Jeff Foott / Sugar Maple (Acer saccharum) trees in autumn, Acadia National Park, Maine

Jeff Foott / Sugar Maple (Acer saccharum) trees in autumn, Acadia National Park, Maine

Jeff Foott / Sugar Maple (Acer saccharum) in autumn, Acadia National Park, Maine

Scott Leslie / Sugar Maple (Acer saccharum) trees in autumn, Mount Carleton Provincial Park, New Brunswick, Canada

Scott Leslie / Sugar Maple (Acer saccharum) old-growth grove, Cape Breton Highlands National Park, Nova Scotia, Canada

Duncan Usher / Sugar Maple (Acer saccharum) leaf on snow-covered ground, Germany

Scott Leslie / Sugar Maple (Acer saccharum) seedling growing beneath old-growth Canadian Hemlock (Tsuga canadensis), Nova Scotia, Canada

Matthias Breiter / Sugar Maple (Acer saccharum) seed pods, Spruce Woods Provincial Park, Manitoba, Canada

Scott Leslie / Sugar Maple (Acer saccharum) forest and trail, Cape Breton Highlands National Park, Nova Scotia, Canada

Scott Leslie / Paper Birch (Betula papyrifera) and Sugar Maple (Acer saccharum) saplings, Cape Breton Highlands National Park, Nova Scotia, Canada

Yva Momatiuk & John Eastcott / Sugar Maple (Acer saccharum) grove in autumn, Montgomery Place Historical Park, New York

Yva Momatiuk & John Eastcott / Sugar Maple (Acer saccharum) leaf, close up of groups of cells turning red in autumn, Hudson River Valley, New York