North American boreal and western temperate forest vegetation

Salvador Rivas-Martínez, Daniel Sánchez-Mata & Manuel Costa

Itinera Geobotanica 12:5-316 (1999)


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Description of Plant Communities: Tsugo mertensianae-Abietetum procerae

9d. Empetro hermaphroditi-Abietetum bifoliae associatio nova hoc loco

[Abieti bifoliae-Piceetum engelmannii Peinado, Aguirre & Cruz 1998 in Plant Ecology 137: 193. Type relevé l.c., tb. 19, no. 480 (art. 37)]

Climactical Rocky Mountain subalpine fir (Abies bifolia) and Engelmann spruce (Picea engelmannii var. engelmannii) micro- and mesoforests spreading into Continental Temperate (subcontinental) territories; upper orotemperate; lower humid. These forest communities are distributed throughout the Canadian Rockies Subsector areas between the tree line and two or three hundred meters below the timberline and grow on gleyic, gelic or histic podzols. The dynamic succesional pattern of these forests shows a replacement, depending of the ombrotype and the winter snow deepness, by the regional orotemperate climactical forests: Piceetum engelmannio-albertianae or Menziesio ferruginae-Abietetum bifoliae associations.

Bioclimatic diagnosis: Ic 23-26, Io 6.0-9.0, Tp 380-500, Tps 270-340, Tmin < -13, m < -18. [Teco-Uote-Lhu].

Table 43 shows seven relevés sampled in high altitude mountain areas in Alberta Canadian Rockies (Canadian Rockies Subsector). Abies bifolia (Rocky Mountain subalpine fir) and Picea engelmannii var. engelmannii (Engelmann spruce) are only the trees growing in the forest community, and both species tends to form closed clumps of trees at the timberline. In the understory a high number of arctic-boreo-alpine species characterize geographically this association: Empetrum nigrum subsp. hermaphroditum, Phyllodoce glanduliflora, Arctostaphylos rubra, Salix glauca var. villosa, Salix reticulata subsp. nivalis, Cassiope tetragona s. l., Betula glandulosa, Dryas hookeriana, Kobresia myosuroides, etc.

Table 43
9d. Empetro hermaphroditi-Abietetum bifoliae

(Piceo-Abietion bifoliae, Pseudotsugo-Abietetalia bifoliae)

Altitude (1=10m) 198 202 185 204 182 175 203 193
Number of species 16 16 17 17 17 18 22 17
Ordinal number 1 2 3 4 5 6* 7 8
Trees:
Abies bifolia 4 3 3 4 3 3 3 V
Picea engelmannii 3 3 2 2 4 3 3 V
Characteristic species:
Empetrum hermaphroditum 3 2 2 2 3 4 2 V
Vaccinium scoparium 3 1 2 3 2 2 1 V
Phyllodoce glanduliflora 2 3 3 2 . 1 2 V
Arctostaphylos rubra + 2 . 2 3 + 2 V
Salix villosa . 1 + + 1 2 2 V
Pentaphylloides floribunda 1 1 . + + . 1 IV
Cassiope tetragona . + 3 1 . + 3 IV
Juniperus depressa . 1 . 1 2 + 1 IV
Ledum groenlandicum 2 . + . 2 2 . III
Salix nivalis 2 . + . 1 . 2 III
Pyrola chlorantha 1 1 . + . . . III
Vaccinium minus + . 1 . . 2 . III
Linnaea americana 1 . . . 1 + . III
Arctostaphylos adenotricha . 2 . 1 2 . . III
Pulsatilla multifida . + . 2 . . 1 III
Gymnocarpium dryopteris . . 2 + . 1 . III
Cornus canadensis . . 1 . . 1 . II
Luzula fastigiata . . 1 . . 1 . II
Leptarrhena pyrolifolia . . + . . . + II
Senecio triangularis . . . 1 . . + II
Shepherdia canadensis . . . . 2 1 . II
Betula glandulosa . . . . . 1 2 II
Companion species:
Epilobium angustifolium 2 + + 1 + + 1 V
Kobresia myosuroides . + . + . . 1 III

Other species. Trees: Pinus latifolia + in 5. Characteristic species: Aster conspicuus 1, Poa stenantha 1, Salix prolixa 1 in 1. Moneses uniflora 1, Zigadenus elegans 1 in 5. Pyrola asarifolia 2, Equisetum scirpoides 1, Phyllodoce empetriformis 1, Phyllodoce xintermedia + in 7. Companion species: Dryas hookeriana 1 in 2 and 7. Epilobium latifolium 2, Oxyria digyna 1 in 3.

Localities: 1. Alberta: Banff National Park, between Bow Lake and Bow Summit. 51º48'N-116º28'W. SW, 10%, 20 m, 80 cm, 400 m2 (reg. 1992e: 44). 2. Alberta: Banff National Park, Sunwapta Pass. 52º15'N-117º09'W. SE, 15%, 10 m, 60 cm, 100 m2 (reg. 1995d: 144). 3. Alberta: Jasper National Park, Mount Edith Cavell (Lake and Glacier). 52º43'N-118º02'W. N, 5%, 5 m, 30 cm, 50 m2 (reg. 1992e: 59). 4. Alberta: Sunwapta Pass, Banff National Park. 52º15'N-117º10'W. E, 10%, 15 m, 50 cm, 100 m2 (reg. 1995d: 143). 5. Alberta: Banff National Park, Bow Pass to Peyto Lake. 51º50'N-116º31'W. SW, 15%, 18 m, 90 cm, 400 m2 (reg. 1992e: 45). 6. Alberta: Jasper National Park, Mount Edith Cavell. 52º44'N-118º02'W. NW, 20%, 15 m, 70 cm, 400 m2, holotypus ass. (reg. 1992e: 57). 7. Alberta: Jasper National Park, Columbia Icefield, Athabasca Glacier. 52º13'N-117º21'W. N, 20%, 10 m, 60 cm, 100 m2 (reg. 1992e: 54). 8. Synthesized table.

Type relevé (holotypus): Table 43, relevé n. 6. Rivas-Martínez reg. 1992e: 57. 19.08.92. Site: Alberta: Jasper National Park, Mount Edith Cavell. 52º44'N-118º02'W. 1750 m, NW, 20%, 15 m, 70 cm, 400 m2. Physiognomy and habitat: Rocky Mountain Subalpine fir (Abies bifolia) and Engelmann spruce (Picea engelmannii var. engelmannii) mesoforest. Estimated bioclimatic factors: Continental Temperate, subcontinental (Ic ~ 24), upper orotemperate (Tp ~ 420), lower humid (Io ~ 7), Positive Summer Temperature Tps ~ 320. Biogeographic location: Rocky Mountain Regio, Rocky Mountain Subregion, Northern Rocky Mountain Province, Canadian Rockies Sector. Floristic combination: Linnaeo-Piceetea characteristic species, trees: 3 Abies bifolia, 3 Picea engelmannii. Others: + Arctostaphylos rubra, 1 Betula glandulosa, + Cassiope tetragona var. tetragona, 1 Cornuscanadensis, 4 Empetrum nigrum subsp. hermaphroditum, 1 Gymnocarpium dryopteris, + Juniperus communis var. depressa, 2 Ledum groenlandicum, + Linnaea americana, 1 Luzula parviflora subsp. fastigiata, 1 Phyllodoce glanduliflora, 2 Salix glauca var. villosa, 1 Shepherdia canadensis, 2 Vaccinium vitis-idaea subsp. minus, 2 Vaccinium scoparium. Companion species: + Epilobium angustifolium.

Remarks: The type relevé of the association Abieti bifoliae-Piceetum engelmannii Peinado, Aguirre & Cruz 1998 in Plant Ecology 137: 193, tb. 19, no. 480 (Alberta: Sunwapta Pass, 2000 m, S) shows in 200 square meters eighteen species sampled. Some of the recognized species as "Betula nana" or "Picea engelmannii x glauca" never can be found in Canadian Rocky Mountains inside the Engelmann spruce-subalpine fir upper subalpine micro-mesoforests with Arctostaphylos rubra, Cassiope tetragona s. l., Empetrum nigrum subsp. hermaphroditum, Phyllodoce glanduliflora, Salix reticulata subsp. nivalis, etc. Consistently we considere that the name should be rejected as "nomen dubium" because it is so complex that its assignment to any association distinguished today does not seem possible (art. 37).

Addendum: To compare easily we transcribe the type relevé (holotypus) of Abieti bifoliae-Piceetum engelmannii Peinado, Aguirre & Cruz in Plant Ecology 137: 193, tb. 19, relevé 480. 1998 (nom. dub., art. 37). Alberta: Sunwapta Pass, altitude 2000 m, area 200 m2, exposure SW: 2 Abies bifolia, 2 Arctostaphylos uva-ursi, 1 Betula "nana" [B. glandulosa], 1 Cassiope tetragona, + Epilobium angustifolium, 1 Fragaria virginiana, 3 Juniperus communis var. depressa, 2 Leymus innovatus, 1 Pentaphylloides floribunda, 2 Phyllodoce glanduliflora, 2 Picea engelmannii, 2 Picea "glauca x engelmannii" [P. engelmannii var. engelmannii], + Pinus contorta var. latifolia, 1 Pyrola chloranta, 1 Salix "glauca" [S. glauca var. villosa], 1 Shepherdia canadensis, 1 Solidago multiradiata, 2 Vaccinium scoparium.

9e. Piceetum engelmannio-albertianae associatio nova hoc loco

Continental Temperate (subcontinental and barely eucontinental); orotemperate and hemiboreal; upper dry and subhumid; climactical meso- and macroforests with Alberta spruce (Picea glauca var. albertiana), Engelmann spruce (Picea engelmannii var. engelmannii), white spruce (Picea glauca var. glauca) and Rocky Mountain subalpine fir (Abies bifolia) as main trees; at lower altitudes and less continental territories, Rocky Mountain Douglas fir (Pseudotsuga menziesii var. glauca) becomes frequent. These coniferous forests spreading into Canadian Rockies and Fraser Interior Plateau territories and grow on dystric, haplic, ferric and gleyic podzols, podzo-luvisols, and dystric cambisols. The dynamic pattern of this forest association shows a replacement by the micro- and mesoforests of Empetro hermaphroditi-Abietetum bifoliae association at the high altitude mountain areas in Canadian Rockies, with absence of Picea glauca var. glauca and Picea glauca var. albertiana. The fire disturbance force the replacement of Piceetum engelmannio-albertianae climactical forests by the seral lodgepole pine forests belonging to Vaccinio scoparii-Pinetum latifoliae association on dry soils, and on mesic soils by the seral balsam poplar-quacking aspen deciduous forests belonging to Spiraeo lucidae-Populetum balsamiferae association.

Bioclimatic diagnosis: Ic 25-30, Io 3.2-6.0, Tp 500-800, Tps 390-440, Tmin < -10, m < -15. [Teco, Texe-Ote, Hbo-Udry, Shu-Stp].

Table 44 shows 11 relevés from Alberta and British Columbia, in the Canadian Rockies and Fraser Interior Plateau Sectors (Northern Rocky Mountain Province). Picea glauca var. glauca, Picea glauca var. albertiana, Picea engelmannii var. engelmannii, and Abies bifolia are the main trees, and in warmer summer habitats in British Columbia Pseudotsuga menziesii var. glauca becomes frequent. Pinus contorta var. latifolia, Betula papyrifera, Populus balsamifera subsp. balsamifera and Populus tremuloides are the commonest trees in ancient disturbed forests. In the understory are common some shrubs such as Vaccinium membranaceum, Ribes lacustre, Rosa acicularis subsp. sayi, Shepherdia canadensis, Cornus sericea subsp. sericea and Spiraea betulifolia var. lucida; between the herbs it could be mentioned: Linnaea americana, Cornus canadensis, Pyrola asarifolia, Clintonia uniflora and Aralia nudicaulis.

 Table 44
9e. Piceetum engelmannio-albertianae

(Piceo-Abietion bifoliae, Pseudotsugo-Abietetalia bifoliae)

Altitude (1=10m) 148 158 124 105 120 70 65 82 63 86 64 99
Number of species 22 23 24 25 26 29 32 32 33 33 35 28
Ordinal number 1 2 3 4 5 6 7* 8 9 10 11 12
Trees:
Picea albertiana 3 3 2 3 3 2 2 2 2 3 3 V
Picea engelmannii 2 2 3 1 2 3 3 3 + 1 1 V
Abies bifolia 2 2 1 1 . 3 3 3 . 1 . IV
Picea glauca 1 . 1 2 2 . . 1 . . 1 III
Pinus latifolia + . 1 . . . + . 1   1 III
Betula papyrifera . . . . . + + . 1 1 + III
Pseudotsuga glauca . . . . . . . . 3 2 2 II
Characteristic species:
Linnaea americana 3 4 2 4 3 1 2 2 1 2 2 V
Cornus canadensis 1 1 2 4 2 2 3 3 2 3 3 V
Pyrola asarifolia + 1 + 2 2 2 1 1 2 + . V
Vaccinium membranaceum 2 1 3 1 2 2 2 3 1 . 2 V
Ribes lacustre 1 1 1 2 1 1 . 2 . 1 + IV
Rosa sayi + + 2 2 1 . 1 . 1 + 3 IV
Shepherdia canadensis 2 2 3 + 2 . . + . . + IV
Viburnum edule . . . 1 . 2 1 2 + 1 2 IV
Clintonia uniflora . . . . . 3 3 2 2 3 2 IV
Amelanchier alnifolia . + . 1 1 . . . 2 1 3 IV
Salix prolixa + 1 2 + 1 . . . . . . III
Osmorhiza depauperata 1 . . 1 . 1   1 1 . . III
Viola glabella . + . . . + + . + + . III
Cornus sericea . 1 . . . 2 . . 1 1 3 III
Spiraea lucida . . . 1 . . 2 2 2 . 2 III
Aralia nudicaulis . . . . . . 2 1 1 3 1 III
Rubus parviflorus . . . . . . 1 2 1 1 1 III
Ledum groenlandicum 1 3 2 . 2 . . . . . . II
Juniperus depressa 1 1 2 . 2 . . . . . . II
Orthilia secunda . 2 . . . 2 . 2 2 . . II
Chimaphila occidentalis . . . . . . . + 3 + 3 II
Companion species:
Epilobium angustifolium 1 + 2 1 1 1 1 1 1 + 1 V
Ptilium crista-castrensis . 2 2 2 3 2 3 3 1 1 2 V
Hylocomium splendens 3 5 3 4 3 . . 3 . 2 2 IV

Other species. Trees: Populus tremuloides + in 3, 5 and 11. Populus balsamifera 1 in 5. Acer glabrum 2 in 6. Populus trichocarpa + in 10. Characteristic species: Delphinium glaucum + in 2, 1 in 6, 7 and 9. Galium boreale 1 in 4, 6 and 10, 2 in 11. Lonicera involucrata 1 in 4 and 11, 2 in 7 and 10. Tiarella unifoliata 2 in 6 and 8, + in 7, 1 in 10. Gymnocarpium dryopteris + in 6, 3 in 7 and 8, 2 in 10. Actaea rubra 2 in 4, 1 in 8 and 10. Rubus pedatus 3 in 6, 2 in 7 and 8. Lycopodium annotinum 1 in 6 and 11, 3 in 7. Disporum smithii 1 in 7, 2 in 9 and 11. Maianthemum amplexicaule 2 in 8, 9 and 10. Pyrola minor 2 in 1, + in 4. Juniperus horizontalis + in 1, 1 in 5. Zigadenus elegans + in 3, 1 in 5. Hedysarum americanum + in 3 and 5. Aster conspicuus 1 in 4, 2 in 5. Rubus strigosus + in 3 and 10. Dryopteris expansa 2 in 6, 1 in 7. Rubus pubescens 1 in 6 and 7. Veratrum viride 1 in 6 and 11. Vaccinium caespitosum 2 in 7, 3 in 9. Goodyera repens 1 in 7 and 9. Coelocaulon lividum 1 in 7 and 11. Alnus sinuata 1 in 8, + in 9. Sorbus scopulina 1 in 9 and 11. Thalictrum occidentale 1 in 9, + in 11. Pentaphylloides floribunda 1 in 1. Arctostaphylos uva-ursi 1, Calamagrostis rubescens 1 in 2. Vaccinium minus 3, Melampyrum lineare 1 in 3. Mertensia paniculata 1 in 4. Solidago missouriensis 1, Betula xdutillyi + in 5. Vaccinium ovalifolium 3, Oplopanax horridus 2 in 6. Gaultheria hispidula 1 in 7. Goodyera oblongifolia 2, Elymus glaucus 1, Diphasiastrum complanatum 1, Thalictrum venulosum 1, Aquilegia formosa + in 8. Mitella nuda 2, Paxistima myrsinites 2, Mahonia repens +, Disporum hookeri + in 10. Aster ciliolatus + in 11. Companion species: Pleurozium schreberi 2 in 7, 9 and 11. Rhytidiadelphus triquetrus 2 in 9 and 11. Dryas drummondii 1 in 1. Oxytropis spicata + in 5.

Localities: 1. Alberta: Jasper National Park, Sunwapta River close to Jonas Creek. 52º25'N-117º24'W. SW, 10%, 25 m, 50 cm, 400 m2 (reg. 1992e: 46). 2. Alberta: Jasper National Park, Sunwapta River close to Stanley Falls. 52º21'N-117º20'W. S, 20%, 20 m, 50 cm, 200 m2 (reg. 1995d: 139). 3. Alberta: Jasper National Park, Athabasca Falls. 52º39'N-117º52'W. N, 5%, 18 m, 40 cm, 400 m2 (reg. 1992e: 56). 4. Alberta: Jasper National Park-Jasper, Whistlers Campground. 52º52'N-118º06'W. N, 15%, 35 m, 70 cm, 1000 m2 (reg. 1992e: 70). 5. Alberta: Jasper National Park-Jasper, Maligne Canyon close to Maligne River. 52º55'N-117º55'W. NW, 10%, 25 m, 50 cm, 400 m2 (reg. 1992e: 69). 6. British Columbia: Hart Ranges, between Pine Pass and Chetwynd close to Pine River. 55º30'N-122º31'W. N, 25%, 30 m, 80 cm, 500 m2 (reg. 1995d: 151). 7. British Columbia: McKenzie close to Williston Lake. 55º19'N-123º02'W. W, 15%, 35 m, 60 cm, 400 m2, holotypus ass. (reg. 1995d: 150). 8. British Columbia: Hart Ranges, Pine Pass to Chetwynd. 55º25'N-122º38'W. SW, 30%, 30 m, 60 cm, 400 m2 (reg. 1992e: 84). 9. British Columbia: Bear Lake, Crooked River Provincial Park. Crooked River. 54º28'N-122º36'W. SW, 25%, 30 m, 40 cm, 400 m2 (reg. 1995d: 149). 10. British Columbia: Between Quesnel and Kersley. 52º55'N-122º26'W. N, 30 m, 60 cm, 2000 m2 (reg. 1997: 40). 11. British Columbia: Between Prince George and Summit Lake, Salmon Valley close to Salmon River. 54º06'N-122º38'W. S, 20%, 35 m, 60 cm, 400 m2 (reg. 1995d: 148). 12. Synthesized table.

Type relevé (holotypus): Table 44, relevé n. 7. Rivas-Martínez reg. 1995d: 150. 06.09.95, made with Dr. Costa. Site: British Columbia: McKenzie close to Williston Lake. 55º19'N-123º02'W. 650 m, W, 15%, 35 m, 60 cm, 400 m2. Physiognomy and habitat: Engelmann spruce (Picea engelmannii var. engelmannii) and western white spruce (Picea glauca var. albertiana) macroforest with Rocky Mountain subalpine fir (Abies bifolia) and lodgepole pine (Pinus contorta var. latifolia). Estimated bioclimatic factors: Continental Temperate, subcontinental (Ic ~ 26), lower orotemperate (Tp ~ 620), upper subhumid (Io ~ 5.5), Positive Summer Temperature (Ts ~ 420). Biogeographic location: Rocky Mountain Region, Rocky Mountain Subregion, Northern Rocky Mountain Province, Canadian Rockies Sector. Floristic combination: Linnaeo-Piceetea characteristic species, trees: 3 Abies bifolia, + Betula papyrifera var. papyrifera, 3 Picea engelmannii var. engelmannii, 2 Picea glauca var. albertiana, + Pinus contorta var. latifolia. Others: 2 Aralia nudicaulis, 3 Clintonia uniflora, 1 Coelocaulon lividum, Cornus canadensis, 1 Delphinium glaucum, 1 Disporum smithii, 1 Dryopteris expansa, 1 Gaultheria hispidula, 1 Goodyera repens, 3 Gymnocarpium dryopteris, 2 Linnaea americana, 2 Lonicera involucrata, 3 Lycopodium annotinum, 1 Pyrola asarifolia, 1 Rosa acicularis subsp. sayi, 1 Rubus parviflorus, 2 Rubus pedatus, 1 Rubus pubescens, 2 Spiraea betulifolia var. lucida, + Tiarella trifoliata var. unifoliata, 2 Vaccinium caespitosum, 2 Vaccinium membranaceum, 1 Viburnum edule, + Viola glabella. Companion species: 1 Epilobium angustifolium, 2 Pleurozium schreberi, 3 Ptilium crista-castrensis.

9f. Piceetum pungentis associatio nova hoc loco

Climactical and permanent edapho-hygrophilous meso- and macroforests spreading into Continental Temperate (subcontinental) territories; lower orotemperate; dry, subhumid and lower humid, often submediterranean. The main trees in these forests are Picea pungens (blue spruce), Abies bifolia (Rocky Mountain subalpine fir), Pseudotsuga menziesii var. glauca (Rocky Mountain Douglas fir), Picea pungens x engelmannii (hybrid between blue and Engelmann spruce), and in disturbed forest Pinus contorta var. latifolia (lodgepole pine) and Populus tremuloides (quacking aspen). Piceetum pungentis forest association spreading into Utah Rockies and Colorado Rockies territories and grow on haplic, cambic and ferric podzols, podzo-luvisols and dystric cambisols. The blue spruce forest association is replaced at higher altitude areas by the Engelmann spruce and subalpine fir forest association Vaccinio scoparii-Abietetum bifoliae. The Piceetum pungentis dynamic pattern shows a replacement by the ubiquitous seral lodgepole pine forest association Vaccinio scoparii-Pinetum latifoliae by fire disturbances on dry soils, and on mesic or wet soils by the seral clonal quacking-aspen deciduous forest association Symphoricarpo utahensis-Populetum tremuloidis.

Bioclimatic diagnosis: Ic 23-28, Io 3.6-7.0, Tp 600-800, Tps 380-450, Tmin < -7, m < -13. [Teco-Ote-Shu, Lhu-Stp, Sbm].

Table 45 gives eleven relevés from Utah, Wyoming and Colorado, in the Utah and Colorado Rockies Sectors (Central-Eastern Rocky Mountain Province). Picea pungens (blue spruce) is the main tree in the canopy, often with Abies bifolia, Pseudotsuga menziesii var. glauca and hybrids between Picea pungens and P. engelmannii var. engelmannii. Lodgepole pine (Pinus contorta var. latifolia) is usual due to ancient disturbances (usually by fires) and the transitions between the seral lodgepole pine forests (Vaccinio-Pinetum latifoliae) and the climactical blue spruce forests (Piceetum pungentis) are common all over theUtah and Colorado Rockies. Populus tremuloides grows on mesic disturbed habitats, and his usual growth by clumps of clones gives easily great quacking aspen groves. In the understory are usually abundant shrubs such as Paxistima myrsinites, Rosa woodsii var. ultramontana, Symphoricarpos oreophilus var. utahensis, Juniperus communis var. depressa, Ribes montigenum and Amelanchier alnifolia s. l.; between the herbaceous layer we could remark some mycorrhizal herbs such as Pyrola chlorantha, Pyrola asarifolia, Orhilia secunda and Goodyera oblongifolia.

Table 45
9f. Piceetum pungentis

(Piceo-Abietion bifoliae, Pseudotsugo-Abietetalia bifoliae)

Altitude (1=10m) 242 270 273 250 246 260 270 264 175 255 256 251
Number of species 18 18 19 19 20 20 20 21 21 22 23 20
Ordinal number 1 2 3 4 5 6 7* 8 9 10 11 12
Trees:
Picea pungens 5 3 4 4 4 4 4 4 5 3 4 V
Abies bifolia 1 3 1 3 . . 3 2 1 2 . IV
Pseudotsuga glauca 1 1 . . . 1 . + 1 3 1 IV
Pinus latifolia + . 2 . 2 2 . + 1 . 1 IV
Picea engelmannii x pungens . 1 . . + 1 1 . + 1 1 IV
Populus tremuloides + . + . 1 1 . . 1 + . III
Characteristic species:
Rosa ultramontana 1 + + 1 2 + 1 + 2 . 1 V
Paxistima myrsinites 2 2 . 1 . + 1 2 2 2 . IV
Pyrola chlorantha + + . 1 . 2 . 2 1 1 1 IV
Symphoricarpos utahensis 2 3 . 2 . . 1 + 3 2 . IV
Galium boreale + 1 + + 2 . . . . 1 . III
Pyrola asarifolia . + . + . 2 1 . . 1 1 III
Juniperus depressa 3 . 2 . 3 3 . . . . 2 III
Ribes montigenum 2 . 1 . . . 3 2 . + . III
Thalictrum sparsiflorum 1 . . 2 . . . 1 2 2 . III
Orthilia secunda . 3 1 + . . . . . 1 . II
Goodyera oblongifolia . 1 . 1 . . . 2 . 1 . II
Amelanchier alnifolia . + . 2 . . . . 3 1 . II
Solidago scopulorum . 2 . . 1 1 . . . . + II
Osmorhiza berteroi . + . . . . 1 2 . 1 . II
Aster engelmannii . . + . 1 3 + . . . . II
Antennaria rosea + . . . . . + . . . 1 II
Arnica rydbergii . 3 2 . . . . . . . 2 II
Lonicera utahensis . 1 . . . . 1 . 1 . . II
Calamagrostis rubescens . . 1 . . 2 . . . . 1 II
Lonicera involucrata . . . 2 1 . . 1 . . . II
Companion species:
Epilobium angustifolium . . 2 1 . + . + 1 . 2 III
Fragaria bracteata . . . . 1 2 + . . 1 2 III
Pseudostellaria jamesiana . . . . . . 3 . 2 1 . II

Other species. Trees: Picea engelmannii 2 in 2, 1 in 10. Pinus scopulorum + in 5 and 6. Acer glabrum 2 in 9. Characteristic species: Physocarpus malvacens 1 in 1, 2 in 10. Vaccinium oreophilum 3 in 3 and 11. Linnaea americana 2 in 3, 3 in 11. Maianthemum amplexicaule 1 in 3 and 9. Geranium viscosissimum 1 in 4, 2 in 9. Ribes cereum 2 in 5, + in 6. Shepherdia canadensis 3 in 6, 2 in 11. Actaea arguta + in 7 and 8. Mitella pentandra 2 in 7 and 10. Sorbus scopulina 1 in 8 and 10. Elymus glaucus 1 in 9 and 11. Mahonia repens 1 in 1. Sambucus pubens 2, Thermopsis divaricarpa 1 in 3. Veratrum viride 2, Streptopus chalazatus 2, Thalictrum fendleri 1, Valeriana acutiloba 1 in 4. Arctostaphylos uva-ursi 2, Pentaphylloides floribunda 2, Delphinium barbeyi + in 5. Moneses uniflora 1 in 6. Aquilegia ochroleuca 2, Rudbeckia montana + in 7. Erythronium grandiflorum 2, Viola renifolia 1, Chimaphila occidentalis +, Corallorhiza trifida + in 8. Spiraea lucida 1 in 9. Polemonium delicatum 2, Vaccinium cespitosum 1, Vaccinium scoparium 1 in 11. Companion species: Poa fendleriana 2 in 1 and 7, + in 11. Campanula rotundifolia 1 in 3 and 5. Achillea occidentalis 1 in 5 and 11. Gentianella acuta 1 in 1. Cirsium oregonense 1, Ribes inerme 1 in 5. Jamesia americana 2 in 6. Potentilla pensylvanica 1 in 7. Linanthus nuttallii 1 in 8. Sambucus cerulea 2 in 9.

Localities: 1. Utah: Daggett Co., Ashley National Forest, between Greendale Junction and Vernal, Red Springs. 40º48'N-109º28'W. NW, 10%, 400 m2 (reg. 1995d: 47). 2. Utah: Wasatch Co., Midway, Wasatch Mountain State Park. Guardsman Pass Road. 40º36'N-111º26'W. NW, 20%, 25 m, 35 cm, 400 m2 (reg. 1996b: 38). 3. Colorado: Boulder Co., Roosevelt National Forest, between Ward and Nederland Peak to Peak Hwy. 40º04'N-105º32'N. N, 25%, 25 m, 35 cm, 200 m2 (reg. 1995d: 10). 4. Utah: Wasatch Co. Midway, Wasatch Mountain State Park, Guardsman Pass Road. 40º42'N-111º29'W. S, 10%, 400 m2 (reg. 1996b: 36). 5. Colorado: Boulder Co. Roosevelt National Forest, between Cardinal and Caribou. 39º59'N-105º35'W. S, 10%, 25 m, 35 cm, 400 m2 (reg. 1995d: 8). 6. Colorado: Clear Creek Co. Arapaho National Forest, between Idaho Springs and Mt. Evans, Mt. Evans Hwy. Echo Lake Park. 39º41'N-105º37'W. N, 30%, 25 m, 35 cm, 400 m2 (reg. 1995d: 15). 7. Utah: Rich Co. Wasatch-Cache National Forest, Monte Cristo Range, between Willows and Monte Cristo Pass. 41º33'N-111º29'W. NW, 20%, 25 m, 100 cm, 400 m2, holotypus ass. (reg. 1996b: 41). 8. Colorado: Grand Co. Routt National Forest Muddy Pass. 40º23'N-106º35'W. N, 10%, 25 m, 35 cm, 400 m2 (reg. 1995d: 44). 9. Wyoming: Lincoln Co. Targhee National Forest, Alpine Junction. Grand Canyon of Snake River. 43º13'N-110º55'W. E, 20%, 30 m, 60 cm, 400 m2 (reg. 1996b: 45). 10. Utah: Wasatch Co. Midway. Wasatch Mountain State Park. Guardsman Pass Road. 40º38'N-111º26'W. N, 20%, 25 m, 60 cm, 400 m2 (reg. 1996b: 37). 11. Colorado: Grand Co. Arapaho National Forest. Rocky Mountain National Park, between Timber Lake Trail and Grand Lake. Onahn Creek. 40º19'N-105º51'W. W, 10%, 25 m, 35 cm, 400 m2 (reg. 1995d: 30). 12. Synthesized table.

Type relevé (holotypus): Table 45, relevé n. 7. Rivas-Martínez reg. 1996b: 41. 28.08.96, made with Drs. Llorens and Sánchez-Mata. Site: Utah: Rich Co. Wasatch-Cache National Forest. Monte Cristo Range. Between Willows and Monte Cristo Pass. 41º33'N-111º29'W. 2700 m, NW, 20%, 25 m, 100 cm, 400 m2. Physiognomy and habitat: Mature Colorado blue spruce (Picea pungens) and Rocky Mountain fir (Abies bifolia) mesoforest. Estimated bioclimatic factors: Continental Temperate, subcontinental (Ic ~ 25), lower orotemperate (Tp ~ 650), upper subhumid (Io ~ 5.5), Positive Summer Temperature Tps ~ 400. Biogeographic location: Rocky Mountain Region, Rocky Mountain Subregion, Central-Eastern Rocky Mountain Province, Utah Rockies Sector. Floristic combination: Linnaeo-Piceetea characteristic species, trees: 3 Abies bifolia, 4 Picea pungens, 1 Picea pungens x engelmannii. Others: + Actaea rubra subsp. arguta, + Antennaria rosea, + Aster engelmannii, 1 Lonicera utahensis, 2 Mitella pentandra, 2 Aquilegia coerulea var. ochroleuca, 1 Osmorhiza berteroi, 1 Paxistima myrsinites, 3 Pseudostellaria jamesiana, 3 Ribes montigenum, 1 Rosa woodsii var. ultramontana, + Rudbeckia occidentalis var. montana, 1 Symphoricarpos oreophilus var. utahensis. Companion species:1 Fragaria vesca subsp. bracteata, 2 Poa fendleriana, 1 Potentilla pensylvanica.