¿Why are trees so important? If we all plant some 10,0000 trees each we can prevent climate catastrophe, regenerate lost soils, increase biodiversity and preserve vital ecosystems & cycles. Trees are the biggest and oldest living beings on Earth. But around 75% of the ancient forest are vanished for human action. So it's urgent for us to know and understand trees, how to plant them, how to care for them,how to return them to their most important place in nature.In this class we will learn about tree biology and tree functions as well as their influence in our culture.

2. Wangari Maathai "Until you have dug a hole, planted a tree, you water it & you make it survive, you haven't done anything. You're only talking" It's the little things citizens do. That's what will make the difference. My little thing is planting trees.

5. There are more than 80.000 species of trees worldwide. From tiny arctic willows to giant redwoods Trees are the tallest free-standing organisms in the world. They live longer and become larger than any other living organism on earth

6. trees are an example of ‘convergent evolution’; this is when one or more unrelated livings things adopt the same biological traits to solve similar problems In this case a single woody stem to achieve height in order to get enough light.

7. How to distinguish one tree from another? Size and Shape Trunk pattern, texture and colour Leaf shape, size and colour Winter twigs and buds Flowers, fruit or cones Perennial or deciduous Broad leaf or coniferous Angiosperms and Gymnosperms

8. How trees grow? Extension growth: At the tips of each bud and root there are cells called meristem that actively divide themselves Secondary growth: The cambium cells produce the radial growth of the tree, On the outer side of the cambium new cells are added to the phloem. On the inner side of the cambium new woody cells are added to the xylem.

9. Tree structure transports sugary sap made during photosynthesis from the leaves to all the other parts of the tree. Sapwood transports water (by capillarity) from the roots to the leaves Heartwood or woody parts of the Xylem give structure to the tree. Bark protects the tree from the weather, pests, infections,...

10. Bark Cambium Phloem Xylem If we look closer we discover a very complex organism

11. Mycorrhizal roots contain fungal tissue and have an altered structure. Instead of bark root have epidermis and root hairs and act as gatekeepers for the trees, controlling which substances get into the tree

12. The tree get most of the Energy from the photosyntesis on the leaves

14. Food

15. Microclimate Trees cool the earth and the air and regulate humidity For example in the city: -Properly placed trees can reduce heating and cooling costs by 10-20% on average within 10-15 years after planting. -Trees reduce surface asphalt temperatures by up to 36° F and vehicle cabin temperatures by 47° F.

16. Edge/Biodiversity Tree hedgerows act as a wildlife corridor and are hosts of a great biodiversity

17. Soil Protection and Regeneration Trees protect soil from erosion and create it inch by inch

18. Energy and materials

19. Beauty...

20. On the dry Island of Hierro in the Canary Islands, there is a legend of the rain tree; a giant “Til” tree. “ the leaves of wich condensed the mountain mists and caused water to drip into two large cisterns which where placed beneath. The tree was destroyed in a storm in 1612 A.D. But the site is known, and the remnants of the cistern preserved...(This one tree) distilled sufficient water from the sea mists to meet the needs of all the inhabitants” David Bramwell