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A3304 Tsuga canadensis - Liriodendron tulipifera Forest Alliance

Type Concept Sentence: These are acidic cove forests dominated by Tsuga canadensis and mesic hardwoods, most constantly Liriodendron tulipifera, found primarily in the Southern Blue Ridge and north to New Jersey, but also ranging into widely scattered areas of the Interior Low Plateau and Cumberlands, where stands containing Tsuga canadensis may be notably disjunct from its main range in the north.

Common (Translated Scientific) Name: Eastern Hemlock - Tuliptree Forest Alliance

Colloquial Name: Southern Hemlock - Tuliptree Forest

Hierarchy Level:  Alliance

Type Concept: Forests in this alliance are acidic cove forests dominated by Tsuga canadensis, occurring with various hardwood species of mesic forests, including Betula lenta, Fagus grandifolia, Fraxinus americana, Halesia tetraptera, Liriodendron tulipifera, Magnolia acuminata, Quercus rubra, and Tilia americana var. heterophylla, and others. Common shrubs are Kalmia latifolia, Leucothoe fontanesiana, and Rhododendron maximum. Herbaceous cover is typically sparse and includes acid-loving species such as Galax urceolata, Goodyera pubescens, Hexastylis sp., Polystichum acrostichoides, Thelypteris noveboracensis, and Tiarella cordifolia. They are found primarily in the Southern Blue Ridge, but also ranging into widely scattered areas of the Interior Low Plateau and Cumberlands, where stands containing Tsuga canadensis may be notably disjunct from its main range in the north. These forests occur in deep coves, moist flats, and ravines but are occasionally found along larger stream bottoms, typically at elevations below 1068 m (3500 feet).

Diagnostic Characteristics: Codominance by Tsuga canadensis is characteristic, within the alliance''s range in the Southern Appalachians and adjacent ecoregions to the south.

Rationale for Nominal Species or Physiognomic Features: No Data Available

Classification Comments: Most associations included here are mesic uplands. A few have been placed in "temporarily flooded" but the degree of actual flooding involved here is questionable. This hydrologic or landform variation may be regarded as loosely defining two suballiances. Description is most strongly based on the old alliance Tsuga canadensis - Liriodendron tulipifera Forest Alliance (A.413).

Similar NVC Types: No Data Available
note: No Data Available
Physiognomy and Structure: These are closed-canopy acidic cove forests and other related mesic to moist forests with moderately closed shrub layers and sparse herbaceous layers.

Floristics: Forests in this alliance are dominated by Tsuga canadensis, occurring with various hardwood species of mesic forests, including Betula lenta, Fagus grandifolia, Fraxinus americana, Halesia tetraptera, Liriodendron tulipifera, Magnolia acuminata, Quercus rubra, and Tilia americana var. heterophylla, and others. Common shrubs are Kalmia latifolia, Leucothoe fontanesiana, and Rhododendron maximum. Herbaceous cover is typically sparse and includes acid-loving species such as Chimaphila maculata, Galax urceolata, Goodyera pubescens, Hexastylis sp., Mitchella repens, Polystichum acrostichoides, Thelypteris noveboracensis, Tiarella cordifolia, and Viola blanda. Moister examples, found along montane streams and terraces, are dominated by Tsuga canadensis or codominated by Tsuga canadensis and Pinus strobus. These forests often have dense ericaceous shrub layers dominated by Rhododendron maximum and/or Leucothoe fontanesiana.

Dynamics:  Tsuga canadensis is currently threatened by the hemlock woolly adelgid (Adelges tsugae), a sap-sucking bug accidentally introduced from East Asia to the United States in 1924, and first found in the native range of eastern hemlock in the late 1960s. The adelgid has spread very rapidly in southern parts of the range once becoming established, while its expansion northward is much slower. Attempts to save representative examples on both public and private lands are on-going. Virtually all the hemlocks in the southern Appalachian Mountains have seen infestations of the insect, with thousands of hectares of stands dying within since about 2009. A 2009 study conducted by scientists with the U.S. Forest Service Southern Research Station suggests the hemlock woolly adelgid is killing hemlock trees faster than expected in the Southern Appalachians, and rapidly altering the carbon cycle of these forests. According to Science Daily, the pest could kill most of the region''s hemlock trees by about 2020.
Environmental Description:  These habitats are generally known as acidic cove forests. Stands are primarily found in deep coves, moist flats, and ravines but are occasionally found along larger stream bottoms, typically at elevations below 1068 m (3500 feet). The moister associations placed here are found along montane streams and terraces in the Southern Appalachians and Cumberland Mountains of the southeastern United States. Soils are generally acidic, nutrient-poor, and usually moderately well-drained such as sandy loams.
Geographic Range: This alliance is found in the Southern Blue Ridge and adjacent ecoregions, ranging into widely scattered areas of the Interior Low Plateau and Cumberlands of Alabama, Indiana, Kentucky, and Tennessee, and north into Pennsylvania and the New Jersey highlands.

Nations: US

States/Provinces:  AL, GA, IN, KY, MD, NC, NJ, OH, PA, SC, TN, VA, WV


Confidence Level: Moderate

Confidence Level Comments: No Data Available
Grank: GNR

Greasons: No Data Available
Type Name Database Code Classification Code
Class 1 Forest & Woodland Class C01 1
Subclass 1.B Temperate & Boreal Forest & Woodland Subclass S15 1.B
Formation 1.B.2 Cool Temperate Forest & Woodland Formation F008 1.B.2
Division 1.B.2.Na Eastern North American Forest & Woodland Division D008 1.B.2.Na
Macrogroup 1.B.2.Na.3 Appalachian-Interior-Northeastern Mesic Forest Macrogroup M883 1.B.2.Na.3
Group 1.B.2.Na.3.a American Beech - Tuliptree - Yellow Buckeye Forest Group G020 1.B.2.Na.3.a
Alliance A3304 Eastern Hemlock - Tuliptree Forest Alliance A3304 1.B.2.Na.3.a
Association CEGL004767 Eastern Hemlock - (Tuliptree, American Beech) / Bigleaf Magnolia / Christmas Fern Forest CEGL004767 1.B.2.Na.3.a
Association CEGL005043 Eastern Hemlock - American Beech - Sugar Maple / (American Witch-hazel, Mountain Laurel) Forest CEGL005043 1.B.2.Na.3.a
Association CEGL006304 Tuliptree - Eastern White Pine - Eastern Hemlock - Northern Red Oak / Christmas Fern Forest CEGL006304 1.B.2.Na.3.a
Association CEGL006474 Eastern Hemlock - American Beech - (Chestnut Oak, White Oak) Forest CEGL006474 1.B.2.Na.3.a
Association CEGL006923 Eastern Hemlock - Chestnut Oak - Sweet Birch Forest CEGL006923 1.B.2.Na.3.a
Association CEGL007102 Eastern White Pine - Eastern Hemlock / Great Laurel - (Highland Doghobble) Forest CEGL007102 1.B.2.Na.3.a
Association CEGL007136 Eastern Hemlock / Great Laurel - (Mountain Sweet-pepperbush, Highland Doghobble) Forest CEGL007136 1.B.2.Na.3.a
Association CEGL007543 Tuliptree - Sweet Birch - Eastern Hemlock / Great Laurel Forest CEGL007543 1.B.2.Na.3.a
Association CEGL007693 Eastern Hemlock - Mountain Silverbell - Mountain Magnolia / Great Laurel / Intermediate Woodfern Forest CEGL007693 1.B.2.Na.3.a
Association CEGL008407 Eastern Hemlock - (American Beech, Appalachian Basswood) / Umbrella-tree Forest CEGL008407 1.B.2.Na.3.a
Association CEGL008512 Tuliptree - Chestnut Oak - (Eastern Hemlock) / Mountain Laurel - (Catawba Rosebay) Forest CEGL008512 1.B.2.Na.3.a
Association CEGL008558 Red Maple - Sweet Birch - Mountain Magnolia / (Great Laurel, Mountain Laurel) Ruderal Forest CEGL008558 1.B.2.Na.3.a
Concept Lineage: A. 413 (8/11) plus A.171, and one association from A.127.

Predecessors: No Data Available

Obsolete Names: No Data Available

Obsolete Parents: No Data Available
Synonomy: ? Pinus - Tsuga (Morey 1936)
? beech-hemlock association (Morey 1936)
Concept Author(s): M. Pyne, in Faber-Langendoen et al. (2013)

Author of Description: M. Pyne

Acknowledgements: We have incorporated significant descriptive information previously compiled by Michael Schafale, Alan Weakley, Steve Simon, and Gary Kauffman.

Version Date: 01-08-14
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