Western Plane is notable as one of the parents of the hybrid London Plane. It has many common names including Buttonwood, the most widely used being American Sycamore, a confusing name (especially outside America) as it is not closely related to Sycamore. The epithet occidentalis means 'western'. Introduced c.1634.

Native to eastern and southern North America.

Monoecious. Wind-pollinated. Wind- and water-dispersed. Long-lived (500 years).

Tall (30–40m), often with multiple trunks. Leaves large (10–22cm), 3–5 shallow lobes, margins with small teeth at secondary vein tips, densely woolly when young, soon glabrous, bases cordate and decurrent. Seed-balls usually single, on long (10–15cm) peduncles.

Naturally thrives on floodplains with deep fertile soils. It is unlikely to be widely planted in Britain and Ireland until genetic selections better suited to local conditions, especially spring frosts, are available and disease resistance is improved through tree breeding.

In the wild, mature trees are often hollow, harbouring wildlife, including dens for Black Bears (Ursus americanus). No notable associations where introduced.

This species is highly sensitive to plane anthracnose, caused by the ascomycete fungus Apiognomonia veneta.

In its native range, the timber is used for flooring and utility furniture. In ornamental use it has largely been replaced by London Plane.