In USA, the Autumn season commonly referred to as Fall, starts on 21st of September, each year bringing an end to summer and its heavy schedule of vacation. Temperatures normally remain in the mid 50s and 60s(Fahrenheit) in most places.Fall Color:
Fall is the season during which leaves change colors from green to yellow, then to orange and then to red before they started to fall and hit the ground. September and October are the best season to view these spectacular display of fall colors in US.Why do leaves change color during Fall?
During summer the daylight is long and plants continue to prepare their food through a process known as 'Photosynthesis' by converting water absorbed from their roots and carbon dioxide from the air. This process is done with the help of sunlight and a chemical called chlorophyll which is responsible for the green color in plants and leaves.
As summer ends and fall begins, the daylight becomes less and less available to plants making its very difficult for them to prepare food. So, plants stop their photosynthesis and hence chlorophyll slowly starts to disappear and thereby changing the color of the leaves from green to yellow-orange.
As winter starts, these leaves completely shut down their food factory and the plants start to live off the food stored during earlier seasons and take rest during winter. Most trees like maple, oak shed their leaves completely during winter making them hard to believe that they are alive and as spring starts, trees are again filled with green leaves as if they have come from fresh roots.
Where to go?
Since weather is pleasant in most places, it won't stop you from continuing your touring and vacation. If you are a nature lover like me, spring and fall are the best seasons to tour around USA. You will be surprised to see the land and hills filled with trees full of bright yellow - orange colored leaves during this season.