The London Plane

November 2022 in Seattle, Washington - 071

The London Plane (Platanus × acerifolia, also known as Platanus × hispanica) is a large deciduous tree widely known for its resilience to urban pollution and its distinctive, peeling bark. It is a hybrid of two species, the American sycamore (Platanus occidentalis) and the Oriental plane (Platanus orientalis), combining the best traits of both parents to thrive in city environments.

Description

The London Plane typically reaches heights of 20–30 meters (65–100 feet), with a broad crown of foliage that provides ample shade. Its leaves are large, lobed, and resemble those of a maple tree, contributing to its scientific name acerifolia, which means "maple-leaved". One of the most striking features of the London Plane is its bark, which exfoliates in large patches to reveal a mosaic of green, white, and grey underneath, helping the tree to shed pollutants.

Cultivation and Uses

Widely planted as a street tree in cities around the world, the London Plane is valued not only for its aesthetic appeal but also for its ability to withstand harsh urban conditions, including air pollution and compacted soils. It is also resistant to the plane tree anthracnose, a disease caused by the fungus Apiognomonia veneta, which can devastate other species of plane trees.

In addition to its use in urban landscaping, the London Plane is also planted in parks and large gardens for its shade and ornamental value. Its wood is hard and dense, making it suitable for furniture, flooring, and veneer production, though it is not commonly used for these purposes today.

History

The origin of the London Plane is somewhat unclear, but it is believed to have first appeared in London in the 17th century, possibly arising from a hybridization event in the garden of John Tradescant the Younger, a noted botanist and gardener. Its ability to thrive in the polluted air of London, especially during the Industrial Revolution, led to its widespread planting in the 18th and 19th centuries.

Environmental Impact

The London Plane plays a significant role in urban environments by improving air quality, providing shade, and supporting wildlife. Its large leaves are efficient at capturing airborne particles, and its bark's shedding mechanism helps to remove pollutants from its surface. Additionally, the tree offers habitat and food for various bird species and insects.

Conservation

While the London Plane is not currently considered endangered, its genetic diversity is limited due to its hybrid nature and the widespread use of a few cultivars. Efforts to conserve the London Plane focus on maintaining its health in urban areas, combating pests and diseases, and ensuring the diversity of planted specimens to prevent the loss of genetic variation.

See Also

• Tree
• Urban forestry
• Air pollution