Print Report

A3828 Picea mariana - Larix laricina / Alnus incana Swamp Forest Alliance

Type Concept Sentence: This rich black spruce - tamarack swamp alliance is dominated by boreal conifers with minerotrophic indicators such as Alnus incana. It is found in eastern Canada, excluding the Atlantic boreal region, and adjacent northern regions of the northeastern United States from the western Great Lakes to northern New England.

Common (Translated Scientific) Name: Black Spruce - Tamarack / Gray Alder Swamp Forest Alliance

Colloquial Name: Black Spruce - Tamarack Intermediate Swamp Forest

Hierarchy Level:  Alliance

Type Concept: This rich black spruce - tamarack swamp alliance is found in eastern Canada, excluding the Atlantic boreal region, and adjacent northern regions of the northeastern United States from the western Great Lakes to northern New England. It is dominated by Picea mariana, Larix laricina, and Abies balsamea, with occasional Betula papyrifera or Picea glauca. The broad-leaved shrub layer is typically dense, dominated by Alnus incana, with moderate to abundant low ericaceous shrubs such as Ledum groenlandicum. The sphagnum layer is partially to fully developed. In the herb layer, minerotrophic species such as Carex spp., Mitella nuda, Ribes spp., and Rubus pubescens are commonly present.

Diagnostic Characteristics: The vegetation is dominated by Picea mariana, Larix laricina, and Abies balsamea, with occasional Betula papyrifera or Picea glauca. Northern hardwood and conifer species such as Acer rubrum, Betula alleghaniensis, and Tsuga canadensis are essentially absent. Moderate to abundant Alnus incana and Ledum groenlandicum dominate the understory. The sphagnum layer is well-developed, and ericaceous shrubs are moderately common. Minerotrophic species such as Carex spp., Mitella nuda, Ribes spp., and Rubus pubescens are commonly present.

Rationale for Nominal Species or Physiognomic Features: No Data Available

Classification Comments: The role of Thuja occidentalis in this alliance needs review. Canadian review suggests that Thuja-dominated stands should be placed elsewhere, but no other appropriate alliance currently exists, unless they are placed in ~Laurentian-Acadian Alkaline Swamp Group (G046)$$, a northern temperate swamp group. Atlantic region intermediate-rich swamps are placed in their own alliance and are rich in Osmunda cinnamomea.

Similar NVC Types: No Data Available
note: No Data Available
Physiognomy and Structure: Tree canopy is typically >10 m and moderately open to closed. The sphagnum layer varies from 50-100%. A strong broad-leaved shrub layer is present, with or without an ericaceous shrub component.

Floristics: The vegetation is dominated by Picea mariana, Larix laricina, and Abies balsamea, with occasional Betula papyrifera or Picea glauca. Northern hardwood and conifer species such as Acer rubrum, Betula alleghaniensis, and Tsuga canadensis are essentially absent. The broad-leaved shrub layer is typically dense, dominated by Alnus incana, with moderate to abundant low ericaceous shrubs such as Ledum groenlandicum. The sphagnum layer is partially to fully developed. In the herb layer, minerotrophic species such as Carex spp., Mitella nuda, Ribes spp., and Rubus pubescens are commonly present.

Dynamics:  No Data Available
Environmental Description:  Stands are found on poorly drained sites, usually with intermediate to alkaline, organic soils but sometimes on wet mineral soils (Sytsma and Pippen 1981b, Sims et al. 1989). Most stands of this alliance have moderate to rich nutrient status (MNNHP 1993). Fires can spread through stands of this alliance in dry years and kill many of the thin-barked Larix laricina. Insect infestations, notably by the larch sawfly, can also cause great damage (Eyre 1980).
Geographic Range: This rich black spruce - tamarack swamp alliance is found in eastern Canada, excluding the Atlantic boreal region, and adjacent northern regions of the northeastern United States from the western Great Lakes to northern New England.

Nations: CA,US

States/Provinces:  MB?, ME?, MI?, MN, NB, NF, NH?, NS, NY?, ON, QC, VT?, WI?


Confidence Level: Low

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.5 Boreal Flooded & Swamp Forest Formation F036 1.B.5
Division 1.B.5.Na North American Boreal Flooded & Swamp Forest Division D016 1.B.5.Na
Macrogroup 1.B.5.Na.2 North American Boreal Flooded & Rich Swamp Forest Macrogroup M300 1.B.5.Na.2
Group 1.B.5.Na.2.b Ontario-Québec Boreal Flooded & Rich Swamp Forest Group G809 1.B.5.Na.2.b
Alliance A3828 Black Spruce - Tamarack / Gray Alder Swamp Forest Alliance A3828 1.B.5.Na.2.b
Association CEGL005491 Black Spruce - Tamarack / Small Cranberry / Peatmoss species Swamp Forest CEGL005491 1.B.5.Na.2.b
Concept Lineage: New alliance, but some relation to Larix laricina Saturated Forest Alliance (A.349)

Predecessors: No Data Available

Obsolete Names: No Data Available

Obsolete Parents: No Data Available
Synonomy: = Intermediate conifer swamp: Black Spruce/Tall Shrub/Labrador Tea (Harris et al. 1996) [(W29)]
= Intermediate conifer swamp: Conifer/Tall Shrub/Herb-rich (Harris et al. 1996) [(W30)]
> Poor conifer swamp: Black Spruce/Labrador Tea/Bluejoint Grass (Harris et al. 1996)
> Poor conifer swamp: Black Spruce/Labrador Tea/Sphagnum (Harris et al. 1996)
> Semi-treed bog: Black Spruce/Ericaceous Shrub/Sphagnum (Harris et al. 1996)
? Tamarack: 38 (Eyre 1980)
> Treed Bog: Black Spruce/Ericaceous Shrub/Sphagnum (Harris et al. 1996)
Concept Author(s): A.G. Harris et al. (1996)

Author of Description: D. Faber-Langendoen

Acknowledgements: We have incorporated significant descriptive information previously compiled by K. Baldwin.

Version Date: 09-26-14
  • Brewer, R. 1966. Vegetation of two bogs in southwestern Michigan. The Michigan Botanist 5(1):36-46.
  • Eyre, F. H., editor. 1980. Forest cover types of the United States and Canada. Society of American Foresters, Washington, DC. 148 pp.
  • Faber-Langendoen, D., J. Drake, M. Hall, G. Kittel, S. Menard, C. Nordman, M. Pyne, M. Reid, M. Russo, K. Schulz, L. Sneddon, K. Snow, and J. Teague. 2013-2019b. Screening alliances for induction into the U.S. National Vegetation Classification: Part 1 - Alliance concept review. NatureServe, Arlington, VA.
  • Faber-Langendoen, D., and Midwest State Natural Heritage Program Ecologists. 1996. Terrestrial vegetation of the midwest United States. International classification of ecological communities: Terrestrial vegetation of the United States. The Nature Conservancy, Arlington, VA.
  • Harris, A. G., S. C. McMurray, P. W. C. Uhlig, J. K. Jeglum, R. F. Foster, and G. D. Racey. 1996. Field guide to the wetland ecosystem classification for northwestern Ontario. Ontario Ministry of Natural Resources, Northwest Science and Technology, Thunder Bay, Ontario. Field guide FG-01. 74 pp. plus appendix.
  • MNNHP [Minnesota Natural Heritage Program]. 1993. Minnesota''s native vegetation: A key to natural communities. Version 1.5. Minnesota Department of Natural Resources, Natural Heritage Program, St. Paul, MN. 110 pp.
  • Sims, R. A., W. D. Towill, K. A. Baldwin, and G. M. Wickware. 1989. Field guide to the forest ecosystem classification for northwestern Ontario. Ontario Ministry of Natural Resources, Toronto. 191 pp.
  • Sytsma, K. J., and R. W. Pippen. 1981b. The Hampton Creek wetland complex in southwestern Michigan. I. History and physical features. The Michigan Botanist 20:137-142.
  • Zoladeski, C. A., G. M. Wickware, R. J. Delorme, R. A. Sims, and I. G. W. Corns. 1995. Forest ecosystem classification for Manitoba: Field guide. Special Report 2. Natural Resources Canada, Canadian Forest Service, Northwest Region, Northern Forestry Center, Edmonton, Alberta.