The Osborn campus encompasses 56 acres on the highest point in Rye, New York. There are 1,000 trees on campus, representing 116 different species, some of which date back to The Osborn’s founding in the early 1900’s. The Co-Founder, John Sterling, envisioned a landscape plan that was modeled on the “pleasure grounds” of England; it features a winding carriage drive, open lawns and shaded walks. Sterling’s intention was to plant at least one tree of each variety suitable for the climate. In all, 2,258 trees were planted under his watch, some from seeds brought by European laborers. Special care was devoted to planting “specimen” trees of exceptional beauty, many remain to the delight of those who visit the campus in every season.

A total of 116 species are listed in its inventory. No individual species makes up more than 10% of the population at the property. Norway spruce are the most common with 82 trees (8% of the population). There are 62 Norway maple and 57 white pine trees on the property. When looking at the genus composition, there are none that meet or exceed the 20% ideal threshold. The most common genus is maple (Acer) with 173 trees (17% of the population). No family exceeds 30% of the population; the most common in Pine (Pinaceae) with 201 trees (20%). The oldest tree is a Copper Beach which is likely over 100 years old.