Lesser Spikemoss

Selaginella densa has been treated as including three varieties: var. densa , var. scopulorum (Maxon) R. M. Tryon, and var. standleyi (Maxon) R. M. Tryon (R. M. Tryon 1955), which are recognized here at the species level. Intermediates between S . densa and the other two species of the group may represent ecological variations of the species, hybrids between species within the complex, or hybrids with other closely related species, such as S . watsonii . This group is in need of detailed systematic studies. Megasporangia with only two well-developed megaspores have been observed, which may indicate apogamy and the presence of different races as found in S . rupestris .

Plants terrestrial or on rock, forming cushionlike or loose mats. Stems decumbent or creeping, not readily fragmenting, irregularly forked, without budlike arrested branches, tips straight; main stem upperside and underside structurally slightly different, conspicuously indeterminate, lateral branches radially symmetric, conspicuously or inconspicuously determinate, strongly ascending, 2--3-forked. Rhizophores borne on upperside of stems, throughout stem length, 0.2--0.35 mm diam. Leaves essentially monomorphic, in poorly defined pseudowhorls of 5 or 6, tightly appressed, ascending, green, linear to linear-lanceolate, (2.7--)3--5 X 0.4--0.7 mm (upperside leaves smaller than underside ones, also smaller on ascending buds); abaxial ridges present; base long-decurrent, oblique, and glabrous on underside leaves, slightly decurrent, oblique, and sometimes pubescent on upperside leaves; margins long-ciliate, cilia transparent, mostly ascending or spreading on proximal 1/2, ascending on distal 1/2, 0.07--0.17(--0.2) mm; apex slightly keeled to plane, rather obtuse, abruptly long-bristled; bristle white or transparent, puberulent, (1--)1.25--1.9 mm. Strobili solitary, (0.5--)1--3(--4) cm; sporophylls ovate-lanceolate, seldom ovate, abaxial ridges well defined, base glabrous, margins ciliate entire length or dentate near tip, apex usually long-bristled.

Alta., B.C., Man., Ont., Sask.; Ariz., Colo., Idaho, Mont., Nebr., N.Mex., N.Dak., S.Dak., Utah, Wyo.

Prairies, alpine meadows, dry rocky slopes, rock crevices, sandstone, quartzite or granite rock, and dry gravelly, clayey or sandy soil; 1100--4000m.

Selaginella rupestris (Linnaeus) Spring var. densa (Rydberg) Clute

lesser spikemoss
little clubmoss
little spikemoss
prairie spikemoss
Rocky Mountain selaginella
spikemoss

More info for the term: cover

Lesser spikemoss provides poor cover for small animals [16].

More info for the term: herb

Description: Lesser 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]. Lesser 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: Lesser 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.

The range of lesser 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]. Distribution of lesser spikemoss. Map courtesy of USDA, NRCS. 2018. The PLANTS Database. National Plant Data Team, Greensboro, NC [56] [2018, April 4]. The distributions of the varieties of lesser spikemoss are as follows [13,26,27,42]: Selaginella densa. 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. Selaginella densa 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. Selaginella densa var. standleyi is uncommon and found only above timberline in the northern Rocky Mountains.

More info for the terms: fire regime, litter

Lesser spikemoss would appear to have lesser 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]. 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".

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More info for the term: chamaephyte

Chamaephyte

More info for the terms: basal area, cover, forest, frequency, grassland, herb, organic soils, shrubs, tundra

Lesser 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. Lesser spikemoss is an extremely stress-tolerant species and can survive in cold alpine regions with a short growing season, drought, and summer frosts [62]. Lesser 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]. Lesser 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 lesser 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 lesser spikemoss in the aspen grove and grassland community decreases to the north in Saskatchewan [11]. Grassland Sites: Lesser 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, lesser 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, lesser 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, lesser 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, lesser 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, lesser 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, lesser 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 lesser spikemoss (var. scopulorum) grows on open rocky sites in red fir (Abies magnifica) and lodgepole pine forests of Siskiyou County [42]. Parent material: Lesser 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, lesser 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: Lesser 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) lesser spikemoss is found in areas with shallower, rockier, and less sandy soils than areas without lesser spikemoss [57]. Optimum soil depth for lesser spikemoss (var. densa) is between 10 and 20 inches (25.4-50.8 cm) [16]. Growth of lesser 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

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This species is known to occur in association with the following cover types (as classified by the Society of American Foresters):

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

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This species is known to occur in the following ecosystem types (as named by the U.S. Forest Service in their Forest and Range Ecosystem [FRES] Type classification):

More info for the term: shrub

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

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This species is known to occur in association with the following plant community types (as classified by Küchler 1964):

More info for the terms: forest, woodland

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

Lesser spikemoss is killed by fire except where it is protected by site conditions [51].

Lesser 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 lesser spikemoss [57]. Bighorn sheep may eat some spikemoss (Selaginella spp.) in New Mexico [40].

More info for the terms: association, climax, forest, grassland, habitat type

In the Great Plains grasslands of southern Canada and the northern
United States, lesser 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, lesser spikemoss is rare outside of the needle-and-thread grass
(Hesperostipa comata)/threadleaf sedge (Carex filifolia) habitat
type where it is an important species [24,25]. Published classification
schemes listing lesser 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

More info for the terms: fern, fern ally

Fern Ally

More info for the terms: basal area, competition, cover, grassland, litter

The role of lesser 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 lesser 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 lesser spikemoss seems to be
confounded by drought. In Canadian and Montana mixed prairie, lesser
spikemoss is able to increase during periods of drought [10,18,58].
Also, lesser spikemoss increases when protected from grazing and
decreases with grazing due to trampling of grazing animals [10]. Lesser
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 lesser 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 lesser 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]. Lesser spikemoss increased under all
levels of grazing, with the greatest increase in the most lightly grazed
area. On ungrazed land lesser spikemoss increased in basal area from 11
percent to 16 percent. Results of a second 10-year study showed the
basal area of lesser 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, lesser
spikemoss increased more under a medium level of grazing than under
severe grazing intensity [9]. Lesser 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. Lesser
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, lesser 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 lesser spikemoss [18]. However, in the northern plains
response depends upon precipitation [54]. There is no evidence that
nitrogen application alone kills lesser spikemoss [52]. When fertilizers
containing nitrogen and phosphorus were added to grassland plots in each
of 2 successive years, the cover of live lesser 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 lesser spikemoss was subordinated to the
more vigorous native grasses and decreased the second season [18].
After more than 30 years with normal weather, lesser 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 lesser spikemoss [66].

Mechanical treatment: Mechanical treatments reduced lesser 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 lesser spikemoss, and combination treatments seemed most
successful. When the treated area was resurveyed over 30 years later,
lesser spikemoss cover was still so decreased that researchers concluded
that lesser spikemoss does not easily reestablish on northern mixed
prairie following mechanical treatment [19]. Lesser 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 lesser
spikemoss while increasing the yield of desirable grasses are AMS
(ammate) and atrazine [59]. Spring treatment is most effective.
Monuron, paraquat, and bromacil control lesser 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.
Their effectiveness is increased with the use of a surfactant
[52].

The energy and protein value of lesser spikemoss forage is poor [16].
Aboveground parts of lesser 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

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

More info for the term: cover

While lesser 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, lesser spikemoss can be transplanted into gardens where it is an attractive ground cover that grows on rocks and in other dry situations [34].

The degree of use shown by livestock and wildlife species for
lesser 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 ---- ----

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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 lesser 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].

More info for the terms: cover, frequency

Generally, spikemosses are lacking following recent fire or other major disturbance [55]. In a study of paired stands in mixed grass prairie in Manitoba, lesser 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 lesser spikemoss was much less following fires that burned from 3 months to 4 years before sampling [17].

secondary colonizer; off-site spores carried to site after year two

More info for the term: natural

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 lesser 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 lesser spikemoss do not have a natural tendency to fragment when dry [55].

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This species can be found in the following regions of the western United States (according to the Bureau of Land Management classification of Physiographic Regions of the western United States):

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

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More info for the term: xeric

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, lesser spikemoss pioneers on the gravel mulch left by rodent disturbance in grassy meadows [29]. Lesser spikemoss (var. scopulorum) is found in alpine areas on unstable soils disturbed by frost and abraded by wind [29].

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

The scientific name of lesser spikemoss is Selaginella densa Rydb.
(Selaginellaceae). There are three varieties of lesser spikemoss [31]:

Selaginella densa var. densa, lesser spikemoss
Selaginella densa var. scopulorum (Maxon) Tryon, Rocky Mountain spikemoss
Selaginella densa var. standleyi (Maxon) Tryon, Standley's spikemoss

Lesser 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].

Selaginella densa is a species of spikemoss known by the common names lesser spikemoss, prairie spikemoss, and Rocky Mountains spikemoss. It is native to western North America, where it can be found from Alaska to Ontario, the Dakotas, Texas and far northern California.

It grows in many types of habitat, from grassland to the alpine climates of high mountains, in rocky and sandy areas. It is a dominant plant in many types of prairie on the Great Plains, especially shortgrass prairie, where it grows alongside dominant grasses. It grows in windy, exposed, snow-free rock outcrops on mountain peaks in several ranges, including the Cascade Range and the Front Range of the Rocky Mountains. It is most common on dry soils in open areas, tolerating desiccation relatively easily.

This lycophyte forms mats or cushions of creeping stems which fork into small, upright branches. The green, linear or lance-shaped leaves are up to 5 millimeters long including the short, soft bristles on the tips. They are flattened to the stem. The strobili at the ends of the stems can be up to 3 or 4 centimeters long.

This compact groundcover plant protects the soil from erosion and can be used in landscaping for that purpose.