Yellow leaves reveal pigments that were there all summer. Red leaves are newly made. Why eastern North America often looks redder than Europe.
https://searchable.allabor.net/article/why-do-leaves-turn-red-and-why-more-them-america

Yellow leaves reveal pigments that were there all summer. Red leaves are newly made. Why eastern North America often looks redder than Europe.
https://searchable.allabor.net/article/why-do-leaves-turn-red-and-why-more-them-america