Are red maples always red in the wild? No, which is why cultivars such as "Red Sunset" maple trees are a better choice for those seeking crimson in the yard.
David Beaulieu
Just because the fall leaves of a tree you encounter aren't red, don't assume it's not a red maple.
The fall foliage of red maple trees (Acer rubrum spp.) unfortunately sometimes makes a liar out of the trees' name. Witness the tree in this photo, the fall color of which is primarily yellow. That's why it's best to stick with cultivars known for their fall color consistency. If you want red fall foliage, I would suggest purchasing Acer rubrum 'Red Sunset,' a tree that will reach about 50' in height, with a spread of a little less than that.