Boulder Notable Tree Tour

White oak (Quercus alba)

Chautauqua Park was established in 1898 and is on the National Register of Historic Places. In 1903, a parks improvement group designed the park landscape and most trees were planted at that time. Chautauqua Park is known for its variety of trees, especially oaks which like the acidic soils found in the park. This particular white oak is the 4th largest of its species in the state and turns a beautiful red to maroon color reliably each fall.

Chestnut oak (Quercus prinus)

This is the largest Chestnut oak in Colorado with a diameter at breast height (size of the trunk) of 36 inches.

Pin oak (Quercus palustris)

Chautauqua Park is known for its variety of oaks due to the acidic soils found there. A Park Improvement Group designed the landscaping for Chautauqua in 1903 and most of the trees were planted at this time although a few pre-date that.

Plains cottonwood (Populus deltoides spp monilifera)

This massive cottonwood adjacent to Old Main is reported to be the oldest tree on the CU campus and the last survivor of 42 seedlings planted in 1878. Old Main was completed on April 18, 1876, a few months before Colorado became a state. In the late 1800’s, Old Main housed not only the first classrooms, but the President’s home, the library, and the janitor’s quarters. Early occupants thought the building would blow down in the “fierce Boulder wind”. 

Yellow buckeye (Aesculus flava)

One of the largest yellow buckeye trees in the state is on the University of Colorado campus near Hale Science. Hale Science was constructed in 1894 and is one of the oldest buildings on campus. Most large trees in that area, including this beautiful yellow buckeye, were most likely planted in the early 1900’s.

Shumard oak (Quercus shumardii)

Largest Shumard oak in Colorado with a diameter at breast height of 48 inches. On July 28, 2021 at 3pm the air temperature in Boulder was 93°F but at the base of the tree the temperature was about 80°F. The temperature reading of a nearby sunny sidewalk was 105°F!

Red maple (Acer rubrum)

This red maple is now the state champion and is located at the Boulder Valley School District Mapleton Childhood Education Center at the east end of historic Mapleton Avenue. The building was built in 1890 and was home of the Mapleton Elementary School. Historic photos indicate that many of the trees around the school were planted in the 1920’s.

Silver maple (Acer saccharinum)

The Boulder Land and Improvement Company planted over 200 silver maple trees in 1890 to make Mapleton Avenue more attractive. A newspaper editorial read, "Trees will take away the barren look, and give an air of thrift and comfort." Mapleton Avenue was designated a historic district in 1982 and the trees were called out as being a defining feature of the neighborhood. Many original silver maples remain but sugar, red, bigtooth and Norway maples have been planted as eventual replacements. People regularly drive Mapleton Avenue in the fall to see the magnificent shades of red, orange and yellow.

Baldcypress (Taxodium distichum)

Baldcypress is an unusual species in Boulder.

Eastern redbud (Cercis canadensis)

One of the state’s largest redbud trees is growing in front of the Decker-Tyler House, one of the oldest landmarked properties in Boulder. Clinton Tyler was a pioneer who arrived in Colorado in 1860. In 1864 he served as Captain of one of the “100 Days Men” units of the 3rd Colorado Calvary. While serving, he was elected to the Territorial Legislature and was later a Regent of the State University. In 1876, he had his house built on a hill overlooking his 83-acre farm in Boulder. The Boulder County News described his property as being, “…on high land, and in the midst of a transplanted grove, and where trees and shrubbery grow as well as on any land in the West.”

Bur oak (Quercus macrocarpa)

The largest bur oak tree in Boulder is growing in front of the Perry White House, a landmarked property built in 1875. The massive bur oak has a trunk diameter of 50 inches and was planted by the original owners of the home.

American sycamore (Platanus occidentalis)

Three of the state’s largest sycamore trees are growing on the Naropa University Campus. The University is on the original site of Lincoln Elementary School which was established in 1903 and historic photos indicate the sycamore trees were planted not long after that. The original school building, carefully preserved by Naropa University during campus expansion, was designated a Boulder historic landmark in 1989.