American Sycamore vs London Planetree

These species are similar and are easily confused when they occur together, such as in parks in riparian areas where both wild and planted trees are found. Mature trees are easily distinguished by differences in bark and seeds. London Plane is common in landscaping, occasionally escapes cultivation, and is established in the wild in a few areas. American sycamore is common in riparian areas and occasionally used in landscaping.

American Sycamore (Platanus occidentalis)	London Planetree (Platanus ×hispanica)
American Sycamore (Platanus occidentalis) A large native tree of floodplains and riparian areas, with characteristic mottled bark, especially higher up on trunk and upper branches.	London Planetree (Platanus ×hispanica) A planetree of hybrid origin, widely used in urban landscaping. Established in the wild in a few regions in the northeast and California.
American Sycamore (Platanus occidentalis) Mottling on bark starts higher up on mature trees. Base of trunk has thicker, dark brown bark. Photo © , CC BY-SA 4.0.	London Planetree (Platanus ×hispanica) Mottling on bark, exposing the thin inner layers, usually goes the whole way to the base of the trunk, even on mature trees. Photo © S Brian Treelife, Public Domain.
American Sycamore (Platanus occidentalis) Inner layer of mottled bark is whitish. Photo © Reuven Martin, Public Domain.	London Planetree (Platanus ×hispanica) Inner layer of mottled bark is yellowish. Photo © stuartfraser, CC BY 4.0.
American Sycamore (Platanus occidentalis) Only one seedhead on each stalk. Photo © , CC BY-SA 4.0.	London Planetree (Platanus ×hispanica) Seedheads borne in clusters of 2-3 on the same stalk. Photo © Tony Rebelo, CC BY-SA 4.0.
American Sycamore (Platanus occidentalis) Lobes sometimes less pronounced. Center lobe, if well-defined, is often wider than it is long. Photo © Katja Schulz, CC BY 4.0.	London Planetree (Platanus ×hispanica) Lobes more pronounced. Center lobe usually longer than it is wide. Photo © Stephen James McWilliam, CC BY 4.0.

References & External Resources

These short lists show only links helpful for ID. For a complete list of references and resources also covering other aspects of ecology, visit the links section of the full article on each plant, which is the first entry here.