The Florham Arboretum is situated on the Fairleigh Dickinson University campus in Madison, NJ. It is the former Florham estate of Florence Vanderbilt Twombly and Hamilton McKown Twombly. Developed in the 1890’s, some notable landscape architects who had a role in its landscape were: Frederick Law Olmsted, the Olmsted brothers, Warren H. Manning, and Brinley and Holbrook. Management of the estate’s landscape and greenhouses was under the direction of Arthur Herrington, noted horticulturalist and plant breeder, who came to Florham from Kew Gardens, England.

The main entrance is flanked to the left by weeping European beech leading to an allée of American linden. Southern Japanese hemlock, western hemlock, Washington English yew, and a grove of Japanese false cypress grace the approach to the Mansion. Adorning the great lawn in front of the Mansion are two large specimens of cedar of Lebanon, a large Nordmann fir, a large weeping Canadian hemlock, and a spectacular linden (Tilia ‘Petiolaris’).  They have a large collection of common boxwood greater than 15 feet in height and width.  To the north west of the Mansion stand oaks that originated prior to the estate development, that were plotted on the 1890 topographic site survey.