Visiting New Hampshire's Biodiversity


Manchester Cedar Swamp


Description: The Manchester Cedar Swamp is a 602-acre ecological preserve at Hackett Hill, and is one of the state's most significant ecological areas. The trail network passes through a wide variety of uncommon natural communities, including an Atlantic white cedar swamp and patches of giant rhododendron. Early summer is the best time to catch the rhododendron in bloom. 

Atlantic white cedar (Chamaecyparis thyoides) ranges from southern Maine to Florida and the Gulf of Mexico, mainly in freshwater wetlands along the coast. It is a relatively long-lived species that can exceed 300 years of age. In New Hampshire, the oldest known living tree of this species is about 215 years old. Atlantic white cedar is sometimes found in association with black gum (Nyssa sylvatica), another very long-lived tree species that also occurs in the Manchester Cedar Swamp complex.

With a combined total of less than 500 acres, Atlantic white cedar swamps are one of the rarest wetland types in New Hampshire. Only four of the state’s unique Atlantic white cedar swamps are larger than 40 acres (Manchester Cedar Swamp is 42 acres). Atlantic white cedar swamps provide critical habitat for many plant and animal species, some of which are very rare in the state.

Four different kinds of Atlantic white cedar swamps have been described in New Hampshire. The type at Manchester Cedar Swamp is the globally rare Atlantic white cedar - giant rhododendron swamp. It occurs at fewer than ten swamps in New England, and this is the only one north of Massachusetts. In parts of this community, giant rhododendron (Rhododendron maximum) shrubs form a strikingly dense understory beneath a tree canopy composed primarily of Atlantic white cedar trees (however, little rhododendron grows in the particular basin that the boardwalk trail passes through at this site).


Directions: From I-93 north of Manchester, take Exit 10 and head south on West River Road (a.k.a. Front Street). Go about 1 mile (crossing the town line from Hooksett into Manchester) and turn right (west and north) onto Hackett Hill Road. Travel approx. 0.7 miles and turn left (west) onto Countryside Blvd. Go about half a mile to where the road just starts to curve right. The preserve entrance/trailhead is on the left. Reverse direction and park along the south side of the road.

Landowner: The Nature Conservancy

Site Guide and Map

Woodland Loop Trail at Manchester Cedar Swamp (photo by Ben Kimball for the NH Natural Heritage Bureau) Rhododendron maximum (giant rhododendron) leaves and flowers (photo by Ben Kimball for the NH Natural Heritage Bureau) Atlantic white cedar - giant rhododendron swamp (photo by Ben Kimball for the NH Natural Heritage Bureau)

Cedar Loop Trail at Manchester Cedar Swamp (photo by Ben Kimball for the NH Natural Heritage Bureau) fertile stems of Osmunda cinnamomea (cinnamon fern) (photo by Ben Kimball for the NH Natural Heritage Bureau)

Rhododendron maximum (giant rhododendron) leaves (photo by Ben Kimball for the NH Natural Heritage Bureau) Rock with Rhododendron maximum (giant rhododendron) (photo by Ben Kimball for the NH Natural Heritage Bureau)

Kalmia latifolia (mountain laurel) (photo by Ben Kimball for the NH Natural Heritage Bureau) Glacial erratic boulder in the woods at Manchester Cedar Swamp (photo by Ben Kimball for the NH Natural Heritage Bureau)

Nyssa sylvatica (black gum) is an uncommon tree that can be found at Manchester Cedar Swamp (photo by Ben Kimball for the NH Natural Heritage Bureau) Gaultheria procumbens (wintergreen) in flower and fruit at Manchester Cedar Swamp (photo by Ben Kimball for the NH Natural Heritage Bureau) Rhododendron maximum (giant rhododendron) in bloom at Manchester Cedar Swamp (photo by Ben Kimball for the NH Natural Heritage Bureau)

Rhododendron maximum (giant rhododendron) (photo by Ben Kimball for the NH Natural Heritage Bureau) preserve entrance sign (photo by Ben Kimball for the NH Natural Heritage Bureau)

Monotropa uniflora (Indian pipes) (photo by Ben Kimball for the NH Natural Heritage Bureau)



Site Guide 

link: nature.org/wherewework/northamerica/states/newhampshire/preserves/art6252.html

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