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Group 1 -- Ferns and Horsetails

Group 2 -- Grasses

Group 3 -- Sedges

Group 4 -- Other Monocots

Group 5 -- Trees or Shrubs, including Woody Vines

Group 6 -- Dicot Herbs with Some Leaves Compound

Group 7 -- Dicot Herbs with Most or All of the Leaves Simple and Opposite or Whorled

Group 8 -- Dicot Herbs with All the Leaves Simple and Basal and/or Alternate

Identification Key

Southern Maiden-hair Fern (Adiantum capillus-veneris L.)

Northern Maiden-hair Fern (Adiantum pedatum L.)

Subarctic Lady Fern (Athyrium filix-femina (L.) Roth)

Triangle Moonwort (Botrychium lanceolatum (S.G. Gmel.) Rupr.)

Moonwort (Botrychium lunaria (L.) Swartz)

Spiny-spore Quillwort (Isoetes echinospora Durieu)

Western Quillwort (Isoetes lacustris L.)

Hairy Water Fern (Marsilea uestita Hook. & Grev.)

Giant Chain fern (Woodwardia fimbriata J.E. Smith)

Spike Bentgrass (Agrostis exarata Trin.)

Idaho Bentgrass (Agrostis idahoensis Nash)

Slender Wheatgrass (Agropyron trachycaulum (Link) Malte ex H F. Lewis)

Short-awn Foxtail (Alopecurus acqualis Sobol.)

Mountain Foxtail (Alopecurus alpinus J.E. Smith)

Giant Reed (Arundo donox L.)

American Sloughgrass (Beckmannia syzigachne (Steud.) Fernald)

Narrow-spike Small-reedgrass (Calamagrostis inexpansa Gray)

Slimstem Reedgrass (Calamagrostis neglecta (Ehrh.) P. Gaertn., B. Meyer & Scherb.)

Brookgrass (Catabrosa aquatica (L.) Beauv.)

Slender Wood-reedgrass (Cinna latifolia (Trevir.) Griseb.)

California Oatgrass (Danthonia californica Boland.)

Tufted Hairgrass (Deschampsia cespitosa (L.) Beauv.)

Annual Hairgrass (Deschampsia danthonioides (Trin.) Munro)

Slender Hairgrass (Deschampsia elongata (Hook.) Munro)

Inland Saltgrass (Distichlis stricta (Torr.) Scribn.)

Basin Wild-rye (Elymus cinereus Scribn. & Merrill)

Creeping Wild-rye (Elymus triticoides Buckley)

Small Floating Manna Grass (Glyceria borealis (Nash) Batch.)

Tall Manna Grass (Glyceria elata (Nash ex Rydb.) M.E. Jones)

Holy Grass (Hierochloe odorata (L.) Beauv.)

Common Velvet Grass (Holcus lanatus L.)

Meadow Barley (Hordeum brachyantherum Nevskii)

Bearded Sprangle-top (Leptochloa fascicularis (Lam.) Gray)

Alkali Muhly (Muhlenbergia asperifolia (Nees & Meyer ex Trin.) Parodi)

Fall Panic Grass (Panicum dichotomiflorum Michx.)

Timothy (Phleum pretense L.)

Alkali Bluegrass (Poa juncifolia Scribn.)

Bog Bluegrass (Poa leptocoma Trin.)

Nevada Bluegrass (Poa nevadensis Vasey ex Scribn.)

Fowl Bluegrass (Poa palustris L.)

Annual Rabbit-foot Grass (Polypogon monspeliensis (L.) Desf.)

Nuttall Alkali Grass (Puccinellia airoides (Nutt.) S. Wats. & Coult.)

Weeping Alkali Grass (Puccinellia distans (L.) Parlat.)

Weak Manna Grass (Puccinellia pauciflora (J. Presl) Munz)

Alkali Cordgrass (Spartina gracilis Trin.)

Alkali Sacaton (Sporobolus airoides (Torr.) Torr.)

Spiked False-oats (Trisetum spicatum (L.) Richter)

Slender-beak Sedge (Carex athrostachya Olney)

Golden-fruit Sedge (Carex aurea Nutt.)

Showy Sedge (Carex bella L.H. Bailey)

Brown Bog Sedge (Carex buxbaumii Wahlenb.)

Hoary Sedge (Carex canescens L.)

Lesser Panicled Sedge (Carex diandra Schrank)

Douglas' Sedge (Carex douglasii Boott)

Kellogg's Sedge (Carex kelloggii W. Boott)

Shore Sedge (Carex lenticularis Michx.)

Bristly-stalk Sedge (Carex leptalea Wahlenb.)

Mud Sedge (Carex limosa L.)

Wood-rush Sedge (Carex lazulina Olney)

Small-wing Sedge (Carex microptera Mackenz.)

Nebraska Sedge (Carex nebrascensis Dewey)

Clustered Field Sedge (Carex praegracilis W. Boott)

Raynolds' Sedge (Carex raynoldsii Dewey)

Beaked Sedge (Carex rostrata J. Stokes)

Russet Sedge (Carex saxatilis L.)

Holm's Rocky Mountain Sedge (Carex scopulorum Th. Holm)

Short-beak Sedge (Carex simulata Mackenz.)

Inflated Sedge (Carex vesicaria L.)

Little Green Sedge (Carex viridula Michx.)

Awned Flatsedge (Cyperus aristatus Rottb.)

Creeping Spikerush (Eleocharis macrostachya Britton)

Few-flower Spikerush (Eleocharis pauciflora (Lightf.) Link)

Beaked Spikerush (Eleocharis rostellata (Torr.) Torr.)

Slender Cotton-grass (Eriophorum gracile W. Koch)

Scheuchzer's Cotton-grass (Eriophorum scheuchzeri Hoppe)

Tufted Bulrush (Scirpus cespitosus L.)

Saltmarsh Bulrush (Scirpus maritimus L.)

Small-fruit Bulrush (Scirpus microcarpus J. & K. Presl)

Cloaked Bulrush (Scirpus pallidus (Britton) Fernald)

Three-square Bulrush (Scirpus pungens Vahl)

Narrow-leaf Water-plantain (Alisma gramineum Lej.)

Tall Swamp Onion (Allium validum S. Wats.)

Garden Asparagus-fern (Asparagus officinalis L.)

Common Camassia (Camassia quamash (Pursh) Greene)

Small Yellow Lady's-slipper (Cypripedium calceolus L.)

Jointed Rush (Juncus articulates L.)

Two-flower Rush (Juncus biglumis L.)

Chestnut Rush (Juncus castaneus J. E. Smith)

Colorado Rush (Juncus confuses Coville)

Drummond's Rush (Juncus drummondii E. Meyer)

Three-stamen Rush (Juncus ensifolius Wikst.)

Long-style Rush (Juncus longistylis Torr.)

Merten's Rush (Juncus mertensianus Bong.)

Mexican Rush (Juncus mexicanus Willd. ex J.A. & J.H. Schultes)

Sierra Rush (Juncus nevadensis S. Wats.)

Three-flower Rush (Juncus triglumis L.)

Star Duckweed (Lemna trisulca L.)

Pale Duckweed (Lemna valdiviana Philippi)

Flowering Quillwort (Lilaea scilloides (Poir.) Haum.)

Broad-leaf Twayblade (Listera convallarioides (Swartz) Nutt. ex Elliott)

Small-flower Woodrush (Luzala parviflora (Ehrh.) Desv.)

Spiked Woodrush (Luzula spicata (L.) DC.)

Fringed Water-plantain (Machaerocarpus californicus (Torn ex Benth.) Small)

Southern Naiad (Najas guadalupensis (Spreng.) Morong)

Leafy White Orchid (Platanthera dilatata (Pursh) Lindl. ex Beck)

Fine-leaf Pondweed (Potamogeton filiformis Pers.)

Floating-leaf Pondweed (Potamogeton natans L.)

Long-leaf Pondweed (Potamogeton nodosus Pair.)

Sago Pondweed (Potamogeton pectinatus L.)

White-stem Pondweed (Potamogeton praelongus Wulfen)

Small Pondweed (Potamogeton pusillus L.)

Richardson Pondweed (Potamogeton richardsonii (Ar. Benn.) Rydb.)

Robbin's Pondweed (Potamogeton robbinsii Oakes)

Flat-stem Pondweed (Potamogeton zosteriformis Fernald)

Widgeon-grass (Ruppia maritima L.)

Northern Arrow-head (Sagittaria cuneata Sheldon)

Broad-leaf Arrow-head (Sagittaria latifolia Willd.)

Idaho Blue-eye-grass (Sisyrinchium idahoense Bickn.)

Starry False-Solomon's-seal (Smilacina stellata (L.) Desf.)

Small Burreed (Sparganium minimum (Hartm.) Fr.)

Greater Duckweed (Spirodela polyrhiza (L.) Schleid.)

Hooded Ladies'-tresses (Spiranthes romanzoffiana Cham.)

Seaside Arrow-grass (Triglochin maritimum L.)

Narrow-leaf Cattail (Typha angustifolia L.)

Broad-leaf Cattail (Typha latifolia L.)

Wild-Celery (Vallisneria americana Michx.)

California False-hellebore (Veratrum californicum E.M. Durand)

Horned Pondweed (Zannichellia palustris L.)

Speckled Alder (Alnus incana (L.) Moench)

Thin-leaf Alder (Alnus tenuifolia Nutt.)

Sticky False-willow (Baccharis glutinosa Pers.)

Tundra Dwarf Birch (Betula glandulosa Michx.)

Spring Birch (Betula occidentalis Hook.)

Alpine Bog Laurel (Kalmia microphylla (Hook.) A. Heller)

Pale Laurel (Kalmia polifolia Wangenh.)

Glandular Labrador-tea (Ledum glandulosum Nutt.)

Thicket Creeper (Parthenocissus vitacea (Knerr) A. Hitchc.)

Narrow-leaf Cotton-wood (Populus angustifolia E. James)

Hudson Bay Currant (Ribes hudsonianum Richards.)

White-stem Gooseberry (Ribes inerme Rydb.)

Peach-leaf Willow (Salix amygdaloides Anderss.)

Pacific Willow (Salix lasiandra Benth.)

Arroyo Willow (Salix lasiolepis Benth.)

Lemon's Willow (Salix lemmonii Bebb)

Diamond-leaf Willow (Salix planifolia Pursh)

Blue Elder (Sambucus cerulea Rat.)

Chinese Tamarisk (Tamarix chinensis Loureiro)

Saltcedar (Tamarix ramosissima Ledeb.)

Lyall's Angelica (Angelica arguta Nutt.)

Field Milkvetch (Astragalus agrestis Dougl. ex G. Don)

Canada Milkvetch (Astragalus canadensis L.)

American Winter-cress (Barbarea orthoceras Ledeb.)

Cut-leaf Water Parsnip (Berula erecta (Huds.) Coville)

Brewer's Bitter-cress (Cardamine breweri S. Wats.)

Few-seed Bitter-cress (Cardamine oligosperma Nutt.)

Western Water-hemlock (Cicuta douglasii (DC.) Coult. & Rose)

Poison-hemlock (Conium maculatum L.)

Sierra Corydalis (Corydalis caseana Gray)

Large-leaf Avens (Geum macrophyllum Wilid.)

American Licorice (Glycyrrhiza lepidota Pursh)

California Water-leaf (Hydrophyllum occidentale (S.Wats.) Gray)

Black Medic (Medicago lupulina L.)

White Sweetclover (Melilotus alba Medik.)

Buckbean (Menyanthes trifoliata L.)

Whorled Water-milfoil (Myriophyllum verticillatum L.)

Parrish's Yampah (Perideridia parishii (Coult. & Rose) A. Nels. & J.F. Macbr.)

Western Jacob's-ladder (Polemonium occidentale Greene)

Silverweed (Potentilla anserina L.)

Tall Cinquefoil (Potentilla arguta Pursh)

Varileaf Cinquefoil (Potentilla diversifolia Lehm.)

Gland Cinquefoil (Potentilla glandulosa Lindl.)

Northwest Cinquefoil (Potentilla gracilis Dougl. ex Hook.)

Marsh Cinquefoil (Potentilla palustris (L.) Scop.)

Platte Cinquefoil (Potentilla plattensis Nutt.)

White Water Butter-cup (Ranunculus aquatilis L.)

Yellow Water Butter-cup (Ranunculus flabellaris Raf.)

Small Yellow Water Butter-cup (Ranunculus gmelinii DC.)

Straight-beak Butter-cup (Ranunculus orthorhynchus Hook.)

Creeping Butter-cup (Ranunculus repens L.)

Pond Butter-cup (Ranunculus subrigidus W. B. Drew)

Curve-pod Yellow-cress (Rorippa curvisiliqua (Hook.) Bessey ex Britton)

Spreading Yellow-cress (Rorippa sinuata (Nutt.) A. Hitchc.)

Small Burnet (Sanguisorba minor Scop.)

Long-stalk Clover (Trifolium longipes Nutt.)

Large-head Clover (Trifolium macrocephalum (Pursh) Poir.)

Red Clover (Trifolium pratense L.)

Cows Clover (Trifolium wormskioldii Lehm.)

Lesser Bladderwort (Utricularia minor L.)

Western Valerian (Valeriana occidentalis A. Heller)

American Purple Vetch (Vicia americana Muhl. ex Willd.)

Streambank Arnica (Arnica amplexicaulis Nutt.)

Leafy Arnica (Arnica chamissonis Less.)

Sticky-leaf Arnica (Arnica diversifolia Greene)

Mountain Arnica (Arnica latifolia Bong.)

Seep Spring Arnica (Arnica longifolia D.C. Eat.)

Hairy Arnica (Arnica mollis Hook.)

Texas Bergia (Bergia texana (Hook.) Seub. ex Walpers)

Autumnal Water-starwort (Callitriche hermaphroditica L.)

Spiny Water-starwort (Callitriche verna L.)

Arizona Centaury (Centaurium calycosum (Buckley) Fernald)

Tall Centaury (Centaurium exaltatum (Griseb.) W. Wight ex Piper)

Chaffweed (Centunculus minimus L.)

Small Enchanter's Nightshade (Circaea alpina L.)

Glaucous Willow-herb (Epilobium glaberrimum Barbey)

Northern Bedstraw (Galium boreale L.)

Northern Gentian (Gentianella amare11a (L.) Boerner)

Rainier Pleated Gentian (Gentiana calycosa Griseb.)

Sea-milkwort (Glaux maritima L.)

Nuttall's Sunflower (Helianthus nuttallii Torr. & Gray)

Common Mare's-tail (Hippuris vulgaris L.)

Bog St. John's-wort (Hypericum anagalloides Cham. & Schlecht.)

Small-flower Sumpweed (Iva axillaris Pursh)

Marsh Felwort (Lomatogonium rotatum (L.) Fr. ex Fernald)

Northern Bugleweed (Lycopus uniflorus Michx.)

Scarlet Monkey-flower (Mimulus cardinalis Dougl. ex Benth.)

Common Large Monkey-flower (Mimulus guttatus DC.)

Suksdorf's Monkey-flower (Mimulus suksdorfii Gray)

Wild Bergamot (Monarda fistulosa L.)

Chamisso's Miner's-lettuce (Montia chamissoi (Ledeb. ex Spreng.) Greene)

Western Borax-weed (Nitrophila occidentalis (Moq.) S. Wats.)

Arctic Pearlwort (Sagina saginoides (L.) Karst.)

Red Saltwort (Salicornia rubra A. Nels.)

Long-leaf Starwort (Stellaria longifolia Muhl. ex Willd.)

Long-stalk Starwort (Stellaria longipes Goldie)

Umbellate Starwort (Stellaria umbellata Turcz. ex Karel. & Kir.)

American Speedwell (Veronica americana Schweinitz ex Benth.)

Water Speedwell (Veronica anagallis-aquatica L.)

American Alpine Speedwell (Veronica wormskjoldii Roem. & J.A. Schultes)

Columbia Monkshood (Aconitum columbianum Nutt.)

Orange-flower False-dandelion (Agoseris aurantiaca (Hook.) Greene)

California Amaranth (Amaranthus californicus (Moq.) S. Wats.)

Yerba Mansa (Anemopsis californica (Nutt.) Hook. & Arn.)

Flat-top Pussy-toes (Antennaria corymbosa E. Nels.)

Drummond's Rockcress (Arabis drummondii Gray)

Common California Aster (Aster chilensis Nees)

Siskiyou Aster (Aster hesperius Gray)

Five-horn Smother-weed (Bassia hyssopifolia (Pallas) Kuntze)

Slender-sepal Marsh-marigold (Caltha leptosepala DC.)

Heart-leaf Bitter-cress (Cardamine cordifolia Gray)

Scarlet Indian-paintbrush (Castilleja miniata Dougl. ex Hook.)

American Wormseed (Chenopodium ambrosioides L.)

Coast-blite Goosefoot (Chenopodium rubrum L.)

Creeping Thistle (Cirsium arvense (L.) Scop.)

Saltmarsh Bird's-beak (Cordylanthus maritimus Nutt. ex Benth.)

Brassbuttons (Cotula coronopifolia L.)

Dandelion Hawksbeard (Crepis runcinata (James) Torr. & Gray)

Spreading Alkali-weed (Cressa truxillensis HBK.)

Tower Larkspur (Delphinium glaucum S. Wats.)

Dark-throat Shooting-star (Dodecatheon pauciflorum Greene)

Few-flower Shooting-star (Dodecatheon pulchellum (Raf.) Merrill)

Double-horn Downingia (Downingia bicornuta Gray)

Great Basin Downingia (Downingia laeta (Greene) Greene)

Wandering Fleabane (Erigeron peregrinus (Banks ex Pursh) Greene)

Richardson's Crane's-bill (Geranium richardsonii Fisch. & Trautver.)

Lance-leaf Golden-weed (Haplopappus lanceolatus (Hook.) Torr. & Gray)

Seaside Heliotrope (Heliotropium curassavicum L.)

Streambank Wild-hollyhock (Iliamna rivularis (Dougl. ex Hook.) Greene)

Mexican Summer-cypress (Kochia scoparia (L.) Schrad.)

Northern Mudwort (Limosella aquatics L.)

Streamside Bluebells (Mertensia ciliata (E. James ex Torr.) G. Don)

Primrose Monkey-flower (Mimulus primuloides Benth.)

Five-point Bishop's-cap (Mitella pentandra Hook.)

Nuttall's Poverty-weed (Monolepis nuttalliana (J.A. Schultes) Greene)

Sedge Mouse-tail (Myosurus aristatus Benth. ex Hook.)

Hooker's Evening-primrose (Oenothera elata HBK.)

Yellow Evening-primrose (Oenothera flava (A. Nels.) Garrett)

Fringed Grass-of-Parnassus (Parnassia fimbriata K.D. Koenig)

Northern Grass-of-Parnassus (Parnassia palustris L.)

Elephant's-head Lousewort (Pedicularis groenlandica Retz.)

Arrow-leaf Sweet Coltsfoot (Petasites sagittatus (Banks ex Pursh) Gray)

Wedge-leaf Frog-fruit (Phyla cuneifolia (Torr.) Greene)

Scouter Popcorn-flower (Plagiabothrys scouleri (Hook. & Arn.) I. Johnst.)

Common Plantain (Plantago major L.)

Arrow-weed (Pluchea sericea (Nutt.) Coville)

American Bistort (Polygonum bistortoides Pursh)

Willow-weed (Polygonum lapathifolium L.)

Lady's Thumb (Polygonum persicaria L.)

Dotted Smartweed (Polygonum punctatum Elliott)

Viviparous Knotweed (Polygonum viviparum L.)

American Primrose (Primula incana M.E. Jones)

Subalpine Butter-cup (Ranunculus abortivus L.)

Dwarf Butter-cup (Ranunculus alismifolius Geyer ex Benth.)

Seaside Butter-cup (Ranunculus cymbalaria Pursh)

Eschscholtz Butter-cup (Ranunculus eschscholtzii Schlecht.)

Spearwort Butter-cup (Ranunculus flammula L.)

Sagebrush Butter-cup (Ranunculus glaberrimus Hook.)

Pennsylvania Butter-cup (Ranunculus pensylvanicus L. f.)

Sheep Sorrel (Rumex acetosella L.)

Golden Dock (Rumex maritimus L.)

Western Dock (Rumex occidentalis S. Wats.)

Brook Saxifrage (Saxifraga arguta D. Don)

Water Groundsel (Senecio hydrophilus Nutt.)

Arrow-leaf Groundsel (Senecio triangularis Hook.)

New Mexico Checker-mallow (Sidalcea neomexicana Gray)

Oregon Checker-mallow (Sidalcea oregana (Nuts. ex Torr. & Gray) Gray)

Pursh Seepweed (Suaeda depressa (Pursh) S. Wats.)

Western Seepweed (Suaeda occidentalis S. Wats.)

American Globeflower (Trollius laxus Salisb.)

Small White Violet (Viola macloskeyi Lloyd)

Northern Bog Violet (Viola nephrophylla Greene)