The rustle as you stroll through a carpet of fallen leaves, it must be... Wait a minute. Spring?
Yes. My block has Camphor trees. They are deciduous, but rather wierdly so. They stay green all winter, and then in the spring they shed all of their leaves and put on new ones all at the same time. They look like they are dying in the process, because the new leaves look really sickly at first and they come in as the old leaves are just starting to turn color.