECOVER FROM DECAPITATION. If healthy, most deciduous (that's the leafy ones that lose their leaves when it turns cold in the fall), will regrow after their stems or trunks are damaged even if cut off at ground level.

TREES IN SPACE. In 2009, as part of a Canadian experiment, the space shuttle Atlantis delivered 24 willow saplings to the International Space station to see how gravity affects the growth of wood.

TREES OF HISTORY. The nonprofit conservation group, American Forests , offers the propagated offspring of trees associated with special events and people. You can get a honeylocust from Gettysburg, a live oak from the Alamo, a red maple from Washington's Mt. Vernon, or even a sycamore from seeds that went to the moon in 1971 aboard the Apollo spacecraft.

KEEP THE TREES GOING. You can contribute, at no cost, to maintaing the world's rainforest by clicking the button daily on The Rainforest Website. Corporate sponsors contribute based on the number of daily visitors. In its first year of operations in 2000, the site purchased 5,650 acres of threatened rainforest for preservation.