Difference Between Sycamore And London Plane Tree

(Image credit: phbcz)

The London plane tree (Platanus × acerifolia) is a tall, attractive but messy tree that is native to Europe. Sycamore (Platanus occidentalis) is the American plane tree. They are related species that are difficult to tell apart. 

Meet the American Sycamore

What’s the largest hardwood tree in North America? If you guessed the American sycamore, you are correct. It shoots up to 140 feet (42.6 m.) tall with exfoliating bark, giving the tree a camouflaged look. The outer bark is light brown, and inner is back white, green or yellow. This should help with sycamore tree identification.

Sycamore leaves are quite large, up to 10 inches (25 cm.) across. They have lobes and distinctive veins. Fuzzy on the underside, each leaf has several large teeth as well as a swollen base containing a lateral bud. Female flowers produce the tree’s characteristic fruiting balls.

You won’t find any native American sycamores in Minnesota. But otherwise, the tree grows in every state east of the Great Plains. Look for it in flat lands near streams and rivers. It grows well in loamy soil, but also tolerates wet soil conditions.

Meet the London Plane Tree

Since the sycamore is in the plane tree family, the London plane tree and the sycamore are relatives. In fact, the sycamore is one of the “parents” of the London plane tree, a hybrid resulting in a cross between the sycamore and the oriental plant tree (Platanus orientalis). 

The London plane tree hybrid is thought to have occurred in the 1600s. For centuries this tree has been popular in major European cities and some American cities, including New York and San Francisco. It is difficult to distinguish it from the American sycamore, given its tall trunk and exfoliating bark. 

London Plane Tree vs. Sycamore

Although American sycamore and London plane tree look very similar, this is to be expected given their familial relationship. If it is essential to identify a tree in your yard as one or the other, here are some facts you should use to make your bet. 

  1. If it’s planted in a big city, it will probably turn out to be a London plane tree. These trees are cultivated more than the sycamore because they are thought to be more resistant to Anthracnose.
  2. However, if the tree is growing along a stream or bottomland in the Eastern United States, vote for the sycamore. This is sycamore territory. 
  3. Look at the bark of the trees. Both exfoliate, but the underbark of the London plane tree is largely olive green, while that of the sycamore is a mix of white, cream, green, and gray.
  4. Look at the fruit. The London plane tree bears two per stalk while the sycamore one per stalk. 
Teo Spengler
Writer

Teo Spengler has been gardening for 30 years. She is a docent at the San Francisco Botanical Garden. Her passion is trees, 250 of which she has planted on her land in France.