SPECIES: Selaginella densa

• Introductory
• Distribution and occurrence
• Management Considerations
• Botanical and ecological characteristics
• Fire ecology
• Fire effects
• References

Introductory
SPECIES: Selaginella densa



AUTHORSHIP AND CITATION : 
Crane, M. F. 1990. Selaginella densa. 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/ [].




ABBREVIATION : 
SELDEN

SYNONYMS : 
   Selaginella rubestris var. densa
   Selaginella scopulorum
   Selaginella engelmannii
   Selaginella engelmannii var scopulorum
   Selaginella engelmannii var standleyi
   Selaginella standleyi


SCS PLANT CODE : 
   SEDE2
   SEDES
   SEDES2


COMMON NAMES : 
   little spikemoss
   spikemoss
   Rocky Mountain selaginella
   prairie spikemoss
   little clubmoss


TAXONOMY : 
The currently accepted scientific name of little spikemoss is Selaginella
densa Rydb. [31].  There are three varieties of little spikemoss [31]:
    S. d. var. densa
    S. d. var. scopulorum (Maxon) Tryon
    S. d. var. standleyi (Maxon) Tryon


LIFE FORM : 
Fern or Fern Ally

FEDERAL LEGAL STATUS : 
No special status

OTHER STATUS : 
NO-ENTRY

DISTRIBUTION AND OCCURRENCE
SPECIES: Selaginella densa



GENERAL DISTRIBUTION : 
The range of little spikemoss extends south from the Alaska panhandle to
northwest California and east into Manitoba and the Dakotas.  It is
common on the Great Plains and in the Rocky Mountains it grows as far
south as eastern Utah and Arizona, New Mexico and Trans-Pecos Texas
[13,27].  The distributions of the varieties of little spikemoss are as
follows [13,26,27,42]:

    S. d. var. densa is the characteristic variety found on the northern Great Plains.  It may occasionally extend into western Montana, southwest
Alberta and southeast British Columbia.  Further south it is found in
the mountains of Colorado and the LaSal Mountains of Utah.

    S. d. var. scopulorum is the common  variety in the mountains of the
Northern Rocky Mountain Region through the LaSal and Uinta mountains of
eastern Utah to west Texas.  It is also found from British Columbia to
northern California.  It is less common in the mountains of Colorado.

    S. d. var. standleyi is uncommon and found only above timberline in the
northern Rocky Mountains.


ECOSYSTEMS : 
   FRES10  White - red - jack pine
   FRES20  Douglas-fir
   FRES21  Ponderosa pine
   FRES23  Fir - spruce
   FRES26  Lodgepole pine
   FRES29  Sagebrush
   FRES30  Desert shrub
   FRES34  Chaparral - mountain shrub
   FRES35  Pinyon - juniper
   FRES36  Mountain grasslands
   FRES38  Plains grasslands
   FRES39  Prairie
   FRES40  Desert grasslands
   FRES44  Alpine


STATES : 
     AZ  CA  CO  KS  MT  NE  NM  ND  OK  OR
     SD  UT  WA  WY  AB  BC  MB  SK



BLM PHYSIOGRAPHIC REGIONS : 
    1  Northern Pacific Border
    2  Cascade Mountains
    4  Sierra Mountains
    5  Columbia Plateau
    8  Northern Rocky Mountains
    9  Middle Rocky Mountains
   10  Wyoming Basin
   11  Southern Rocky Mountains
   12  Colorado Plateau
   13  Rocky Mountain Piedmont
   14  Great Plains
   15  Black Hills Uplift
   16  Upper Missouri Basin and Broken Lands


KUCHLER PLANT ASSOCIATIONS : 
   K007  Red fir forest
   K008  Lodgepole pine - subalpine forest
   K011  Western ponderosa forest
   K012  Douglas-fir forest
   K015  Western spruce - fir forest
   K016  Eastern ponderosa forest
   K017  Black Hills pine forest
   K018  Pine - Douglas-fir forest
   K019  Arizona pine forest
   K020  Spruce - fir - Douglas-fir forest
   K021  Southwestern spruce - fir forest
   K023  Juniper - pinyon woodland
   K037  Mountain mahogany - oak scrub
   K038  Great Basin sagebrush
   K039  Blackbrush
   K040  Saltbush - greasewood
   K051  Wheatgrass - bluegrass
   K052  Alpine meadows and barren
   K055  Sagebrush steppe
   K056  Wheatgrass - needlegrass shrubsteppe
   K057  Galleta - three-awn shrubsteppe
   K063  Foothills prairie
   K064  Grama - needlegrass - wheatgrass
   K065  Grama - buffalograss
   K066  Wheatgrass - needlegrass
   K067  Wheatgrass - bluestem - needlegrass
   K070  Sandsage - bluestem prairie
   K095  Great Lakes pine forest


SAF COVER TYPES : 
     1  Jack pine
   205  Mountain hemlock
   206  Engelmann spruce - subalpine fir
   207  Red fir
   208  Whitebark pine
   209  Bristlecone pine
   210  Interior Douglas-fir
   218  Lodgepole pine
   219  Limber pine
   220  Rocky Mountain juniper
   237  Interior ponderosa pine
   238  Western juniper
   239  Pinyon - juniper


SRM (RANGELAND) COVER TYPES : 
NO-ENTRY


HABITAT TYPES AND PLANT COMMUNITIES : 
In the Great Plains grasslands of southern Canada and the northern
United States, little spikemoss can be a dominant in three of the five
major grass associations: the short-grass prairie, mixed prairie and
fescue (Festuca scabrella) prairie [7,9].  At higher elevations in
Glacier Park, it codominates with Idaho fescue (F. idahoensis) in a
climax grassland association [48].  In the Custer National Forest of
Montana, North and South Dakota and the Theodore Roosevelt National Park
of North Dakota, little spikemoss is rare outside of the needle and
thread grass (Stipa comata)/threadleaf sedge (Carex filifolia) habitat
type where it is an important species [24,25].  Published classification
schemes listing little spikemoss as an indicator species or a dominant
part of vegetation in plant associations (pas) are presented below:

Area                    Classification        Authority

Region 2: CO,NE,KS,     general veg. pas      Johnston 1987
 SD,WY

MANAGEMENT CONSIDERATIONS
SPECIES: Selaginella densa




IMPORTANCE TO LIVESTOCK AND WILDLIFE : 
Little spikemoss is a minor part of elk diets but is not a valuable elk
browse [36].  During a Montana study domestic animals were never
observed grazing on little spikemoss [57].  Bighorn sheep may eat some
spikemoss (Selaginella spp.) in New Mexico [40].


PALATABILITY : 
The relish and degree of use shown by livestock and wildlife species for
little spikemoss (var. densa) in several western states is rated as
follows [16]:

                        UT      WY      MT      ND    
Cattle                 poor    poor    poor    poor   
Sheep                  poor    poor    poor    poor   
Horses                 poor    poor    poor    poor   
Elk                    fair    poor    poor    ----   
Mule deer              fair    poor    poor    fair   
White-tailed deer      ----    poor    ----    fair   
Antelope               fair    poor    poor    fair   
Upland game birds      fair    fair    ----    poor   
Waterfowl              fair    ----    ----    ----   
Small nongame birds    fair    ----    ----    ----   
Small Mammals          fair    fair    ----    ----   


NUTRITIONAL VALUE : 
The energy and protein value of little spikemoss forage is poor [16].
Aboveground parts of little spikemoss have a high ash content (19.7%).
Most of this is silica which comprises about 16.5 percent of plant dry
weight.  Other results of this analysis are given below [59]:

              Percent of dry weight of aboveground portions of plant
Calcium       0.20
Potassium     0.30
Iron          0.038
Zinc          0.023
Sodium        0.29
Phosphorus    0.11
Protein       8.50


COVER VALUE : 
Little spikemoss provides poor cover for small animals [16].


VALUE FOR REHABILITATION OF DISTURBED SITES : 
Little spikemoss has poor short-term or long-term revegetation potential
[16].  It does grow well on gentle and moderate slopes and it has low to
moderate erosion control potential.  However, its potential biomass
production is low and establishment requirements may be exacting [16].


OTHER USES AND VALUES : 
While little spikemoss does not provide forage, it does protect the soil
from erosion by wind or water and reduces the effects of tramping [7].
With care, little spikemoss can be transplanted into gardens where it is
an attractive ground cover that grows on rocks and in other dry
situations [34].


OTHER MANAGEMENT CONSIDERATIONS : 
The role of little spikemoss in mixed prairie is not well understood,
although its influence on other vegetation and the habitat has been
thought to be slight because its requirements for water and nutrients
are low [9,10,60].  During light showers, its dense mats and extensive,
shallow roots may intercept and soak up all the available water [55,57].
During high intensity storms, the mats of little spikemoss act to
increase infiltration and decrease runoff and surface erosion [57].  Its
shallow root system also limits spikemoss growth to periods of the year
when moisture is available at shallow depths [59].

Grazing effects:  The effect of grazing on little spikemoss seems to be
confounded by drought.  In Canadian and Montana mixed prairie, little
spikemoss is able to increase during periods of drought [10,18,58].
Also, little spikemoss increases when protected from grazing and
decreases with grazing due to trampling of grazing animals [10].  Little
spikemoss is relatively weakly rooted and easily damaged by trampling
[37].  Decreases in response to grazing may also be explained by the
exposure and drying of the surface soil when cover is removed by grazing
[18].  In the short-grass prairie of southeastern Alberta and
southwestern Saskatchewan, grasses can easily establish in areas with
high cover of little spikemoss during years with above normal
precipitation, but they are rarely able to establish during dry years
[7].

A 4-year Montana study done during a period of normal rainfall compared
ungrazed mixed prairie with mixed prairie moderately grazed by sheep.
Cover of little spikemoss decreased from 21 to 17.6 percent on the
ungrazed site but it decreased from 15.1 to 7.1 percent on the grazed
area [58].  The strong decrease on grazed prairie was attributed to
trampling, competition, and manure [57].
 
A 7-year study of three levels of grazing intensity on the short-grass
prairie in southeastern Alberta and southwestern Saskatchewan was done
during dry and drought years [9].  Little spikemoss increased under all
levels of grazing, with the greatest increase in the most lightly grazed
area.  On ungrazed land little spikemoss increased in basal area from 11
percent to 16 percent.  Results of a second 10-year study showed the
basal area of little spikemoss increased by 37 percent on ungrazed and 27
percent on grazed land, while grass cover generally decreased.  Looking
at total vegetation cover the authors concluded that "climate rather
than moderate grazing use was the principal factor affecting plant
cover" between 1928 and 1939.  During a third 5-year study, little
spikemoss increased more under a medium level of grazing than under
severe grazing intensity [9].  Little spikemoss increases more under
rotational grazing than under continuous grazing [9,65].

A 3-year North Dakota mixed prairie study compared exclosures
established 38 to 41 years previously with cattle-grazed range.  Little
spikemoss cover did not vary significantly despite major differences in
species composition of grasses and silver sagebrush (Artemisia cana)
[5,6].  Site differences were more important than grazing pressure [6].
Ross and Hunter [50] list spikemoss as increasing under grazing pressure
in Montana.  However, little spikemoss increases very slowly when taller,
competing vegetation is partly or wholly removed [52].

Treatment with fertilizer:  The primary effect of manure or fertilizer
applications is to increase the competitiveness of taller grasses, thus
decreasing little spikemoss [18].  However, in the northern plains
response depends upon precipitation [54].  There is no evidence that
nitrogen application alone kills little spikemoss [52].  When fertilizers
containing nitrogen and phosphorus were added to grassland plots in each
of 2 successive years, the cover of live little spikemoss decreased
significantly.  It was not determined whether this was due to the
nutrients themselves or because of increased competition from other
vegetation [57].  Manuring alone increased all plant cover the first
season of a Montana study, but little spikemoss was subordinated to the
more vigorous native grasses and decreased the second season [18].
After more than 30 years with normal weather, little spikemoss was still
reduced in plots treated by annual applications of manure for 1 to 11
years [19].  Mulching, with or without added fertilizer, can nearly
eliminate little spikemoss [66].

Mechanical treatment:  Mechanical treatments reduced little spikemoss
cover between 25 and 70 percent in northern Montana mixed prairie [52].
The effects of various combinations of manure treatment, disking, and
harrowing over a 10-year period along with seeding of crested wheatgrass
(Agropyron cristatum) and yellow sweetclover (Melilotus officinalis)
have been studied [18,19].  Most treatments resulted in long-term
decreases in little spikemoss, and combination treatments seemed most
successful.  When the treated area was resurveyed over 30 years later,
little spikemoss cover was still so decreased that researchers concluded
that little spikemoss does not easily reestablish on northern mixed
prairie following mechanical treatment [19].  Little spikemoss cover and
the cover of either other vegetation or litter were significantly and
negatively correlated [19].

Chemical control:  The most effective chemicals for control of little
spikemoss while increasing the yield of desirable grasses are AMS
(ammate) and atrazine [59].  Spring treatment is most effective.
Monuron, paraquat, and bromacil control little spikemoss but also reduce
the yield of or kill other vegetation [59].  Further range tests
indicate that ammate, atrazine, and monuron are the best treatments
[52].  Their effectiveness is increased with the use of a surfactant
[52].

BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Selaginella densa



GENERAL BOTANICAL CHARACTERISTICS : 
Description:  Little spikemoss is an evergreen, nonflowering herb that
forms dense, cushionlike mats which are seldom more than 1 inch (2.5 cm)
in height [10,57].  The short, leafy, compactly branched stems lie along
the soil surface and may be 4 inches (1 dm) across [27].  The simple,
awn-tipped leaves are very small, up to about 0.1 inch (2.5 mm) long and
0.02 inch (0.5 mm) wide, and arranged in a relatively dense spiral along
the stem.  There is usually a single, unbranched vein.  The leaves
underneath the stem are longer than leaves on top along the same part of
the stem [42].  Little spikemoss has true roots which are very fine
(0.008 inch or 0.2 mm in diameter) and minutely branched.  They form a
tangled mass and may comprise 86 percent of the plant dry matter [59].
Most roots occur within 0.78 to 2.0 inches (2-5 cm) of the soil surface
[12].

Drought Resistance:  Little spikemoss is very resistant to drought if the
roots are not disturbed.  In the laboratory, clumps allowed to desiccate
for 6 and 33 months were then revived simply by watering and later
planting [55,61].  The clump that was revived after 33 months developed
reproductive cones within 3 months [61].  When all soil was removed from
roots, no plants survived after 5 weeks of air drying [59].  Shoots that
are dormant during drought have their leaves closely appressed to the
stem and are a dull grayish-green instead of the ash-gray of dead shoots
[61].  Young plants are equally drought resistant.  On a site near
Saskatoon, Saskatchewan, Webster and Steeves [61] found over 50
locations where sporelings had survived periods of drought.


RAUNKIAER LIFE FORM : 
   Undisturbed State:  Chamaephyte
   Burned or Clipped State:  Chamaephyte


REGENERATION PROCESSES : 
The spikemoss life cycle differs from that of flowering plants.  At
branch ends, four-angled "cones" or strobili are formed.  Each has two
types of spore-bearing structures, microsporangia and megasporangia, in
the leaf axils, with megasporangia located below the microsporangia
[61].  Microspores are released passively to fall through the strobili
to the ground [32].  At maturity they will release microscopic,
flagellated sperm cells.  The sperm require water to swim to the egg cell
which develops from cells of the megasporangia.  Where fertilization
occurs is not known [52].  Tissue surrounding the fertilized egg may
carry on photosynthesis as well as provide stored food for the
developing embryo.  This entire structure may be shed or held in the
leaf axils of the strobili while the embryo develops.  The necessity of
water for sexual reproduction restricts the habitat of spikemosses [15],
and young plants are not often reported [18,52].

As little spikemoss clumps grow the centers die, leaving a ring of live
material surrounding a dead core [59].  Under range conditions lateral
growth was observed to be less than 0.4 inch (1 cm) a year, making
vegetative spreading a slow process [18,59].  During another field study
growth of less than 0.2 inch (5 mm) in 5 seasons was observed [52].
Fragmentation might be another means of vegetative reproduction and
dispersal [18], although stems of little spikemoss do not have a natural
tendency to fragment when dry [55].


SITE CHARACTERISTICS : 
Little spikemoss is most often found on dry shallow soils that are
gravelly or rocky or have gravelly or stony subsoils [57].  It is most
common in grasslands, alpine tundra, and high subalpine communities
which occupy dry, snow-free ridges.  Little spikemoss is an extremely
stress-tolerant species and can survive in cold alpine regions with a
short growing season, drought, and summer frosts [62].  Little spikemoss
is not common in forests but can be found in Douglas-fir (Pseudotsuga
menziesii) with ponderosa pine (Pinus ponderosa) or lodgepole pine (P.
contorta), Engelmann spruce (Picea engelmannii) and subalpine fir (Abies
lasiocarpa), or aspen (Populus tremuloides) communities [33,44].  Little
spikemoss also grows in pinyon (Pinus edulis)-juniper (Juniperus spp.),
sagebrush (Artemisia spp.), and krummholz communities [63].  In Jackson
Hole, Wyoming the big sagebrush (A. tridentata) community has abundant
little spikemoss [47].  In northern Montana aspen grove and grassland
communities, it is found primarily with Hood's phlox (Phlox hoodii) on
stony moraine summits, outwash fans and coarse gravels [38].  The
abundance of little spikemoss in the aspen grove and grassland community
decreases to the north in Saskatchewan [11].

Grassland Sites:  Little spikemoss is most abundant in short-grass
prairie.  Its basal area may be equal to that of all other herbs and
shrubs [7,9].  In mixed prairie, little spikemoss is slightly less
abundant, occurring with an overall frequency of 74 to 98 percent and
cover up to 25 percent [10].  It has much less cover and is not evenly
distributed in the fescue prairie [7,11].  In the northern Red River
Valley, it dominates with needle-and-thread grass [45].  On sites with
standing surface water, little spikemoss will be unimportant [64].
However, in Montana, areas where it grows are closer to permanent water
than areas where it does not grow [57].  In North Dakota, little
spikemoss is common on a variety of grassland habitat types except those
with extra moisture [64].

Alpine and subalpine sites:  In the Washington and British Columbia
Cascades, little spikemoss is common in herb field, the Bellard
alpinesedge (Kobresia myosuroides), and purple reedgrass (Calamagrostis
purpurascens) communities on sites that are essentially snow-free during
the winter.  On such sites it is exposed to high wind, low temperatures,
and frequent frosts all winter [20].  On alpine sites in Montana, little
spikemoss does well where Hooker mountainavens (Dryas octopetala) is
dominant [2].  In alpine areas in Utah, it grows in cushion plant
communities with alpine avens (Geum rossii) and on dry meadows and
alpine turf [37].  On the Colorado Front Range, little spikemoss is part
of several forest communities, but its greatest abundance is at higher
elevations in Bellard alpinesedge meadows or under limber pine (Pinus
flexilis) on exposed rocky sites [33,44].  It is well adapted to these
and other alpine cushion-plant communities [62].  In contrast, near
Schoolroom Glacier in the Teton Range of Wyoming, it is found in a
meadow community with kentrophyta milkvetch (Astragalus kentrophyta)
[53].  In Alberta it grows under limber pine on the rocky, dry slopes
and summits of exposed ridges [41].  In northern California little
spikemoss (var. scopulorum) grows on open rocky sites in red fir (Abies
magnifica) and lodgepole pine forests of Siskiyou County [42].

Parent material:  Little spikemoss grows in the drier interior of British
Columbia except for a disjunct population on dry, well-aerated and warm
limestone soils on the Queen Charlotte Islands [49].  In Montana, little
spikemoss does well on sites with thin, rocky, and unstable soils derived
from calcareous parent material [2].  In the Bighorn Mountains of
Wyoming, it is present on granitic soils but almost absent on soils
derived from sedimentary rock [57].

Soil texture:  Little spikemoss is common on medium texture soils and
sandy loams.  It is less common on sandy soils and rare on clay
[10,52,57].  In grasslands dominated by bluebunch wheatgrass
(Pseudoroegneria spicata) little spikemoss is found in areas with
shallower, rockier, and less sandy soils than areas without little
spikemoss [57].  Optimum soil depth for little spikemoss (var. densa) is
between 10 and 20 inches (25.4-50.8 cm) [16].  Growth of little spikemoss
(var. densa) on various soils in several western states is ranked as
follows [16]:

                      UT       WY       MT       ND
Soil texture
  Gravel             good     fair     fair     fair
  Sand               good     poor     fair     fair
  Sandy loam         good     good     fair     fair
  Loam               good     good     good     good
  Clay loam          good     good     good     good
  clay               fair     fair     fair     good
  dense clay         poor     poor     poor     poor
Organic soils        fair     poor     poor     ----
Acidic soils         fair     poor     poor     ----
Saline soils         fair     poor     poor     poor
Sodic soils          ----     poor     poor     fair
Sodic-saline soils   poor     poor     poor     poor

Elevation:  Elevational ranges in some western regions are
[16,26,30,42,63]:

                     Minimum                   Maximum
                    feet     meters          feet     meters

Arizona            11,470    3,496         11,470     3,496
California
 var. scopulorum    5,000    1,524          7,000     2,134
Colorado
 var. densa         4,000    1,219         12,000     3,658
 var. scopulorum    8,000    2,438         12,500     3,810
 var. standleyi     9,500    2,896         13,000     3,962
Montana            
 var. scopulorum    6,300    1,920          6,300     1,920
Utah                8,858    2,700         14,107     4,300
Wyoming
 var. densa         6,000    1,829         10,800     3,292
 var. scopulorum    5,600    1,707         10,800     3,292
 var. standleyi     5,600    1,707         10,800     3,292


SUCCESSIONAL STATUS : 
In general, spikemosses (Selaginella spp.) are unable to compete with
other plants in relatively moist habitats [55].  They also are not
important pioneers.  Instead spikemosses are found on open, xeric sites
supporting particular plant communities but shift locally within those
communities.  On such open sites their ability to withstand desiccation
allows them to survive and grow well [55].  On alpine sites of Montana's
Beartooth Plateau, little spikemoss pioneers on the gravel mulch left by
rodent disturbance in grassy meadows [29].  Little spikemoss (var.
scopulorum) is found in alpine areas on unstable soils disturbed by
frost and abraded by wind [29].


SEASONAL DEVELOPMENT : 
In North Dakota spore production begins in June and finishes in July
[16].  In Canadian mixed prairie, vegetative growth begins in early
April, strobili first appear late in April, and spores mature late in
May [10].  In the Colorado alpine, leaves of little spikemoss remain
green all winter when protected from wind but turn brown and erode where
exposed [3].  The cones (strobili) change from green to brown in late
May or early June when they are released from snow [3].  

FIRE ECOLOGY
SPECIES: Selaginella densa



FIRE ECOLOGY OR ADAPTATIONS : 
Little spikemoss would appear to have little defense against fire.
However, it has been observed to survive on dry rocky hillsides where
other vegetation and litter were sparse.  On nearby moist areas where
prefire vegetation was more dense, it was completely removed [51].


POSTFIRE REGENERATION STRATEGY : 
   secondary colonizer; off-site spores carried to site after year two

FIRE EFFECTS
SPECIES: Selaginella densa



IMMEDIATE FIRE EFFECT ON PLANT : 
Little spikemoss is killed by fire except where it is protected by site
conditions [51].


DISCUSSION AND QUALIFICATION OF FIRE EFFECT : 
NO-ENTRY


PLANT RESPONSE TO FIRE : 
Generally, spikemosses are lacking following recent fire or other major
disturbance [55].  In a study of paired stands in mixed grass prairie in
Manitoba, little spikemoss cover was 14.9 percent in a control plot, 6.2
percent following a single fire and 2.3 percent following two fires
[67].  In paired stands in western North Dakota, the frequency of
little spikemoss was much less following fires that burned from 3 months
to 4 years before sampling [17].


DISCUSSION AND QUALIFICATION OF PLANT RESPONSE : 
NO-ENTRY


FIRE MANAGEMENT CONSIDERATIONS : 
Prescribed fire can be used to reduce the cover of little spikemoss.  Any
method of reducing little spikemoss would be most successful if done
during a cycle of wet years on the mixed prairie, as drought would
severely set back the recovery of desirable vegetation [1].

Selaginella densa: References

1. Bailey, Arthur W. 1978. Effects of fire on the mixed prairie vegetation. In: Proceedings: Prairie prescribed burning symposium and workshop; 1978 April 25-28; Jamestown, ND. [Place of publication unknown]: [Publisher unknown]: [5 pages]. On file with: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory, Missoula, MT. [3598]

2. Bamberg, Samuel A.; Major, Jack. 1968. Ecology of the vegetation and soils associated with calcareous parent materials in three alpine regions of Montana. Ecological Monographs. 38(2): 127-167. [12554]

3. Bell, Katherine L. 1974. Autumn, winter and spring phenology of some Colorado alpine plants. The American Midland Naturalist. 91(2): 460-464. [233]

4. Bernard, Stephen R.; Brown, Kenneth F. 1977. Distribution of mammals, reptiles, and amphibians by BLM physiographic regions and A.W. Kuchler's associations for the eleven western states. Tech. Note 301. Denver, CO: U.S. Department of the Interior, Bureau of Land Management. 169 p. [434]

5. Brand, M. D.; Goetz, H. 1978. Secondary succession of a mixed grass community in southwestern North Dakota. Annual Proceedings of the North Dakota Academy of Science. 32(2): 67-78. [7512]

6. Brand, Michael D.; Goetz, Harold. 1986. Vegetation of exclosures in southwestern North Dakota. Journal of Range Management. 39(5): 434-437. [507]

7. Campbell, J. B.; Lodge, R. W.; Johnston, A.; Smoliak, S. 1962. Range management of grasslands and adjacent parklands in the prairie provinces. Publ. 1133. Ottawa, ON: Canada Department of Agriculture, Research Branch. 32 p. [595]

8. Carroll, S. B.; Bliss, L. C. 1982. Jack pine - lichen woodland on sandy soils in northern Saskatchewan and northeastern Alberta. Canadian Journal of Botany. 60: 2270-2282. [7283]

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