Tree Facts

General Information

Trees help our soil remain healthy by reducing soil erosion and by creating a soil climate suitable for microorganism to grow.

There are over 23,000 different kinds of trees in the world.

A healthy tree can increase your property value by as much as 27 percent while trees with dead branches, hollow cavities and other problems can decrease your property value.

Evergreen trees are green year round because they do not lose all of their leaves in one season. Most will however lose some of their oldest leaves just before they produce new leaves in the spring. Some will lose part of their leaves in the fall.

A tree can absorb as much as 48 pounds of carbon dioxide per year and can sequester 1 ton of carbon dioxide by the time it reaches 40 years old.

Tree leaves are composed of many colored pigments — green chlorophyll hides them during the spring and summer growing seasons. Shorter days and cool temperatures in the fall cause the chlorophyll to break down and the other pigments to be see.

Every state has an official State Tree. We do not have a national tree, however, there is a campaign to have the oak adopted as our National Tree.

Arbor Day, a day site aside to plant and recognize the importance of trees, is not a national holiday. If fact the day observed varies from state to state.

Tree wood is a highly organized arrangement of living, dying, and dead cells.

The beginning and growth of tall woody trees in forests may have played a key role in the extinction of the dinosaurs.

Hundreds of food products (fruit, coffee, nuts, etc.) and food additives (for ice cream, chewing gum, etc.) come from trees.

One large tree can lift up to 100 gallons of water out of the ground and discharge it into the air in a day.

One large tree can provide a day’s supply of oxygen for up to four people.

Each year, one person uses wood and paper products equivalent to a 100 foot tree 18 inches in diameter.

Over 5,000 products are made from trees.

Trees are included in most religions. Some hold certain trees sacred; other use trees to help teach beliefs. The story goes that Buddha received his enlightment under the wisdom tree.

Each year over 600,000 people travel to Macon, Georgia to see 240,000 cherry trees in bloom. The estimated revenue is over $6.5 million dollars per year.


Trees are the largest living organism on earth:

  • Some coastal redwoods are over 360 feet tall
  •  Some swamp ash trees are almost 300 feet tall
  • Giant seguoia trees can weigh over 2000 tons (4 million pounds)
  • It can take 10 minutes to walk around the crown of a giant banyon tree in Calcutta.
  • Monkey trees can have a crown of almost 200 feet.

Trees are some of the oldest living organism on earth:

  • live oaks can live to be over 500 years
  • many giant sequoia trees are 2,500 years old
  • some bristlecone pines are thought to be over 5000 years old.

Trees grown in city conditions often do not live as long (average 13 years less) as trees grown in their natural wooded environment.


Trees trap more of the sun’s energy than any other group of organisms on earth — they are in essence big batteries — the largest on earth. Only 0.1% of the sun’s energy is trapped by organisms — trees account for 50% of all energy trapped by organism.

Almost 98% (by weight) of a tree is made up of six elements: carbon, hydrogen, oxygen, nitrogen, phosphorus and sulfur.

Tree growth occurs in specialized tissues referred to as meristems. This tissue is found at the tips of leaves and shoots. Growth in diameter occurs at the vascular cambium inside the stem.

If a birdhouse is hung on a tree branch, it does not move up the tree as the tree grows.

Trees need food to grow but you can’t buy food for them. They make their own food from sunlight, water, carbon dioxide and nutrients from the soil.

Trees do not grow beyond their ability to support themselves. During periods of stress they shed leaves, flowers, fruit and/or branches.

Trees do not restore and repair wood that is injured and infected — instead they compartmentalize off the damaged tissue. New cells are not produced to replace the damaged cells.

A hollow in a tree is never greater than the diameter of the tree at the time it was injured. It should not spread into the new growth that occurs after the tree was injured.

A tree branch is not actually attached to the rest of the tree. It is held in place by a series of interlocking “collars”. Collars overlap and mesh to form a tight woven pattern of tissue.

During periods of increased or decreased temperature, cracks may develop in the tree trunk — referred to as frost cracks and sun cracks. Both can lead to decay.

Each year trees produce an increment of new growth that covers growth from the previous year.

The age of a tree can be determined by the number of growth rings. The size of the growth ring is determined in part by environmental conditions – temperature, water availability.

Tree trunk cells produced in the spring are larger, have thinner walls and are lighter in color than cells produced in the summer.

Bark is the protective covering of a tree. The outer bark is composed of dead cells. The bark will often split as the trunk diameter increases.

Different parts of the tree grow at different times of the year. A typical pattern is for most of the foliage growth to occur in the spring, followed by trunk growth in the summer and root growth in the fall and winter. Not all trees follow the same pattern.


Most trees do not have a tap root.

Tree roots do not grow very deep. Most tree roots are in the top 12 inches of soil.

Tree roots often extend two to three times the width of the tree.

Roots do not have green chlorophyll.

Roots store more starch than the trunk.

Roots do not have a central pith (soft central tissue) while the trunk does.

The majority of tree roots are non-woody. These root hairs grow within days of when water, temperature, and nutrients are available to promote growth. These non-woody roots only live for a few weeks.

Non-woody tree roots can grow almost any time the soil is not frozen.

Flowers, Seeds

Almost all trees produce flowers — some are very showy. Trees that depend on the wind for pollination have non-showy flowers. Often their flowers are muted shades of green or yellowish green.

Trees can be classified as gymnosperms or angiosperms. Gymnosperms produce their seeds on the surface or tips of an appendage such as a pine cone. Angiosperms produce their seeds inside a fruit such as an acorn.

Most trees are grown from seeds — this leads to variability in the age at which they flower, the amount of flowers produced and the intensity of fall color. Ideally, trees you plant would be grown from seeds collected in a similar climate. Seeds collected in areas with significantly different temperatures will have a different cold and heat tolerance.

Most tree seeds require two growing seasons to germinate. Some tree species require a period of cold weather and others will not germinate for several years.

Cultural Practices

Topping trees is a costly, money-wasting mistreatment of trees.

Tree wound paints and dressings do not help the tree — some actually speed decay.

There is no conclusive evidence that tree wraps help prevent heat or cold injury.

Inserting screws, nails or injecting fertilizer into a tree trunk can cause decay and death.

A newly transplanted small tree will often out grow a larger newly transplanted tree.

Filling a tree cavity is not a very useful practice. If done incorrectly it can lead to further decay.

Non-staked transplanted trees are usually stronger than trees that have been staked.

When pruning, do not leave stubs or cut flush with the trunk. Both can prevent the tree from healing naturally and can increase decay.

Callus and woundwood forms around tree cuts. Neither indicate the tree’s ability to protect itself against decay. The decay must be compartmentalized off inside the tree.

The best time to fertilize a tree is late fall. The next best time is very early spring.

Newly transplanted trees should not be fertilized for a year.

Winter hardiness decreases for several weeks after pruning —- do not prune in late fall or during severe cold weather.

The best time to transplant most trees is in the fall. There are some exceptions.