Maple or Sycamore? Look at the Bark, Not the Leaf

These two get mixed up constantly, and it is the leaves that do it. A sycamore leaf and a maple leaf are both broad and lobed, and at a glance in a park they read the same.

Almost everything else about the trees is different, so the answer is to stop looking at leaves.

The bark settles it

An American sycamore has the most recognisable bark of any tree in North America. It sheds in irregular plates, leaving a mottled patchwork of cream, olive-green, grey and white, and higher up the trunk the bark becomes almost pure white and smooth.

No maple does this at any age. Sugar maple bark is grey and furrowed into long vertical plates; red maple is smooth and pale grey when young, breaking into shaggy plates when old; Norway maple is grey-brown with fine regular ridges that never peel.

If you can see the upper trunk and it is white and smooth, it is a sycamore. This works year-round and from a distance, which no leaf character does.

The seeds

The paired wing is the single most reliable maple character. Every maple has it, nothing else common does, and they lie under the tree for months.

If you only have a leaf

It is still possible, with three checks.

Break the leaf stalk. A sycamore's is hollow at the base and forms a cap over next year's bud. A maple's is solid.

Feel the underside. Sycamore leaves are fuzzy underneath, especially along the veins. Maple leaves are smooth or nearly so.

Look at the sinuses. The notches between lobes are shallow and broad on a sycamore, and deeper and more angular on a sugar or Norway maple.

Where the confusion comes from

The name. In Britain, "sycamore" means Acer pseudoplatanus, which genuinely is a maple. In North America, "sycamore" means Platanus occidentalis, which is not related to maples at all.

So a British visitor calling a maple a sycamore is using the word correctly for where they learned it. If you are reading an identification guide, check which continent it was written for before trusting it on this pair.

Quick version

Look up. White smooth bark high on the trunk means sycamore, and nothing else does that. If you cannot see the trunk, look on the ground for a round ball on a stalk or a pair of winged keys, and the ground under a tree in autumn usually has one or the other.

Run it through the tree key if the tree is young enough that the bark has not developed its character yet, which is the one case where this becomes genuinely difficult.

London plane, the third possibility

In cities you may be looking at neither. London plane is a hybrid of American sycamore and Oriental plane, and it is one of the most widely planted street trees in the world because it tolerates pollution and hard pruning.

It has the same mottled peeling bark, so the bark test puts you in the right family but not the right species. The seeds separate them: American sycamore drops its balls singly, London plane usually in pairs on one stalk, occasionally threes.

For most purposes the distinction does not matter. If you are identifying a street tree in a city and the bark is patchwork, London plane is the likelier answer by a wide margin.

Why the confusion persists

Both are large, both are common, both are planted in the same places, and both have leaves a child would draw the same way. The difference is that maples are a huge and varied group spread through forests and gardens, while sycamores and planes are a small group concentrated along watercourses and streets.

Habitat is a real clue. A large lobed-leaf tree on a riverbank or a city street is more likely a sycamore or plane; the same tree in a mixed forest on a slope is more likely a maple.