The H. H. Hunnewell Arboretum is home to both native and non-native trees in habitat collections, with understory and herbaceous layers present.
Prominent features include the Grotto, Woodland Pond, Wedding Area, and a stone bench memorializing Professor Margaret Ferguson, who enjoyed the vista from this point in the arboretum. The arboretum incorporates numerous members of the Ericaceae (Heath) family: rhododenrons and azaleas (Rhododendron spp), andromeda (Pieris japonica), mountain laurel (Kalmia latifolia) and dog-hobble (Leucothoe fontanesiana). Among the notable trees are Fraser fir (Abies fraseri), Franklin tree (Franklinia alatamaha), Japanese maple (Acer palmatum), eastern white pine (Pinus strobus), pitch pine (Pinus rigida) and sawara falsecypress (Chamaecyparis pisifera). The upland woods at the east end of the arboretum is a fragment of the type of mixed oak forest one is likely to find in eastern Massachusetts.
The arboretum takes its name from Horatio Hollis Hunnewell (1810-1902), a prominent member of the philanthropic Hunnewell family. An avid horticulturist, H. H. Hunnewell popularized and cultivated cold-hardy rhododenrons and donated many to the college. His estate on Lake Waban, dating from 1852, is home to world-famous gardens of his creation, including a pinetum of rare conifers. Mr. Hunnewell and his family have been ardent supporters of Wellesley College through the years. His wife was Isabella Pratt Welles, for whose family the college and town were named. Funds for the arboretum came from his daughter, Isabella Hunnewell Shaw, who wished to share her own childhood enjoyment of the woods with students of the college.