Humboldt State University Digital Commons @ Humboldt State University Botanical Studies Open Educational Resources and Data 4-2019 Vascular Plants of Horse Mountain (Humboldt County, California) James P. Smith Jr Humboldt State University, [email protected] John O. Sawyer Jr. Humboldt State University Follow this and additional works at: https://digitalcommons.humboldt.edu/botany_jps Part of the Botany Commons Recommended Citation Smith, James P. Jr and Sawyer, John O. Jr., "Vascular Plants of Horse Mountain (Humboldt County, California)" (2019). Botanical Studies. 38. https://digitalcommons.humboldt.edu/botany_jps/38 This Flora of Northwest California: Checklists of Local Sites of Botanical Interest is brought to you for free and open access by the Open Educational Resources and Data at Digital Commons @ Humboldt State University. It has been accepted for inclusion in Botanical Studies by an authorized administrator of Digital Commons @ Humboldt State University. For more information, please contact [email protected]. VASCULAR PLANTS OF HORSE MOUNTAIN (HUMBOLDT COUNTY, CALIFORNIA) Compiled by James P. Smith, Jr. & John O. Sawyer, Jr. Department of Biological Sciences Humboldt State University Arcata, California Fourth Edition · 29 April 2019 Horse Mountain (elevation 4952 ft.) is located at 40.8743N, -123.7328 W. The Polystichum x scopulinum · Bristle or holly fern closest town is Willow Creek, about 15 miles to the northeast. Access is via County Road 1 (Titlow Hill Road) off State Route 299. You have now left the Coast Range PTERIDACEAE BRAKE FERN FAMILY and entered the Klamath-Siskiyou Region. The area offers commanding views of Adiantum pedatum var. aleuticum · Maidenhair fern the Pacific Ocean and the Trinity Alps. Serpentine (ultramafic rock) is a common Aspidotis densa · Indian’s dream substrate. About 1100 acres, ranging from 3900-4800 ft., have been set aside as Cheilanthes gracillima · Lace fern the Horse Mountain Botanical Area, administered by the Six Rivers National Cryptogramma achrostichoides · Parsley fern Forest. SELAGINELLACEAE Mine tailings, remnants of a processing facility, and scattered pits are reminders of Selaginella wallacei · Wallace’s spike-moss Horse Mountain’s mining history. The peak itself is now the home of various of communication towers. CONIFERS FERNS & LYCOPHYTES CUPRESSACEAE · CYPRESS FAMILY Calocedrus decurrens · Incense-cedar ATHYRIACEAE · LADY FERN FAMILY Chamaecyparis lawsoniana · Port Orford-cedar Athyrium filix-femina · Lady fern PINACEAE · PINE FAMILY DENNSTAEDTIACEAE · BRACKEN FERN FAMILY Abies concolor x A. grandis · White fir - grand fir hybrid Pteridium aquilinum var. pubescens · Bracken fern Abies grandis · Grand fir Pinus attenuata · Knobcone pine DRYOPTERIDACEAE · HOLLY FERN FAMILY Pinus jeffreyi · Jeffrey pine Polystichum imbricans ssp. imbricans · Narrow-leaved sword fern Pinus lambertiana · Sugar pine Polystichum munitum · Western sword fern Pinus monticola · Western white pine Pinus ponderosa var. pacifica · Ponderosa pine Pseudotsuga menziesii · Douglas-fir AMARYLLIDACEAE · AMARYLLIS OR ONION FAMILY Allium falcifolium · Scythe-leaved onion FLOWERING PLANTS Allium siskiyouense · Siskiyou onion ACERACEAE · MAPLE FAMILY ASPARAGACEAE · HYACINTH OR ASPARAGUS FAMILY Acer glabrum var. glabrum · Mountain maple Brodiaea elegans ssp. elegans · Harvest brodiaea Acer macrophyllum · Big-leaf maple Dichelostemma capitatum ssp. capitatum · Blue dicks −1− Hastingsia alba · white rush-lily Symphoricarpos mollis · Creeping snowberry Hastingsia serpentinicola · Serpentine rush-lily Maianthemum racemosum · False lily-of-the-valley CARYOPHYLLACEAE · PINK FAMILY Triteleia laxa · Ithuriel’s spear · Arenaria macrophylla · Big-leaved sandwort Minuartia nuttallii ssp. gregaria · Nuttall’s sandwort APOCYNACEAE · DOGBANE FAMILY Moehringia macrophylla · Large-leaved sandwort Apocynum androsaemifolium · Mountain-hemp Pseudostellaria jamesiana · Sticky sandwort Silene californica · California Indian pink ARALIACEAE · ARALIA OR SPIKENARD FAMILY Silene campanulata ssp. glandulosa · Mountain catchfly Aralia californica · California spikenard Silene laciniata ssp. californica · California Indian pink Stellaria nitens · Shiny chickweed ARISTOLOCHIACEAE · DUTCHMAN’S PIPE FAMILY Asarum caudatum · Long-tailed wild ginger COLCHICACEAE · AUTUMN CROCUS FAMILY Asarum hartwegii · Hartweg’s wild ginger Prosartes hookeri · Fairy bells BERBERIDACEAE · BARBERRY FAMILY COMPOSITAE · SUNFLOWER FAMILY Achlys triphylla · Vanilla leaf Achillea millefolium · Yarrow Mahonia aquifolium · Oregon-grape Agoseris heterophylla var. heterophylla · Annual agoseris Mahonia nervosa · Oregon-grape Antennaria luzuloides · Woodrush pussytoes Vancouveria planipetala · Inside-out flower Antennaria suffrutescens · Evergreen pusseytoes Arnica cernua · Nodding arnica BETULACEAE · BIRCH FAMILY Arnica discoidea · Rayless arnica Corylus cornuta var. californica · California hazel nut Brickellia greenei · Greene’s tassel flower Chaenactis douglasii var. douglasii · Hoary chaenactis Cirsium arvense · Canada thistle BORAGINACEAE · BORAGE FAMILY Cirsium cymosum var. cymosum · Peregrine thistle Cryptantha torreyana · Torrey’s cat’s-eye Cirsium douglasii var. breweri · Brewer’s thistle Cirsium douglasii var. douglasii · Douglas’ thistle CAMPANULACEAE · BELLFLOWER FAMILY Cirsium occidentale var. venustum · Cobwebby thistle Asyneuma prenanthoides · California harebell Crepis acuminata · Long-leaved hawk’s-beard Campanula scouleri · Scouler’s harebell Crepis pleurocarpa · Naked-stemmed hawk’s-beard Ericameria nauseosa var. speciosa · Rubber rabbit brush CAPRIFOLIACEAE · HONEYSUCKLE FAMILY Eriophyllum lanatum var. lanceolatum · Woolly-sunflower Hemizonella minima · Opposite-leaved tarweed Sedum laxum ssp. flavidum · Pale-yellow stonecrop Hieracium albiflorum · White-flowered hawkweed Sedum laxum ssp. heckneri · Heckner’s stonecrop Hieracium bolanderi · Bolander’s hawkweed Sedum laxum ssp. laxum · Rose-colored stonecrop Madia elegans · Common madia Sedum obtusatum · Sierran stonecrop Madia gracilis · Gumweed, slender tarweed Sedum radiatum ssp. radiatum · Star-fruited stonecrop Microseris laciniata ssp. leptosepala · Slender silverpuffs Sedum spathulifolium · Broad-leaved stonecrop Microseris nutans · Silverpuffs Symphyotrichum spathulatum · Western mountain-aster CRUCIFERAE · MUSTARD FAMILY Wyethia angustifolia · Narrow-leaved mule’s-ear Cardamine californica var. californica · California toothwort Wyethia longicaulis · Humboldt County mule’s-ear Cardamine nuttallii · Nuttall’s toothwort Erysimum capitatum · Douglas’ or western wallflower CONVOLVULACEAE · MORNING GLORY FAMILY Noccaea fendleri var. glaucum · Alpine pennycress Calystegia occidentalis ssp. occidentalis · Morning glory Streptanthus tortuosus · Mountain jewelflower CORNACEAE · DOGWOOD FAMILY CYPERACEAE · SEDGE FAMILY Cornus nuttallii · Nuttall’s dogwood Carex athrostachya · Slender-beaked sedge Carex concinnoides · Northwestern sedge CRASSULACEAE · STONECROP FAMILY Carex echinata · Star sedge −2− Carex geyeri · Elk sedge Carex mendocinensis · Mendocino sedge FAGACEAE · OAK OR BEECH FAMILY Carex multicostata · Many-ribbed sedge Chrysolepis chrysophylla · Chinquapin Carex ovalis · Egg-bracted sedge Notholithocarpus densiflorus var. densiflorus · Tanoak Carex serratodens · Two-toothed sedge Quercus chrysolepis var. chrysolepis · Canyon live oak Carex subfusca · Rusty sedge Quercus chrysolepis var. nana · Dwarf canyon live oak Eriophorum crinigerum · Fringed cotton-grass Quercus garryana var. garryana · Oregon white oak Quercus vacciniifolia · Huckleberry oak ERICACEAE · HEATH FAMILY Allotropa virgata · Sugar stick GARRYACEAE · SILK-TASSEL FAMILY Arbutus menziesii · Madrone Garrya buxifolia · Dwarf silk-tassel Arctostaphylos canescens ssp. sonomensis · Hoary manzanita Garrya elliptica · Coast silk-tassel Arctostaphylos canescens ssp. glandulosa · Eastwood’s manzanita Garrya fremontii · Fremont’s silk-tassel Arctostaphylos nevadensis var. nevadensis · Pinemat manzanita Arctostaphylos patula · Green-leaved manzanita GENTIANACEAE · GENTIAN FAMILY Chimaphila umbellata var. occidentalis · Western prince’s-pine Gentiana calycosa · Explorer’s gentian Gaultheria ovatifolia · Oregon spicy wintergreen Gaultheria shallon · Salal GRAMINEAE · GRASS FAMILY Pityopus californica · California pinefoot Agrostis oregonensis · Oregon redtop Pterospora andromedea · Pinedrops Bromus carinatus · California brome Pyrola picta · White-veined wintergreen Bromus tectorum · Downy brome, cheat grass Rhododendron occidentale · Western azalea Calamagrostis koelerioides · Tufted pine grass Vaccinium parvifolium · Red huckleberry Calamagrostis ophitidis · Serpentine reed grass Dactylis glomerata · Orchard grass Danthonia unispicata · One-spike oat grass HYDROPHYLLACEAE · WATERLEAF FAMILY Deschampsia elongata · Slender hair grass Hydrophyllum occidentale · California waterleaf Elymus glaucus · Blue wild-rye Nemophila menziesii · Baby blue-eyes Elymus x hansenii · Hansen’s squirreltail Phacelia corymbosa · Serpentine phacelia Elymus lanceolatus ssp. lanceolatus · Thick-spiked wild-rye Phacelia mutabilis · Changeable phacelia Elymus multisetus · Squirreltail Festuca californica ssp. californica · California fescue IRIDACEAE · IRIS FAMILY Festuca idahoensis · Idaho fescue Iris macrosiphon · Slender-tubed iris Festuca rubra · Red fescue Iris purdyi · Purdy’s iris Melica geyeri · Geyer’s onion grass Iris tenuissima ssp. tenuissima · Long-tubed iris Melica harfordii · Harford’s melic Sisyrinchium bellum · California