Key to Trees of Logan Canyon

Option 1
Are the opposite leaves simple (one blade attached to a stalk or petiole), and the leaves palmately lobed (like fingers on the palm of a hand)? Clue: the fruit is a winged samara in pairs. These are maples.

Simple opposite leaves sketch


Option 2
Are the opposite leaves compound (3 to many blades attached to one leaf stalk)?

Compound opposite leaves sketch