In June 1874, Frederick Law Olmsted (1822-1903) presented a plan for the U.S. Capitol Grounds for a sophisticated landscape that highlighted the building it surrounded. In his submission for the Architect of the Capitol's annual report, Olmsted wrote that, "The ground is in design part of the Capitol, but in all respects subsidiary to the central structure."

The expansion and landscaping of the area that was completed from 1874 to 1892 incorporated park-like edging, low walls, lamps, careful placement of trees and simple shrubs, and a series of curved walkways that afforded attractive views of the Capitol. Olmsted later added the brick Summerhouse to his design to provide visitors with a drinking fountain and a cool place to rest.

There are currently about 890 trees surrounding the immediate Capitol Building on Capitol Square and more than 4,300 trees throughout the entire 274-acre Capitol Grounds. Some of the most majestic and unmistakable trees on campus were planted during the Olmsted period.

1. Pecan (Carya illinionsis)

Pecan (Carya illinionsis) tree on Capitol Grounds.

A tree for all uses, the Pecan tree serves as the nation's most important commercial nut producer while its prized wood is also used for furniture and flooring. Our tree doesn’t produce fully developed pecans as the regional growing season is not long enough, but it is the tallest tree on campus standing at 115 feet.

2. Japanese Pagoda (Styphnolobium japonicum)

Japanese Pagoda (Styphnolobium japonicum)

Also called the Chinese scholar tree, the Japanese Pagoda can be identified by its oval leaflets, gray-brown bark and shiny green twigs. Shown here, this Japanese Pagoda has extensive cabling to provide stability.

3. Ginkgo (Ginkgo biloba)

Ginkgo (Ginkgo biloba)

Known for its fan-shaped leaves that turn from bright green in the summer to bright yellow in the fall, the Ginkgo's earliest leaf fossils date back 270 million years. The Ginkgo drops all of its leaves at the same time leaving a solid yellow carpet under the tree.

4. Pin Oak (Quercus palustris)

Pin Oak (Quercus palustris)

A classic shade tree, the Pin Oak does not have heavy horizontal branches like most oaks, but instead has many slender branches that arch out. In 1913, this Olmsted original was dedicated to Pennsylvania Congressman Marlin E. Olmsted (no relation).

5. Willow Oak (Quercus phellos)

Willow Oak (Quercus phellos)

The Willow Oak is known for its narrow leaves that undergo color shifts throughout the year — light green in the spring, dark green in the summer and yellow bronze-orange, yellow-brown and russet-red in the fall. One of the largest trees on campus, this tree is often photographed with the Capitol Dome in the background or as a backdrop for members of Congress.

To see these trees in person, find their locations and information about other trees on Capitol Grounds, visit


An endlessly fascinating and succinct blog!

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