Nichols Arboretum, locally known as the Arb, is an arboretumoperated by the University of Michigan. Located on the eastern edge of its Central Campus at 1610 Washington Heights in Ann Arbor, Michigan, the Arboretum is a mosaic of University and City properties operated as one unit. The arboretum is open daily from sunrise to sunset with no charge for admission. The Huron River separates a northern section of the arboretum's floodplain woods; the railroad marks the northern border. The arboretum was designed in 1906 by O. C. Simonds, and he used the steep glacial topography to include areas both for collections and natural areas. Many of the older plantings date from the 1920s and 1930s. It is particularly known for its Peony Collection, Heathdale Collection, the Centennial Shrub Collection and the Dow Prairie. The University of Michigan conducts controlled burns of the prairie each year in an attempt to maintain native species and habitat. Students flock to the Arb for a variety of outdoor activities beyond assigned studies, such as jogging, picnicking, and sun-bathing. Maps are posted, which include the length and type of trail. The Arb is a common spot for Ann Arbor's students to gather. During winter, students have been known to go sledding in the Arb using cafeteria trays from university dining halls. In recent summers, the Arb has been the site of Shakespeare in the Arb, dramatic performances of Shakespearean plays, including A Midsummer Night's Dream and Love's Labour's Lost; the June 2012 production was The Merry Wives of Windsor.
General collection
Cedars of Lebanon - four specimens, planted 1946, at the extreme edge of their cold hardiness range.
Chinese Fringetree - believed the oldest specimen of the species in the state.
Ginkgo - the oldest trees were planted before 1920.
Conifers - planted primarily in the 1910s to 1930s. Many species of pine, spruce and fir, including ponderosa pine, lodgepole pine, Engelman spruce, and Nordman fir.
Cupressaceae - four genera planted from the 1920s-1950s: junipers, arborvitae and false cypresses.
Hackberries - several species of hackberries
Hawthorn - numerous hawthorn species, mostly from the 1920s are historically important and will be replaced.
Korean Quasibark Tree - possibly the only specimens in Michigan, planted 1933.
Larches - Japanese larches planted 1938, with a few European larches planted 1952.
Maples, Horse Chestnuts and Buckeyes - planted 1920s and 1930s. Species include Trefoil Maple, Sycamore Maple and Japanese Maple, as well as the genus Aesculus including Horsechestnuts and Buckeyes.
Oaks - native oaks including red, white, black, bur, shingle, and swamp white, as well as three Asian oaks representing sawtooth oak and oriental oak.
Turkish Hazelnut - is thriving in the Main Valley
Ulmaceae - American elms, European and Asian elms, Chinese elms, and Japanese zelkovas.
White Pines - about 150 eastern white pines were planted in 1952 and complement the much older stands throughout the Arb.
Other collections
Centennial Shrub Collection - popular ornamental shrubs and small trees including crab apple trees, hawthorn trees, a lilac collection, and spiraea.
Gateway Garden - an entry garden based on American meadows, with pools and a dry creek.
Heathdale - ericaceous and Appalachian Plants, including Catawba and Rosebay rhododendrons, azaleas, dog-hobble, mountain laurel, as well as hemlock, dogwoods, witch-hazel, and sassafras. Some date from plant collecting expeditions in the 1920s; others have been added in the past decade.
Rhododendrons - hybrid azaleas and rhododendrons hardy in Ann Arbor.
Oak Openings - a collection begun in 2001 and in its early stages. It will represent plants once common to oak openings in the Ann Arbor area.
Peony Garden - 516 peony cultivars in 27 beds, with plantings dating from 1927. It is the largest public collection of historic herbaceous peony cultivars in North America.
Natural areas
Uplands - second and third-growth woodland, mostly oak-hickory forest. The oldest oaks range from 75 to 119 years old; the oldest hickories are 109–135 years old. This area includes red, black and white oaks ; pignut hickory ; Bur oak ; white ash ; basswood ; shagbark hickory ; bitternut hickory ; and black walnut. Native understory species include ironwood, musclewood, flowering dogwood, witch-hazel, alternate-leaf dogwood, maple-leaved viburnum, and hazelnut.