Index of Species Information
SPECIES: Chamaedaphne calyculata
SPECIES: Chamaedaphne calyculata
AUTHORSHIP AND CITATION :
Pavek, Diane S. 1993. Chamaedaphne calyculata. In: Fire Effects Information System, [Online].
U.S. Department of Agriculture, Forest Service,
Rocky Mountain Research Station, Fire Sciences Laboratory (Producer).
Available: http://www.fs.fed.us/database/feis/ .
Cassandra calyculata (L.) D. Don.
SCS PLANT CODE :
COMMON NAMES :
The currently accepted scientific name of leatherleaf is Chamaedaphne
calyculata (L.) Moench. It is in the heather family (Ericaceae)
[25,36,44]. Recognized varieties are :
C. c. var. calyculata
C. c. var. angustifolia (Ait.) Rehd.
C. c. var. latifolia (Ait.) Fern.
LIFE FORM :
FEDERAL LEGAL STATUS :
No special status
OTHER STATUS :
Leatherleaf was listed as threatened in Illinois in 1989 by the Illinois
Endangered Species Protection Board .
DISTRIBUTION AND OCCURRENCE
SPECIES: Chamaedaphne calyculata
GENERAL DISTRIBUTION :
Leatherleaf is circumboreal and is found throughout Alaska and Canada
. Its distribution extends southward through the Lake States and
the northeastern United States [25,70].
FRES10 White - red - jack pine
FRES11 Spruce - fir
FRES19 Aspen - birch
AK CT IL IN IA ME MA MI MN NH
NJ NY NC ND OH RI VT WI AB BC
MB NB NF NT NS ON PE PQ SK YT
BLM PHYSIOGRAPHIC REGIONS :
KUCHLER PLANT ASSOCIATIONS :
K093 Great Lakes spruce - fir forest
K094 Conifer bog
K095 Great Lakes pine forest
K096 Northeastern spruce - fir forest
K106 Northern hardwoods
K107 Northern hardwoods - fir forest
K108 Northern hardwoods - spruce forest
K110 Northeastern oak - pine forest
SAF COVER TYPES :
1 Jack pine
5 Balsam fir
12 Black spruce
13 Black spruce - tamarack
19 Gray birch - red maple
21 Eastern white pine
37 Northern white-cedar
45 Pitch pine
97 Atlantic white-cedar
107 White spruce
SRM (RANGELAND) COVER TYPES :
HABITAT TYPES AND PLANT COMMUNITIES :
Leatherleaf is a dominant shrub in seral dwarf-shrub wetland communities
[15,16,48]. Leatherleaf occurs in pure stands on floating mats and in
mixed stands that are grounded . Leatherleaf associations are the
most extensive communities in the bogs of the Lake States. Several
subtypes of leatherleaf associations have been described for New England
peatlands . Sphagnum-leatherleaf community types have been
described for this region and Canada . Leatherleaf is usually
present in the tall-shrub community types of bogs or heathlands [20,76].
In central and northern Canada, leatherleaf has been included in various
open black spruce (Picea mariana) vegetation types [17,43,49,73].
Leatherleaf is named as a dominant or indicator species in the following
(1) Ecology of peat bogs of the glaciated northeastern United States:
A community profile 
(2) Community classification of the vascular vegetation of a New
Hampshire peatland 
(3) Plant communities of Voyageurs National Park, Minnesota, U.S.A. .
Species associated with leatherleaf that are not mentioned above are
codominant shrubs such as bog kalmia (Kalmia polifolia), sheep laurel
(K. angustifolia), bog labrador tea (Ledum groenlandica), blueleaf
bog-rosemary (Andromeda glaucophylla), bog cranberry (Vaccinium
oxycoccos), and sweet gale (Myrica gale) [20,48,55,73,76]. Other
species occurring with leatherleaf are roundleaf sundew (Drosera
rotundifolia), pitcherplant (Sarracenia purpurea), and sedges (Carex
SPECIES: Chamaedaphne calyculata
IMPORTANCE TO LIVESTOCK AND WILDLIFE :
Leatherleaf is browsed and used for nesting by wildlife. It was a minor
part of white-tailed deer winter browse in New Jersey . Leatherleaf
was consumed in small amounts by caribou in Michigan and northern Canada
[14,61,67,69]. Sharp-tailed grouse browsed leatherleaf twigs during the
winter in Wisconsin . Moose occasionally browsed leatherleaf from
June to November on the Kenai Peninsula, Alaska . Mallards nest in
leatherleaf in North Dakota . Leatherleaf occurred in cover types
used year-round by ruffed grouse .
NUTRITIONAL VALUE :
Current year's growth of leatherleaf that was collected in July and
August in southeastern Manitoba had 7.5 percent crude protein, 48.1
percent acid detergent fiber, and 49.3 percent dry matter digestibility.
One-year-old leaves had slightly more crude protein (8.0 percent) and
less acid detergent fiber (33.4 percent) and dry matter digestibility
(44.3 percent) .
COVER VALUE :
VALUE FOR REHABILITATION OF DISTURBED SITES :
Leatherleaf reclaimed large areas in raised bogs in the eastern United
States that had been denuded by commercial peat removal over the past 4
to 92 years . Seven years after powerline construction in a treed
bog in northern Manitoba, leatherleaf had two times more biomass than
other shrubs present. It had a frequency of 78 percent in disturbed
areas and 94 percent in the control . In the Pinhook Bog of
Indiana, sphagnum mats containing leatherleaf were successfully
transplanted to other bog areas that had been killed by runoff from
stockpiled road salt .
OTHER USES AND VALUES :
OTHER MANAGEMENT CONSIDERATIONS :
Leatherleaf greatly increases following clearcutting; leatherleaf and
other shrubs can suppress black spruce on medium to poor sites . In
Minnesota, leatherleaf and other shrubs rapidly increased after tree
harvest; however, restocking was not affected by shrub density 4 to 6
years after harvest . Despite dense leatherleaf in a black spruce
swamp in Ontario, relative regeneration rates of black spruce were high
. There was no difference in stocking rates on nine burned and
unburned cutover black spruce sites in northern Minnesota; seedbed cover
by leatherleaf and bog labrador tea was at acceptable levels .
Control of leatherleaf by herbicides has been discussed .
Aboveground biomass of leatherleaf was estimated at 136.7 pounds per
acre (122 kg/ha) for wildlife browse and ground fuels in open black
spruce bogs in Nova Scotia .
Transplanting leatherleaf in summer or autumn stimulated shoot
production more than spring transplanting .
BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Chamaedaphne calyculata
GENERAL BOTANICAL CHARACTERISTICS :
Leatherleaf is a native evergreen shrub that grows up to 4.9 feet (1.5
m) tall [25,43]. Its woody rhizome extends down an average of 12.6
inches (32 cm) into organic matter . Leatherleaf has many branches
and forms dense thickets of up to 18.6 stems per square foot (200
stems/sq m) [10,33]. Average basal diameter of leatherleaf stems is
0.27 inch (0.68 cm) . The one-sided racemes have 1 to 15 or more
flowers that form persistent, many-seeded capsules [10,43,65].
RAUNKIAER LIFE FORM :
REGENERATION PROCESSES :
Moist sphagnum surrounding leatherleaf shoots, roots, and rhizomes
causes vigorous vegetative growth [5,26]. Sphagnum grows on leatherleaf
stems and branches but does not inhibit growth [12,18]. Ice will break
up leatherleaf shrubs, resulting in rapid expansion of colonies .
Leatherleaf establishes in windfall areas .
Leatherleaf seed set is usually high (50 to 95 percent). Seed set
decreased when insects such as bombus bees were excluded from flowers.
When self-fertilized, leatherleaf has low seed set (1 to 15 percent)
. Leatherleaf seeds germinate on sphagnum or sedge mats .
SITE CHARACTERISTICS :
Leatherleaf is a true bog species and is found in practically all boreal
bogs . It occurs in lowland sites, treed or treeless bogs,
peatlands, sedge fens and meadows, black spruce muskegs, and kettle pond
edges [2,19,55,59]. It is found at elevations up to 5,300 feet (1,615
Sites are often poorly drained or have standing water [48,63].
Leatherleaf is acid tolerant and usually occurs where the pH is less
than 5; it needs acidic conditions to become dominant [11,38,66]. It
commonly occurs in drier areas on sedge mats that may be floating or in
wet peat that is up to 43 feet (13 m) thick [12,16,38,55,83].
Leatherleaf is found on very moist ombrotrophic or minerotrophic sites
with low nutrients [3,4,7]. It occurs on substrates such as thin till
overlain with sandy loam or fine loamy clays with varying depths of
humus, or on entirely organic substrates [7,30,43]. Permafrost is often
discontinuous and can be shallow where leatherleaf grows [6,8,58].
Leatherleaf is found in maritime to continental climates with extreme
seasonal variations in temperature [8,34]. Leatherleaf grows poorly on
exposed sites with severe winters [16,33].
SUCCESSIONAL STATUS :
Although leatherleaf is not a pioneer mat former, it is a primary
species in extending the bog mat [11,16,22,62]. It is the first shrub
to enter a bog community after sphagnum is established [11,53].
Leatherleaf is characteristic of the mature and late stages of moss-low
ericaceous shrub communities as open water in a bog sere disappears. It
may dominate for 50 years in some communities [11,18,31].
Leatherleaf is shade intolerant [53,77]. Leatherleaf stands begin to thin
as tall shrubs or bog forest species such as tamarack (Larix laricina)
and/or black spruce establish [11,33,35,63,73].
SEASONAL DEVELOPMENT :
Leatherleaf flowers from March to July from buds formed the previous
growing season [10,25,47,75]. Fruits develop in late summer and fall
SPECIES: Chamaedaphne calyculata
FIRE ECOLOGY OR ADAPTATIONS :
Leatherleaf's persistence in communities over long periods of time has
been attributed to its regeneration following fire . Its rhizomes
are buried deep in the mineral soil and survive all but the most severe
fires . Depth of rhizomes and season of fire affect leatherleaf
shoot growth and recovery. Leatherleaf rhizomes were collected in
spring, summer, and autumn and subjected to wet heat treatments from 113
to 140 degrees Fahrenheit (45-60 deg C). All autumn-collected rhizomes
died after treatment. Summer-collected rhizomes produced fewer shoots
than spring-collected; both had significantly (p<0.05) fewer shoots than
the controls .
Bogs are usually too wet to burn except during drought . Fire is a
primary factor disrupting boreal treed bog succession; leatherleaf
invades after fires remove the tree associations [9,22,28,33].
Recurrent fires at approximately 50-year intervals in New England
leatherleaf bogs or on peat surfaces controls tree invasion . Fire
recurrence in a New Brunswick bog was 370 years .
FIRE REGIMES :
Find fire regime information for the plant communities in which this
species may occur by entering the species name in the FEIS home page under
"Find Fire Regimes".
POSTFIRE REGENERATION STRATEGY :
Rhizomatous low woody plant, rhizome in organic mantle
Surface rhizome/chamaephytic root crown
Rhizomatous shrub, rhizome in soil
Secondary colonizer - off-site seed
SPECIES: Chamaedaphne calyculata
IMMEDIATE FIRE EFFECT ON PLANT :
Fire top-kills leatherleaf. Leatherleaf probably survives severe fires
because rhizomes are deep in water-saturated substrates and its stems
are matted in debris [28,33]. Surviving root crowns and rhizomes
DISCUSSION AND QUALIFICATION OF FIRE EFFECT :
PLANT RESPONSE TO FIRE :
Leatherleaf was only slightly injured by summer or autumn fires in New
Brunswick. Following spring burning, leatherleaf showed a strong
increase in stem density; apparently, it had not yet depleted its
reserves and was able to support new growth. Preburn and postburn
percent relative abundance (stem density) after spring, summer, and
autumn fires was as follows [26,29]:
Season of Postburn
burn Preburn 1 month 3 months 5 months
Spring 28 42 13 --
Summer 30 29 29 17
Autumn 36 32 -- --
Ten years after a lightning fire in Alaska, leatherleaf was present in
low amounts on disturbed firelines and in one burned site . It was
present at 0.7 percent frequency in burned and at 2 percent frequency in
unburned areas 20 to 24 years following fire in the Northwest
Territories . In northern Quebec, leatherleaf occurred 30 years
after fire at 21 to 31 percent frequency in lowland boreal black spruce
forest and at 1 to 20 percent in forest-tundra sites . Leatherleaf
had about 40 percent frequency 94 years following a high-severity fire
in central New York .
DISCUSSION AND QUALIFICATION OF PLANT RESPONSE :
FIRE MANAGEMENT CONSIDERATIONS :
Leatherleaf is a flammable shrub; crowning or foliage scorch is common
with leatherleaf in the understory in the pine swamps or lowlands of New
Jersey . Fuel loading that was predominantly leatherleaf and bog
labrador tea in cutover areas of black spruce was estimated at 15 to 25
tons per acre (33-56 t/ha) in the Blackduck Burns, Minnesota .
SPECIES: Chamaedaphne calyculata
1. Aksamit, Scott E.; Irving, Frank D. 1984. Prescribed burning for lowland
black spruce regeneration in northern Minnesota. Canadian Journal of
Forest Research. 14: 107-113. 
2. Argus, George W. 1966. Botanical investigations in northeastern
Saskatchewan: the subarctic Patterson-Hasbala Lakes region. Canadian
Field-Naturalist. 80(3): 119-143. 
3. Boelter, Don H.; Verry, Elon S. 1977. Peatland and water in the northern
Lake States. Gen. Tech. Rep. NC-31. St. Paul, MN: U.S. Department of
Agriculture, Forest Service, North Central Forest Experiment Station.
22 p. 
4. Brand, Gary J. 1985. Environmental indices for common Michigan trees and
shrubs. Res. Pap. NC-261. St. Paul, MN: U.S. Department of Agriculture,
Forest Service, Northcentral Forest Experiment Station. 5 p. 
5. Bray, William L. 1920. The history of forest development on an undrained
sand plain in the Adirondacks. Syracuse, NY: New York State College of
Forestry. 47 p. 
6. Brown, K. R.; Zobel, D. B.; Zasada, J. C. 1988. Seed dispersal, seedling
emegence, and early survival of Larix laricina (DuRoi) K. Koch in the
Tanana Valley, Alaska. Canadian Journal of Forest Research. 18: 306-314.
7. Brumelis, G.; Carleton, T. J. 1989. The vegetation of post-logged black
spruce lowlands in central Canada. II. Understory vegetation. Journal of
Applied Ecology. 26: 321-339. 
8. Calmes, Mary A. 1976. Vegetation pattern of bottomland bogs in the
Fairbanks area, Alaska. Fairbanks, AK: University of Alaska. 104 p.
9. Chandler, Craig; Cheney, Phillip; Thomas, Philip; [and others}. 1983.
Fire in forestry: Vol. I. Forest fire behavior and effects. New York:
John Wiley & Sons. 450 p. 
10. Chapman, William K.; Bessette, Alan E. 1990. Trees and shrubs of the
Adirondacks. Utica, NY: North Country Books, Inc. 131 p. 
11. Conway, Verona M. 1949. The bogs of central Minnesota. Ecological
Monographs. 19(2): 173-206. 
12. Cooper, William S. 1913. The climax forest of Isle Royale, Lake
Superior, and its development. III. Botanical Gazette. 55(3): 189-235.
13. Cowardin, Lewis M.; Gilmer, David S.; Shaiffer, Charles W. 1985. Mallard
recruitment in the agricultural environment of North Dakota. Wildlife
Monographs No. 92. Washington, DC: The Wildlife Society. 37 p. 
14. Cringan, Alexander Thom. 1957. History, food habits and range
requirements of the woodland caribou of continental North America.
Transactions, North American Wildlife Conference. 22: 485-501. 
15. Cronan, Christopher S.; DesMeules, Marc R. 1985. A comparison of
vegetative cover and tree community structure in three forested
Adirondack watersheds. Canadian Journal of Forest Research. 15: 881-889.
16. Damman, Antoni W. H.; French, Thomas W. 1987. The ecology of peat bogs
of the glaciated northeastern United States: a community profile.
Biological Report 85(7.16). Washington, DC: U.S. Department of the
Interior, Fish and Wildlife Service, Research and Development, National
Wetlands Research Center. 100 p. 
17. Dansereau, Pierre. 1959. The principal plant associations of the Saint
Lawrence Valley. No. 75. Montreal, Canada: Contrib. Inst. Bot. Univ.
Montreal. 147 p. 
18. Dansereau, Pierre; Segadas-Vianna, Fernando. 1952. Ecological study of
the peat bogs of eastern North America. Canadian Journal of Botany.
30(5): 490-520. 
19. Drury, William H., Jr. 1956. Bog flats and physiographic processes in
the Upper Kuskokwim River region, Alaska. Contributions from the Gray
Herbarium No. 178. Cambridge, MA: Harvard University, The Gray
Herbarium. 127 p. 
20. Dunlop, D. A. 1987. Community classification of the vascular vegetation
of a New Hampshire peatland. Rhodora. 89(860): 415-440. 
21. Ehrenfeld, Joan G. 1986. Wetlands of the New Jersey Pine Barrens: the
role of species composition in community function. American Midland
Naturalist. 115(2): 301-313. 
22. Elliott-Fisk, Deborah L. 1988. The boreal forest. In: Barbour, Michael
G.; Billings, William Dwight, eds. North American terrestrial
vegetation. Cambridge; New York: Cambridge University Press: 33-62.
23. Eyre, F. H., ed. 1980. Forest cover types of the United States and
Canada. Washington, DC: Society of American Foresters. 148 p. 
24. Famous, Norman C.; Spencer, M. 1989. Revegetation patterns in mined
peatlands in central and eastern North America studied. Restoration and
Management Notes. 7(2): 95-96. 
25. Fernald, Merritt Lyndon. 1950. Gray's manual of botany. [Corrections
supplied by R. C. Rollins]. Portland, OR: Dioscorides Press. 1632 p.
(Dudley, Theodore R., gen. ed.; Biosystematics, Floristic & Phylogeny
Series; vol. 2). 
26. Flinn, Marguerite Adele. 1980. Heat penetration and early postfire
regeneration of some understory species in the Acadian forest. Halifax,
NB: University of New Brunswick. 87 p. Thesis. 
27. Flinn, Marguerite A.; Pringle, Joan K. 1983. Heat tolerance of rhizomes
of several understory species. Canadian Journal of Botany. 61: 452-457.
28. Flinn, Marguerite A.; Wein, Ross W. 1977. Depth of underground plant
organs and theoretical survival during fire. Canadian Journal of Botany.
55: 2550-2554. 
29. Flinn, Marguerite A.; Wein, Ross W. 1988. Regrowth of forest understory
species following seasonal burning. Canadian Journal of Botany. 66:
30. Ford, Mary S. (Jesse). 1990. A 10,000-yr history of natural ecosystem
acidification. Ecological Monographs. 60(1): 57-89. 
31. Frolik, A. L. 1941. Vegetation on the peat lands of Dane County,
Wisconsin. Ecological Monographs. 11(1): 117-140. 
32. Garrison, George A.; Bjugstad, Ardell J.; Duncan, Don A.; [and others].
1977. Vegetation and environmental features of forest and range
ecosystems. Agric. Handb. 475. Washington, DC: U.S. Department of
Agriculture, Forest Service. 68 p. 
33. Gates, Frank C. 1942. The bogs of northern lower Michigan. Ecological
Monographs. 12(3): 213-254. 
34. Glaser, Paul H. 1992. Raised bogs in eastern North America--regional
controls for species richness and floristic assemblages. Journal of
Ecology. 80(3): 535-554. 
35. Glaser, Paul H.; Janssens, Jan A.; Siegel, Donald I. 1990. The response
of vegetation to chemical and hydrological gradients in the Lost River
peatland, northern Minnesota. Journal of Ecology. 78: 1021-1048.
36. Gleason, Henry A.; Cronquist, Arthur. 1991. Manual of vascular plants of
northeastern United States and adjacent Canada. 2nd ed. New York: New
York Botanical Garden. 910 p. 
37. Heinselman, M. L. 1959. Natural regeneration of swamp black spruce in
Minnesota under various cutting systems. Production Res. Rep. No. 32.
Washington, DC: U.S. Department of Agriculture, Forest Service. 22 p.
38. Heinselman, M. L. 1970. Landscape evolution, peatland types and the
environment in the Lake Agassiz Peatlands Natural Area, Minnesota.
Ecological Monographs. 40(2): 235-261. 
39. Hogg, Edward H.; Wein, Ross W. 1988. The contribution of Typha
components to floating mat buoyancy. Ecology. 69(4): 1025-1031. 
40. Humrickhouse, A. Bruce. 1986. Aerial ignition for prescribed burning in
Minnesota. In: Koonce, Andrea L., ed. Prescribed burning in the Midwest:
state-of-the-art: Proceedings of a symposium; 1986 March 3-6; Stevens
Point, WI. Stevens Point, WI: University of Wisconsin, College of
Natural Resources, Fire Science Center: 138-145. 
41. Jeglum, J. K. 1975. Classification of swamp for forestry problems. In:
Fraser, J. W.; Jeglum, J. K.; Ketcheson, D. E.; Robinson, F. C.; Van
Bers, H. P. G.; McLain, K. M.; Auld, J. M., technical coordinators.
Black Spruce Symposium; 1975 September 23-25; Thunder Bay, ON. Symposium
Proceedings 0-P-4. Sault Ste. Marie, ON: Department of the Environment,
Canadian Forestry Service, Great Lakes Forest Research Centre: 227-241.
42. Johnston, William F. 1977. Manager's handbook for black spruce in the
North Central States. Gen. Tech. Rep. NC-34. St. Paul, MN: U.S.
Department of Agriculture, Forest Service, North Central Forest
Experiment Station. 18 p. 
43. Jones, R. Keith; Pierpoint, Geoffrey; Wickware, Gregory M.; [and
others]. 1983. Field guide to forest ecosystem classification for the
Clay Belt, site region 3e. Maple, Ontario: Ministry of Natural
Resources, Ontario Forest Research Institute. 160 p. 
44. Kartesz, John T.; Kartesz, Rosemarie. 1980. A synonymized checklist of
the vascular flora of the United States, Canada, and Greenland. Volume
II: The biota of North America. Chapel Hill, NC: The University of North
Carolina Press; in confederation with Anne H. Lindsey and C. Richie
Bell, North Carolina Botanical Garden. 500 p. 
45. Kelsall, John P. 1957. Continued barren-ground caribou studies. Wildlife
Management Bulletin Series 1: No. 12. Ottawa, Canada: Department of
Northern Affairs and National Resources, National Parks Branch, Canadian
Wildlife Service. 148 p. 
46. Kuchler, A. W. 1964. Manual to accompany the map of potential vegetation
of the conterminous United States. Special Publication No. 36. New York:
American Geographical Society. 77 p. 
47. Kudish, Michael. 1992. Adirondack upland flora: an ecological
perspective. Saranac, NY: The Chauncy Press. 320 p. 
48. Kurmis, Vilis; Webb, Sara L.; Merriam, Lawrence C., Jr. 1986. Plant
communities of Voyageurs National Park, Minnesota, U.S.A. Canadian
Journal of Botany. 64: 531-540. 
49. Larsen, James A. 1971. Vegetational relationships with air mass
frequencies: boreal forest and tundra. Arctic. 24: 177-194. 
50. LeBlanc, Cheryl M.; Leopold, Donald J. 1992. Demography and age
structure of a central New York shrub-carr 94 years after fire. Bulletin
of the Torrey Botanical Club. 119(1): 50-64. 
51. LeResche, Robert E.; Davis, James L. 1973. Importance of nonbrowse foods
to moose on the Kenai Peninsula, Alaska. Journal of Wildlife Management.
37(3): 279-287. 
52. Little, S. 1964. Fire ecology and forest management in the New Jersey
pine region. In: Proceedings, 3rd annual Tall Timbers fire ecology
conference; 1964 April 9-10; Tallahassee, FL. No. 3. Tallahassee, FL:
Tall Timbers Research Station: 35-59. 
53. Little, Silas. 1974. Effects of fire on temperate forests: northeastern
United States. In: Kozlowski, T. T.; Ahlgren, C. E., eds. Fire and
ecosystems. New York: Academic Press: 225-250. 
54. Little, Silas; Moorhead, George R.; Somes, Horace A. 1958. Forestry and
deer in the Pine Region of New Jersey. Station Pap. No. 109. Upper
Darby, PA: U.S. Department of Agriculture, Forest Service, Northeastern
Forest Experiment Station. 33 p. 
55. Laderman, Aimlee D.; Golet, Francis C.; Sorrie, Bruce A.; Woolsey, Henry
L. 1987. Atlantic white cedar in the glaciated Northeast. In: Laderman,
Aimlee D., ed. Atlantic white cedar wetlands. [Place of publication
unknown]: Westview Press: 19-34. 
56. Loope, Walter L. 1991. Interrelationships of fire history, land use
history, and landscape pattern within Pictured Rocks National Seashore,
Michigan. Canadian Field-Naturalist. 105(1): 18-28. 
57. Magnus, Lester T. 1949. Cover type use of the ruffed grouse in relation
to forest management on the Cloquet Forest Experiment Station. Flicker.
21(2): 29-44. 
58. Maikawa, E.; Kershaw, K. A. 1976. Studies on lichen-dominated systems.
XIX. The postfire recovery sequence of black spruce-lichen woodland in
the Abitau Lake region, N.W.T. Canadian Journal of Botany. 54:
59. Maini, J. S. 1966. Pytoecological study of sylvotundra at Small Tree
Lake, N.W.T. Arctic. 19: 220-243. 
60. Martin, Alex C.; Erickson, Ray C.; Steenis, John H. 1957. Improving duck
marshes by weed control. Circular 19 (Revised). Washington, DC: U.S.
Department of the Interior, Bureau of Sport Fisheries and Wildlife. 60
61. Miller, Donald R. 1976. Taiga winter range relationships and diet.
Canadian Wildlife Service Rep. Series No. 36. Ottawa, ON: Environment
Canada, Wildlife Service. 42 p. (Biology of the Kaminuriak population of
barren-ground caribou; pt 3). 
62. Motzkin, Glenn H.; Patterson, William A., III. 1991. Vegetation patterns
and basin morphometry of a New England moat bog. Rhodora. 93(876):
63. Pearce, C. M.; McLennan, D.; Cordes, L. D. 1988. The evolution and
maintenance of white spruce woodlands on the Mackenzie Delta, N. W. T.,
Canada. Holarctic Ecology. 11(4): 248-258. 
64. Raunkiaer, C. 1934. The life forms of plants and statistical plant
geography. Oxford: Clarendon Press. 632 p. 
65. Reader, R. J. 1977. Bog ericad flowers: self-compatibility and relative
attractiveness to bees. Canadian Journal of Botany. 55(17): 2279-2287.
66. Santelmann, Mary V. 1991. Influences on the distribution of Carex
exilis: an experimental approach. Ecology. 72(6): 2025-2037. 
67. Schaefer, James A.; Pruitt, William O., Jr. 1991. Fire and woodland
caribou in southeastern Manitoba. Wildlife Monograph No. 116.
Washington, DC: The Wildlife Society, Inc. 39 p. 
68. Schmidt, F. J. W. 1936. Winter food of the sharp-tailed grouse and
pinnated grouse in Wisconsin. Wilson Bulletin. September: 186-203.
69. Scotter, George W. 1967. The winter diet of barren-ground caribou in
northern Canada. Canadian Field-Naturalist. 81: 33-39. 
70. Seymour, Frank Conkling. 1982. The flora of New England. 2d ed.
Phytologia Memoirs 5. Plainfield, NJ: Harold N. Moldenke and Alma L.
Moldenke. 611 p. 
71. Sims, R. A.; Stewart, J. M. 1981. Aerial biomass distribution in an
undisturbed and disturbed subarctic bog. Canadian Journal of Botany. 59:
72. Sirois, Luc; Payette, Serge. 1989. Postfire black spruce establishment
in subarctic and boreal Quebec. Canadian Journal of Forestry Research.
19: 1571-1580. 
73. Stallard, Harvey. 1929. Secondary succession in the climax forest
formations of northern Minnesota. Ecology. 10(4): 476-547. 
74. Stickney, Peter F. 1989. Seral origin of species originating in northern
Rocky Mountain forests. Unpublished draft on file at: U.S. Department of
Agriculture, Forest Service, Intermountain Research Station, Fire
Sciences Laboratory, Missoula, MT; RWU 4403 files. 7 p. 
75. Stone, W. 1973. The plants of southern New Jersey. Boston, MA: Quarterman
Publications, Inc. 892 p. 
76. Strang, R. M. 1971. The ecology of the rocky heathlands of western Nova
Scotia. In: Proceedings, annual Tall Timbers fire ecology conference;
1970 August 20-21; Fredericton, NB. No. 10. Tallahassee, FL: Tall
Timbers Research Station: 287-292. 
77. Taft, John B.; Solecki, Mary Kay. 1990. Vascular flora of the wetland
and prairie communities of Gavin Bog and Prairie Nature Preserve, Lake
County, Illinois. Rhodora. 92(871): 142-165. 
78. Telfer, E. S. 1972. Understory biomass in five forest types in
southwestern Nova Scotia. Canadian Journal of Botany. 50: 1263-1267.
79. U.S. Department of Agriculture, Soil Conservation Service. 1982.
National list of scientific plant names. Vol. 1. List of plant names.
SCS-TP-159. Washington, DC. 416 p. 
80. Viereck, Leslie A. 1982. Effects of fire and firelines on active layer
thickness and soil temperatures in interior Alaska. In: Proceedings, 4th
Canadian permafrost conference; 1981 March 2-6; Calgary, AB. The Roger
J.E. Brown Memorial Volume. Ottawa, ON: National Research Council of
Canada: 123-135. 
81. Vogl, Richard J. 1964. The effects of fire on a muskeg in northern
Wisconsin. Journal of Wildlife Management. 28(2): 317-329. 
82. Wilcox, Douglas A.; Ray, Gary. 1989. Using "living mat" transplants to
restore a salt-impacted bog (Indiana). Restoration and Management Notes.
7(1): 39. 
83. Zoltai, S. C.; Tarnocai, C. 1971. Properties of a wooded palsa in
northern Manitoba. Arctic and Alpine Research. 3(2): 115-129.