Which of the following is often used in landscaping for shade due to its large canopy?

Ulmus americana, commonly known as the American elm, is frequently used in landscaping for shade because of its expansive and dense canopy. This species is known for its graceful, arching branches that create a broad, umbrella-like shape, making it particularly effective at providing shade. The significant leaf coverage allows it to filter sunlight effectively, contributing to cooler areas beneath the tree, which is desirable in both residential and public landscaping.

In addition, the American elm is valued for its adaptability to various soil types and conditions, its resistance to some urban stresses, and its historical significance in American landscapes. While its appeal is sometimes diminished due to susceptibility to diseases like Dutch elm disease, successful cultivation practices and resistant cultivars have helped maintain its use in landscaping projects focused on shade provision.

The other options, while they may also provide some level of shade, do not match the American elm's broad canopy and extensive leaf coverage. For instance, Quercus rubra (red oak) and Tsuga canadensis (eastern hemlock) are valued for their own unique characteristics but typically do not have the same kind of expansive canopy that makes Ulmus americana a preferred choice for shade in urban settings. Pinus echinata (shortleaf pine), on the other hand