What is a tree?
A tree is a tall, woody plant with a single main stem — the trunk — that supports branches and leaves. Trees can live for decades, centuries, or in rare cases thousands of years, growing a new ring of wood each season.
Why trees matter
- They turn carbon dioxide into the oxygen we breathe.
- Their roots hold soil together and prevent erosion.
- They provide homes and food for birds, insects, and mammals.
- Shade from trees cools cities by several degrees.
A few favourites
Oak
Broad, sturdy, and long-lived. A single oak can support hundreds of species.
Giant Sequoia
The largest trees on Earth by volume, some over 80 metres tall.
Silver Birch
Slender with papery white bark; one of the first trees to colonise open ground.
Japanese Maple
Grown for its delicate leaves that blaze red and orange in autumn.
Three quick facts
- The oldest known individual tree, a bristlecone pine, is over 4,800 years old.
- Trees communicate through underground fungal networks sometimes called the "wood wide web".
- There are roughly three trillion trees on Earth — about 400 for every person.