Which tree is known by the common name Sourwood?

Sourwood is commonly referred to as Oxydendrum arboreum. This deciduous tree is native to the eastern United States and is particularly valued for its beautiful, fragrant white flowers that bloom in the summer, as well as its striking foliage that turns vibrant shades of red and orange in the fall. The name "Sourwood" comes from the bitter taste of the tree's leaves and the wood, which has historically been used to make a type of honey by bees that pollinate its flowers.

The other trees listed have different characteristics and belong to different families. Parrotia persica, known as Persian ironwood, is recognized for its striking bark and fall color but is not associated with the sourwood name. Platanus x acerifolia, or London plane tree, is a hybrid known for its urban resilience and distinctive bark, but again, not related to sourwood. Lastly, Pyrus calleryana, known as Callery pear, is recognized for its white spring flowers and often problematic growth patterns, and it too bears no relation to sourwood. Each of these alternatives highlights the diversity of tree species but without the specific traits that define Oxydendrum arboreum.