On June 18, 1936, the Long Island State Park Commission was given 200 acres of the Cutting estate for use as an arboretum by Mrs. Bayard James, daughter of William Cutting, with the stipulation that she and her mother keep full use of the property as long as either is living. Both the house and property were given to the people of Long Island "to provide an oasis of beauty and quiet for the pleasure, rest, and refreshment of those who delight in outdoor beauty; and to bring about a greater appreciation and understanding of the value and importance of informal planting". The Long Island State Park Commission took over control of the park on Dec. 1, 1952. An endowment fund of $1,000,000 had been set up by Mrs. Cutting who died November 15, 1949 Alterations were made to the property including the addition of bathrooms and parking lots and adding a tearoom to the main house. The park officially opened to the public on May 15, 1954. In keeping with the purpose of the gift, the commission decided that there would be no picnicking, bathing, horseback riding or playgrounds allowed on the property. Today, the park has a variety of nature trails including: the Woodland Garden Walk, the Perennial Garden Walk, the River Walk, the New Pinetum Walk, the Old Pinetum Walk, the Holly Walk, the Paradise Island Walk and the Royce Rhododendron Walk. There are recreational programs and a food and a gift shop at Westbrook. The Bayard Cutting Arboretum Horticultural Society, founded in 1974, donates profits of its activities to help support the Westbrook Manor. As part of its fundraising activities, the organization operates Granny's Attic located in the lower carriage house and hosts two plant sales a year. Recent Westbrook Manor projects funded in part by the Horticultural Society include: porch restoration, porch pillars restoration, new carpeting, Tiffany windows restoration and floor sanding. Two hurricanes affected the state park. In 1954,
Hurricane Carol destroyed over 70 trees but much more damage was done when over 1,000 of some of the most mature trees were lost in
Hurricane Gloria in 1985. The Bayard Cutting Arboretum farm was established in 2012. It was the first Community Supported Agriculture (CSA) program in the New York State park system. The farm produces over 150 varieties of vegetables and berries and also grows culinary herbs and flowers. There are 150 hens providing eggs to members of the CSA program. Two gardens have been restored by the noted public park designer
Lynden B. Miller. The park winter hours (November–March) are 10 a.m. to 4 p.m. Summer hours (April–October) are 10 a.m. to 5 p.m. In 2023, construction began on a new, glass-walled visitor center designed by
MBB Architects. The visitor center, which includes a rooftop solar array, opened in 2024 and includes exhibits on trees and ecology. ==See also==