Mission and history

The mission of The Morton Arboretum is to collect and study trees, shrubs, and other plants from around the world, to display them across naturally beautiful landscapes for people to study and enjoy, and to learn how to grow them in ways that enhance our environment. Our goal is to encourage the planting and conservation of trees and other plants for a greener, healthier, and more beautiful world.

The Morton Arboretum was founded in 1922 by Joy Morton (1855-1934). The inspiration for the Arboretum had its origins in Mr. Morton’s own family tree. His father, J. Sterling Morton (1832–1902), was the founder of Arbor Day. Over the decades, the Arboretum has continued to evolve, while staying true to the Morton family motto, “Plant Trees.”

Joy Morton

Joy Morton (1855-1934) founded the Morton Salt Company in Chicago in 1885, and later The Morton Arboretum 25 miles west of the city in Lisle in 1922. LEARN MORE

Arbor Day

The founder of The Morton Arboretum, Joy Morton, was the son of J. Sterling Morton, who originated Arbor Day in 1872. “Plant Trees” was the Morton family motto. LEARN MORE

Logo Story

The logo of The Morton Arboretum is symbolic and has meaningful ties to the Morton family emblem. Learn more

Four Columns

Inspiration and intrigue surround the sculptures known as the Four Columns near the Hedge Collection. Learn more

Morton Family Cemetery

Arboretum founder Joy Morton set aside this one-acre parcel as a family burial plot in 1925. It is the final resting place for himself and members of his family. Learn more

Thornhill Education Center

Set on the site of the former Morton family mansion, the Thornhill Education Center provides space for classes, programs, and events. The original Morton family library remains a part of the historic structure, which contains a unique bay of stained glass windows dedicated to the trees through history. Learn more

Administration & Research Center

The Administration & Research Center has evolved to serve the changing needs of Arboretum staff and visitors over several decades. Learn more

Historical Timeline

1872 J. Sterling Morton (1832-1902), father of Arboretum founder Joy Morton (1855-1934), established Arbor Day in Nebraska. (He later served as Secretary of Agriculture under President Grover Cleveland.)

1909 Joy Morton acquired property in Lisle, Illinois, where he built his country estate and named his home Thornhill.

1922 The Morton Arboretum was founded in 1922 by Joy Morton with a focus on living collections, a research library, and a herbarium.

1934 Joy Morton died. His daughter, Jean (Mrs. Joseph M. Cudahy, 1883-1953), became Chairman of the Board of Trustees and served in that capacity for 19 years. Under her leadership, the Arboretum developed a national reputation. In memory of her father, she built the Administration Building, which provided a reception area for visitors, staff offices, and space for the herbarium and library. The Hedge Garden was established, making it the oldest hedge demonstration in a U.S. public garden.

1937 Mrs. Cudahy commissioned a custom-designed open air bus to provide tours of the grounds for visitors; it was inspired by vehicles used at the World's Fair ("A Century of Progress") in Chicago in 1933-1934.

1938 The Ground Cover Garden was planted.

1939 Clarence Godshalk (1897-1988) was named director. He had commenced his employment as superintendent of the grounds in 1921. Trained as a landscape architect in the naturalistic style of O.C. Simonds and others, he further developed the Arboretum’s distinctive landscapes.

1940 Mrs. Cudahy started the Arboretum’s renowned education program by inviting the gifted naturalist and ecologist May Theilgaard Watts (1890-1975) to teach.

1942 Thornhill Building, a new educational facility, opened on the site of the razed Morton mansion. May Watts developed an innovative public education program, the first such program among U.S. arboretums. She was also known for her Tree Finder and Flower Finder identification books, and her book Reading the Landscape (1957, revised 1975 and 1999). In 1963 she originated the Illinois Prairie Path, the first rails-to-trails project in the U.S.

1952 A rustic Outpost with overnight accommodations was completed to house week-long workshops and later a 5th grade residential environmental education program.

1953 Sterling Morton (1885-1961), son of Joy Morton, became Chairman of the Board after his sister Jean’s death, serving for eight years. Achievements during his tenure included adding a new research wing to the Administration building, initiating a practical research program; dedicating an auditorium in the building to Jean; increasing the size of professional staff; and adding considerable acreage.

1957 Construction of the East-West Tollway and widening of Illinois Route 53 changed the Arboretum landscape, resulting in new new lakes, roads, and a staffed gatehouse.

1960 An admission program went into effect.

1961 Suzette Morton Davidson (1911-1996) became Chairman of the Board after her father Sterling’s death, serving for 16 years.

1962 The Schulenberg Prairie restoration project began.

1963 The Sterling Morton Library was built, and Mrs. Davidson greatly expanded the rare botanical book and art collection. A formal scientific Research program was established.

1966 After 45 years at the Arboretum, Clarence Godshalk retired and was succeeded as director by Dr. Marion Trufant Hall (1920– ), a scientist of broad interests and experience. Over the next 24 years he led the Arboretum's growth as a major scientific and cultural institution. An elm-breeding program was started to develop hybrids resistant to Dutch elm disease.

1968 The Plant Clinic opened.

1972 The Arboretum celebrated its 50th anniversary. A general master plan was developed; the Visitor Center was built in memory of Suzette's mother; a membership program was inaugurated; the first catalog of the plant collections was published; and an exhibition of the Arboretum's rare books was held at the Newberry Library in Chicago.

1973 The first stand-alone Visitor Center opened.

1976 The Arboretum was accredited as a museum by the American Association of Museums.

1977 Suzette Morton Davidson retired and selected her successor, Charles C. Haffner III, as the first person outside the Morton family to serve as Chairman of the Board.

1980 The volunteer program was formalized.

1982 The new Research Center was dedicated.

1985 The Fragrance Garden was developed.

1990 Dr. Gerard T. Donnelly, a botanist with background in forest ecology and experience in teaching and garden administration, was hired as Executive Director.

2000 W. Robert Reum became Chairman of the Board.

2004 The Branching Out! strategic initiatives and first-ever capital campaign resulted in new programs, services, and facilities, along with expanded outreach to the public. Projects coming to fruition this year included a visible and welcoming entrance to the Arboretum, an environmentally-sound main parking lot, a new Visitor Center, a Maze Garden, and a restored Meadow Lake.

2005 As part of the Branching Out! site redevelopment, the four-acre Children's Garden opened. The Morton Arboretum co-hosted the American Association of Botanical Gardens and Arboreta annual conference in Chicago and suburbs.

2011 The Morton Arboretum received accreditation as an arboretum through ArbNet.

2012 The Morton Arboretum renewed its accreditation as a museum with the American Alliance of Museums.

2013 The Arboretum introduced a major wintertime exhibition, "Illumination: Tree Lights at The Morton Arboretum."

2014 Darrell B. Jackson became Chairman of the Board.

2015 For the first time, the Arboretum served its 1,000,000th annual visitor.

2017 The Growing Brilliantly campaign was publicly launched to raise support for a new curatorial and operations center, Center for Tree Science, tree conservation programs, new plant development, and Children's Garden enhancements.