Trees have been evolving and developing ever since the first seaweed evolved to survive outside its watery environment on dry land, perhaps as long ago as 1.2 billion years. Certainly the oldest known fossil of the first trees were the Archaeopteris which first appeared approx. 370 million ago, although not having the ability to have growth rings like true modern Trees, they were more like giants ferns growing to heights as much as 50m.
True modern trees began to appear in the fossil record approx. 299 million years ago with the first ancestors of modern trees although fairly small and not growing beyond 10m. These were the gymnosperms, (Greek for – naked seed) which later evolved to develop into the trees we know today such as Conifers, Ginkgo, Cycads and Gnetales. The Cycads still have that tree-fern appearance which makes them look prehistoric, while the small selection of Gnetales are generally small unobtrusive shrub like woody plants, the Ginkgo Biloba is the only one known of this Family of ancient gymnosperms, while the Conifers have evolved into a worldwide success story with hundreds of species all over the world and in most environments.
The angiosperms or flowering broadleaved trees appeared in the fossil records approx. 270 million years ago. Both Family of trees (Gymnosperms & Angiosperms) have been evolving and diversifying ever since with an estimated 100,000 different species of trees now growing on Earth today.
Trees have become a vital component of life on Earth, tree roots break up rock through mechanical stress as well as producing a range of enzymes to help break down rocks even further as part of the natural weathering process, Trees absorb minerals from the broken rock to grow organic matter that once returned to the ground mixes with the broken rock, the falling Tree matter creates its own soil ecosystem where the rock weathering by an increasing soil flora and fauna can continue. It is believed that Trees have been the major contributor to the making of the world’s soils upon which the majority of plant life depends.
Trees protect soils from being washed and leached away by holding soils together with its multitude and long lasting roots, trees collect minerals through its roots that are out the reach of other plants and by then using this in their growth and releasing to the surface with their demise, trees provide nutrients for other plants to prosper. With plant life comes insect and animal life which all ultimately depend on Trees to continue to create the environment for soils to be created, without healthy soil plant crops cannot be raised to feed the billions of humans that now inhabit the Earth. It is Mankind’s interest to sustain and encourage Trees to grow where ever we can.
Trees create soil
Trees protect the soil from wind, rain and other extreme weather conditions.
Trees are responsible for providing environmental conditions for the soils fauna and flora, nitrogen cycle etc.
Trees provide food for the majority of land based life.
Trees produce oxygen and store carbon gas’s as wood.
Trees provide shade and can affect the climate by soaking up the suns heat and cooling the ground.
Trees can make clouds and cause rain that helps to transfer moisture deep into continent’s where the moist winds cannot reach.
Trees create and maintain water tables and increase the availability of water to land surface based life.
Man uses Trees for:
Amenity in parks, streets and gardens
Trees hold the soil together on hills to prevent flash flooding and landslides.
Trees prevent desertification
Trees provide wind barriers that can protect crop fields.
Trees provide noise quieting solutions for urban areas
Trees provide ‘green lungs’ for city’s
Trees soak up city pollution
Trees provide natural reservoirs of insect predators such as beetles, lacewings, wasps etc. that can be used to provide protection for crops.