We love our trees. All summer they absorb sunlight, carbon dioxide, and nutrients from the soil and turn them into new green leaves that shade us on hot days, keep moisture in the air and soil, and harbour a huge number of living organisms.
As the days get shorter and cooler, all those leaves will soon become a liability. They can no longer photosynthesize as the temperature drops, but they still lose water, especially when it’s windy. No problem. Deciduous trees in our part of the world have adapted to winter by sending some of the nutrients from their leaves back down into the roots for storage. That’s why they turn colour, by the way – chlorophyll components break down, revealing the previously masked oranges, yellows, and reds of other chemicals.