Index of Species Information

SPECIES:  Equisetum arvense


SPECIES: Equisetum arvense
AUTHORSHIP AND CITATION : Sullivan, Janet. 1993. Equisetum arvense. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: [].
ABBREVIATION : EQUARV SYNONYMS : Equisetum arvense var. alpestre Wahlenb. E. a. var. boreale (Bong.) Rupr. E. a. var. riparium Farw. E. calderi Boivin SCS PLANT CODE : EQAR COMMON NAMES : field horsetail common horsetail horsetail bottlebrush foxtail queue de renard pinetop jointed rush horse pipes mare's tail snake grass TAXONOMY : The accepted scientific name for field horsetail is Equisetum arvense L. Fernald [19] listed E. a. var. boreale (Bong.) Ledeb., a northern variety. There are a number of named forms that are not accepted by most authors as true forms; they may be growth variants that depend on environmental conditions and are not sufficiently distinct to warrant taxonomic recognition [9,69]. Field horsetail and water horsetail (E. fluviatale) will hybridize de novo where they occur together. The product, E. x litorale Kuhlewein is sterile, but vegetatively vigorous and persistent [23]. LIFE FORM : Fern or Fern Ally FEDERAL LEGAL STATUS : No special status OTHER STATUS : NO-ENTRY


SPECIES: Equisetum arvense
GENERAL DISTRIBUTION : Field horsetail is cosmopolitan in distribution.  In North America it occurs from Newfoundland west to Alaska and south to Georgia, Alabama, Texas, and California [19,23,25]. ECOSYSTEMS :    FRES10  White - red - jack pine    FRES11  Spruce - fir    FRES12  Longleaf - slash pine    FRES13  Loblolly - shortleaf pine    FRES14  Oak - pine    FRES15  Oak - hickory    FRES16  Oak - gum - cypress    FRES17  Elm - ash - cottonwood    FRES18  Maple - beech - birch    FRES19  Aspen - birch    FRES20  Douglas-fir    FRES21  Ponderosa pine    FRES22  Western white pine    FRES23  Fir - spruce    FRES24  Hemlock - Sitka spruce    FRES25  Larch    FRES26  Lodgepole pine    FRES27  Redwood    FRES28  Western hardwoods    FRES36  Mountain grasslands    FRES37  Mountain meadows    FRES38  Plains grasslands    FRES39  Prairie    FRES41  Wet grasslands STATES :      AL  AK  AZ  AR  CA  CO  CT  DE  GA  HI      ID  IN  IA  KS  KY  LA  ME  MD  MA  MI      MN  MS  MO  MT  NE  NV  NH  NJ  NY  NC      ND  OH  OK  OR  PA  RI  SC  SD  TN  TX      UT  VT  VA  WA  WV  WI  WY  AB  BC  MB      NB  NF  NT  NS  ON  PE  PQ  SK  YT BLM PHYSIOGRAPHIC REGIONS :     1  Northern Pacific Border     2  Cascade Mountains     3  Southern Pacific Border     4  Sierra Mountains     5  Columbia Plateau     6  Upper Basin and Range     7  Lower Basin and Range     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 :    K001  Spruce - cedar - hemlock forest    K002  Cedar - hemlock - Douglas-fir forest    K003  Silver fir - Douglas-fir forest    K004  Fir - hemlock forest    K005  Mixed conifer forest    K006  Redwood forest    K007  Red fir forest    K008  Lodgepole pine - subalpine forest    K009  Pine - cypress forest    K010  Ponderosa shrub forest    K011  Western ponderosa forest    K012  Douglas-fir forest    K013  Cedar - hemlock - pine forest    K014  Grand fir - 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    K022  Great Basin pine forest    K025  Alder - ash forest    K026  Oregon oakwoods    K028  Mosaic of K002 and K026    K029  California mixed evergreen forest    K030  California oakwoods    K036  Mosaic of K030 and K035    K046  Desert: vegetation largely lacking    K047  Fescue - oatgrass    K048  California steppe    K049  Tule marshes    K050  Fescue - wheatgrass    K051  Wheatgrass - bluegrass    K052  Alpine meadows and barren    K053  Grama - galleta steppe    K054  Grama - tobosa prairie    K057  Galleta - three-awn shrubsteppe    K063  Foothills prairie    K064  Grama - needlegrass - wheatgrass    K065  Grama - buffalograss    K066  Wheatgrass - needlegrass    K067  Wheatgrass - bluestem - needlegrass    K068  Wheatgrass - grama - buffalograss    K069  Bluestem - grama prairie    K070  Sandsage - bluestem prairie    K072  Sea oats prairie    K073  Northern cordgrass prairie    K074  Bluestem prairie    K075  Nebraska Sandhills prairie    K076  Blackland prairie    K077  Bluestem - sacahuista prairie    K078  Southern cordgrass prairie    K079  Palmetto prairie    K080  Marl - everglades    K081  Oak savanna    K082  Mosaic of K074 and K100    K083  Cedar glades    K084  Cross Timbers    K085  Mesquite - buffalograss    K088  Fayette prairie    K089  Black Belt    K092  Everglades    K093  Great Lakes spruce - fir forest    K094  Conifer bog    K095  Great Lakes pine forest    K096  Northeastern spruce - fir forest    K097  Southeastern spruce - fir forest    K098  Northern floodplain forest    K099  Maple - basswood forest    K100  Oak - hickory forest    K101  Elm - ash forest    K102  Beech - maple forest    K103  Mixed mesophytic forest    K104  Appalachian oak forest    K106  Northern hardwoods    K107  Northern hardwoods - fir forest    K108  Northern hardwoods - spruce forest    K109  Transition between K104 and K106    K110  Northeastern oak - pine forest    K111  Oak - hickory - pine forest    K112  Southern mixed forest    K113  Southern floodplain forest    K114  Pocosin    K115  Sand pine scrub    K116  Subtropical pine forest SAF COVER TYPES :      1  Jack pine      5  Balsam fir     12  Black spruce     13  Black spruce - tamarack     14  Northern pin oak     15  Red pine     16  Aspen     17  Pin cherry     18  Paper birch     19  Gray birch - red maple     20  White pine - northern red oak - red maple     21  Eastern white pine     22  White pine - hemlock     23  Eastern hemlock     24  Hemlock - yellow birch     25  Sugar maple - beech - yellow birch     26  Sugar maple - basswood     27  Sugar maple     28  Black cherry - maple     30  Red spruce - yellow birch     31  Red spruce - sugar maple - beech     32  Red spruce     33  Red spruce - balsam fir     34  Red spruce - Fraser fir     35  Paper birch - red spruce - balsam fir     37  Northern white-cedar     38  Tamarack     39  Black ash - American elm - red maple     40  Post oak - blackjack oak     42  Bur oak     43  Bear oak     44  Chestnut oak     45  Pitch pine     46  Eastern redcedar     50  Black locust     51  White pine - chestnut oak     52  White oak - black oak - northern red oak     53  White oak     55  Northern red oak     57  Yellow-poplar     58  Yellow-poplar - eastern hemlock     59  Yellow-poplar - white oak - northern red oak     60  Beech - sugar maple     61  River birch - sycamore     62  Silver maple - American elm     63  Cottonwood     64  Sassafras - persimmon     65  Pin oak - sweetgum     69  Sand pine     70  Longleaf pine     71  Longleaf pine - scrub oak     72  Southern scrub oak     73  Southern redcedar     74  Cabbage palmetto     75  Shortleaf pine     76  Shortleaf pine - oak     78  Virginia pine - oak     79  Virginia pine     80  Loblolly pine - shortleaf pine     81  Loblolly pine     82  Loblolly pine - hardwood     83  Longleaf pine - slash pine     84  Slash pine     85  Slash pine - hardwood     87  Sweet gum - yellow-poplar     88  Willow oak - water oak - diamondleaf oak     89  Live oak     91  Swamp chestnut oak - cherrybark oak     92  Sweetgum - willow oak     93  Sugarberry - American elm - green ash     94  Sycamore - sweetgum - American elm     95  Black willow     96  Overcup oak - water hickory     97  Atlantic white-cedar     98  Pond pine    100  Pondcypress    101  Baldcypress    102  Baldcypress - tupelo    103  Water tupelo - swamp tupelo    104  Sweetbay - swamp tupelo - redbay    107  White spruce    108  Red maple    109  Hawthorn    110  Black oak    111  South Florida slash pine    201  White spruce    202  White spruce - paper birch    203  Balsam poplar    204  Black spruce    205  Mountain hemlock    206  Engelmann spruce - subalpine fir    207  Red fir    208  Whitebark pine    209  Bristlecone pine    210  Interior Douglas-fir    211  White fir    212  Western larch    213  Grand fir    215  Western white pine    216  Blue spruce    217  Aspen    218  Lodgepole pine    219  Limber pine    221  Red alder    222  Black cottonwood - willow    223  Sitka spruce    224  Western hemlock    225  Western hemlock - Sitka spruce    226  Coastal true fir - hemlock    227  Western redcedar - western hemlock    228  Western redcedar    229  Pacific Douglas-fir    230  Douglas-fir - western hemlock    231  Port-Orford-cedar    232  Redwood    233  Oregon white oak    234  Douglas-fir - tanoak - Pacific madrone    235  Cottonwood - willow    236  Bur oak    237  Interior ponderosa pine    243  Sierra Nevada mixed conifer    244  Pacific ponderosa pine - Douglas-fir    245  Pacific ponderosa pine    246  California black oak    247  Jeffrey pine    248  Knobcone pine    249  Canyon live oak    250  Blue oak - Digger pine    251  White spruce - aspen    252  Paper birch    253  Black spruce - white spruce    254  Black spruce -  paper birch    255  California coast live oak    256  California mixed subalpine SRM (RANGELAND) COVER TYPES : NO-ENTRY HABITAT TYPES AND PLANT COMMUNITIES : Field horsetail is abundant in many spruce communities, including white spruce (Picea glauca), black spruce (P. mariana), blue spruce (P. pungens), and Engelmann spruce (P. engelmannii).  In Alberta and British Columbia, other common understory species in the white spruce communities in which field horsetail is abundant include prickly rose (Rosa acicularis), honeysuckle (Lonicera involucrata), bunchberry (Cornus canadensis), twinflower (Linnea borealis), naked miterwort (Mitella nuda), and mountain fern moss (Hylocomium splendens) [1]. Field horsetail is a common indicator or herbaceous layer dominant for mesic, hygric, and subhygric sites [3,26,40].  It occurs or is an herbaceous layer dominant in a number of riparian associations, with overstories of spruce, cottonwood (Populus spp.), willow (Salix spp.), paper birch (Betula papyrifera), or alder (Alnus spp.) [3,30,44]. Field horsetail occasionally dominates sites lacking a woody overstory; such sites are usually adjacent to a forest or shrub community [27].  In Alberta field horsetail dominates low shores of channels and lakes with water horsetail, water sedge (Carex aquatilis), and pendent grass (Artophila fulva) [47]. A selection of publications naming field horsetail as an indicator or herbaceous layer dominant is as follows: Old growth forests of the Canadian Rocky Mountain national parks [1] Classification of the riparian vegetation of the montane and subalpine    zones in western Colorado [3] Forest community types of west-central Alberta in relation to selected    environmental factors [10] Classification and management of riparian and wetland sites in central    and eastern Montana [26] Riparian dominance types of Montana [27] Habitat types on selected parts of the Gunnison and Uncompahgre         National Forests [38] Riparian zone associations: Deschutes, Ochoco, Fremont, and Winema      National Forests [39] Coniferous forest habitat types of northern Utah [48] Wetland community type classification for west-central Montana [70] Forest habitat types of Montana [53] Vegetation and soils along the Dempster Highway, Yukon Territory:    I. Vegetation types [57] Forest habitat types of eastern Idaho-western Wyoming [71] A riparian community classification study [67] Riparian community type classification of eastern Idaho-western    Wyoming [68]


SPECIES: Equisetum arvense
IMPORTANCE TO LIVESTOCK AND WILDLIFE : Field horsetail is a common food item consumed by grizzly bears [37]. On average, field horsetail formed 2.4 to 5.2 percent by volume of the grizzly bear summer diet in Yellowstone National Park and was ranked 10th out of 32 food items in amount of consumption [49].  Field horsetail occurs in the wet meadows, marshes and moist cirque basins most often visited by grizzly bears in spring [2].  Field horsetail is a minor to important component in the spring and early summer diet of black bears [28,32].  It is of low nutritive value [49]. Field horsetail is not an important range forage for livestock, and excessive amounts (more than 20 percent) in hay can cause scours, paralysis, and death in horses [36]. PALATABILITY : Field horsetail is low in palatability to livestock, deer, and elk [39]. NUTRITIONAL VALUE : The nutritive value of the sterile shoots of field horsetail, as percentage of dry weight, is as follows [49]: protein                  15 nitrogen-free extract    40.6 ether extract             3.7 gross kilocalories        2.9 per gram Aerial, fresh field horsetail nutritive components, as percentage of dry weight, are as follows [50]: dry matter                    100 ash                            18.5 crude fiber                    23.5 ether extract                   2.4 nitrogen free extract          50.3 protein (nitrogen x 6.25)       5.3 digestible protein for    cattle                       2.4    goats                        1.5    horses                       2.0    rabbits                      2.8    sheep                        1.9 COVER VALUE : Field horsetail provides poor to fair cover for wildlife [13]. VALUE FOR REHABILITATION OF DISTURBED SITES : NO-ENTRY OTHER USES AND VALUES : Native Americans and early settlers used tea made from field horsetail as a diuretic.  Field horsetail was used as a cough medicine for horses. Dyes for clothing, lodges, and porcupine quills were made from field horsetail.  It was used for scouring and polishing objects.  The young shoots were eaten either cooked or raw [40]. Silica extracted from field horsetail is utilized for manufacture of remineralizing and diuretic medicinal products.  Other potential uses of biogenic silica include industrial applications (abrasives, toothpaste, protective cloth, optical fibers, thickeners for paint, etc.), detergents, and cleaners.  Leaf-odor constituents were used widely in th 1970's in perfumes but are little used now.  These constituents can be used as food flavors and flavor enhancers, and as animal repellants [63]. OTHER MANAGEMENT CONSIDERATIONS : Field horsetail is a weed in more than 25 crops of the world but is seldom the worst offender.  It is probably toxic to surrounding vegetation due to high levels of alkaloids [33].  Field horsetail increases after soil cultivation with or without the application of herbicides [8].  It may be at least partially controlled by some herbicides [51]. Field horsetail is sensitive to moisture stress; drought conditions result in a reduction in the production of new shoots [8]. Repeated cultivation by hoeing reduces the number of mature shoots per acre [8].  It is recommended that agricultural land infested with field horsetail be deep-plowed each season to prevent deep rhizome development; however, this will probably not be successful if the rhizomes have already penetrated below plow-depth [33].


SPECIES: Equisetum arvense
GENERAL BOTANICAL CHARACTERISTICS : Field horsetail is a native, perennial, rhizomatous cryptogam.  The sporophyte is dimorphic with unbranched, fertile (stroboliferous), spore-producing stems and branched, sterile stems.  The spores germinate to produce a distinct gametophytic generation.  The prothallus (gametophyte) is tiny, from 0.002 to 0.008 inch (0.5-2.0 mm) in height (occasionally up to 0.016 inch [4 mm] in the center) and irregularly lobed or branched [4,14]. The sterile stems are jointed, hollow, usually erect, and bear up to 20 whorls of slender branches [9].  They are usually from 2 to 24 inches (5-60 cm) tall, rarely to 40 inches (1 m) tall [25].  The inconspicuous, scalelike leaves occur in whorls at the nodes and are connected at their bases.  The fertile stems are nonchlorophyllous and generally are from 2 to 12 inches (5-30 cm) tall [19,25].  The strobili are from 0.4 to 1.4 inches (1-3.5 cm) long, peduncled, and blunt.  The epidermis of both types of stems has regularly arranged, silicified projections [23]. The rhizomes of field horsetail are branched and creeping.  They are similar to the aerial stems except that they are not hollow [9]. Storage tubers are produced on the rhizomes [19].  The rhizomes extend to a depth of 40 inches (100 cm) or more; 50 percent of the total rhizome weight is in the top 10 inches (25 cm) of soil, 23 percent in the next 9.2 inches (23 cm), and the rest deeper [65].  Successive, layered horizontal rhizome systems occur at about 12-inch (30 cm) intervals.  Golub and Wetmore [24] found five such layers by digging to a 6.6 foot (2 m) depth, noting that the system extended even deeper. Root development takes place at the bases of lateral branch buds, both on rhizomes and erect shoots [33]. RAUNKIAER LIFE FORM :       Geophyte REGENERATION PROCESSES : The main mode of reproduction of field horsetail is asexual; conditions for the production of gametophytes from spores are limited and relatively rare [14,45]. Asexual reproduction:  Field horsetail spreads from extensive rhizomes. Even short segments of broken rhizomes (1.2 inches [3 cm]) will sprout [8].  Overwintering buds develop at the nodes of the rhizomes [29]. Sexual reproduction:  The spores of field horsetail are equipped with elaters, which are long appendages that expand and contract with changes in humidity.  Elaters function to dig the spore into the soil surface and to tangle spores together, thereby creating a larger propagule and increasing the probability that prothalli will be close enough to ensure fertilization.  Elaters may also aid in wind dissemination.  Spores released by the strobiliferous stems are dispersed by wind or water. The spores are thin-walled, short-lived, and quickly germinate under moist conditions [31].  The spores germinate to form prothalli:  tiny plants only a few cell layers thick that are usually either male or female, producing only antheridia or archegonia, respectively.  Swimming sperm are released by the antheridia and require water for transport to the egg-containing archegonia.  After fertilization takes place, the sporophytic generation (the identifiable large plant) develops in situ, growing out of the prothallus. SITE CHARACTERISTICS : Field horsetail is a facultative wetland species [27].  Field horsetail occurs in woods, fields, meadows and swamps, and moist soils alongside streams, rivers, and lakes, and in disturbed areas [9,25].  Field horsetail usually occurs on moist sites but can also be found on dry and barren sites such as roadsides, borrow pits, and railway embankments [9,35].  Under suitably moist climatic conditions, gametophytes occur on newly deposited mud flats and gravel banks of rivers and lakes [14]. In the Adirondack Mountains of New York, field horsetail occurs from 210 to 2,100 feet (64-640 m) in elevation [42].  In Alaska, field horsetail is widely distributed from sea level to alpine communities.  On alpine sites it is found on heaths, moist meadows, and rocky slopes [56]. Field horsetail is found at a wide range of elevations.  Elevational distributions from selected western states are as follows [13]: Utah          4,700 to  8,000 feet (1,400-2,400 m) Colorado      5,100 to 10,800 feet (1,500-3,290 m) Wyoming       4,900 to  9,700 feet (1,500-3,000 m) Montana       2,900 to  4,600 feet (  880-1,400 m) SUCCESSIONAL STATUS : Facultative Seral Species Field horsetail is present in both seral and climax communities; its presence is largely dictated by edaphic conditions rather than shade or other factors.  Field horsetail is an early colonizer on floodplain deposits.  These communities are often destroyed by flooding before beingcan stabilized by willow establishment [62].  Field horsetail continues to be present through succession, occurring under more developed willow-alder communities, as an herbaceous layer dominant with meadow horsetail (Equisetum pratense) under open balsam poplar (Populus balsamifera)/thinleaf alder (Alnus tenuifolia) stands, and in the herbaceous layer of closed balsam poplar/white spruce communities [62]. Field horsetail is an early colonizer of moist, primary successional sites created by glacial retreat [59].  It is among the most common and abundant sprouter in areas disturbed by debris from drilling activity in northern Alaska.  In most of these areas, field horsetail sprouted from rhizomes already present under the debris [17].  Logging or logging and burning may either maintain or increase field horsetail cover, depending on pretreatment levels and forest cover type [12,15]. SEASONAL DEVELOPMENT : Strobiliferous shoot buds are initiated in July, August and into September.  Vegetative buds are initiated in October and November. Strobiliferous buds elongate early in spring (March to May, depending on latitude), usually before the vegetative stems elongate [29].  Emergence is earliest in dry sandy places, later in wet or clay soils [9].  Spores are shed in early May in the Adirondack Mountains of New York [42].  The strobiliferous shoots die after the spores are shed [4].  Sterile stems emerge in May, producing branches after they are 3 to 5 inches (8-12 cm) in height [9,33]. Stems are killed by hard frost but may live into winter in areas where they are protected [9].  Gametophytes are killed by frost; they do not live longer than one growing season [14].


SPECIES: Equisetum arvense
FIRE ECOLOGY OR ADAPTATIONS : Field horsetail usually occurs in moist habitats that do not undergo frequent fire.  For example, in Idaho and Montana, it occurs in Fire Group 11 stands (as described by Bradley and others), which have a fire-return interval of 325 to 335 years (plus or minus 50 years).  When fires do occur, however, they are often severe due to high fuel loads. Field horsetail is adapted to survive such fires; it has deep rhizomes that are not killed by even very hot fires [52].  Field horsetail also colonizes disturbed areas or new sites by wind-disseminated propagules, although this is probably rare [7]. POSTFIRE REGENERATION STRATEGY :    Rhizomatous herb, rhizome in soil    Geophyte, growing points deep in soil    Ground residual colonizer (on-site, initial community)    Initial-offsite colonizer (off-site, initial community)


SPECIES: Equisetum arvense
IMMEDIATE FIRE EFFECT ON PLANT : Field horsetail is top-killed by most fires.  The rhizomes are particularly resistant to fire because they are buried deep in the mineral soil [39]. DISCUSSION AND QUALIFICATION OF FIRE EFFECT : NO-ENTRY PLANT RESPONSE TO FIRE : Field horsetail regenerates rapidly after a fire [40].  The frequency of occurrence of field horsetail is usually unchanged or increased after fire.  Gametophyte establishment requires the presence of moist, exposed mineral soils (as well as a source of spores) [7]. In the first summer following a late May, 1983, wildfire in white spruce stands, a number of herbaceous species established from seed.  These included Bicknell geranium (Geranium bicknellii), Corydalis sempervirens, false dragonhead (Dracocephalum parviflorum), and fireweed.  By 1985, they were replaced by more persistent species including field horsetail and bluejoint reedgrass (Calamagrostis canadensis) [61]. In newly burned white spruce sites, field horsetail occurred in most stands within weeks of the fire and gradually increased through postfire succession.  Field horsetail is dominant in the herbaceous layer by 46 to 150 years after fire and persists into the climax stage (300 or more years) [15,21]. DISCUSSION AND QUALIFICATION OF PLANT RESPONSE : Hamilton's Research Papers (Hamilton 2006a, Hamilton 2006b) provide information on prescribed fire and postfire response of many plant species, including field horsetail, that was not available when this species review was originally written. FIRE MANAGEMENT CONSIDERATIONS : NO-ENTRY

References for species: Equisetum arvense

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3. Baker, William L. 1989. Classification of the riparian vegetation of the montane and subalpine zones in western Colorado. The Great Basin Naturalist. 49(2): 214-228. [7985]
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7. Bradley, Anne F.; Noste, Nonan V.; Fischer, William C. 1992. Fire ecology of forests and woodlands in Utah. Gen. Tech. Rep. INT-287. Ogden, UT: U.S. Department of Agriculture, Forest Service, Intermountain Research Station. 128 p. [18700]
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16. Dyrness, C. T.; Viereck, L. A.; Van Cleve, K. 1986. Fire in taiga communities of interior Alaska. In: Forest ecosystems in the Alaskan taiga. New York: Springer-Verlag: 74-86. [3881]
17. Ebersole, James J. 1987. Short-term vegetation recovery at an Alaskan arctic coastal plain site. Arctic and Alpine Research. 19(4): 442-450. [9476]
18. Eyre, F. H., ed. 1980. Forest cover types of the United States and Canada. Washington, DC: Society of American Foresters. 148 p. [905]
19. Fernald, Merritt Lyndon. 1950. Gray's manual of botany. [Corrections supplied by R. C. Rollins]. Portland, OR: Dioscorides Press. 1632 p. (Dudley, Theodore R., gen. ed.; Biosystematics, Floristic & Phylogeny Series; vol. 2) [14935]
20. Foote, Geoffrey G. 1965. Phytosociology of the bottomland hardwood forests in western Montana. Missoula, MT: Univeristy of Montana. 140 p. Thesis. [17369]
21. Foote, M. Joan. 1983. Classification, description, and dynamics of plant communities after fire in the taiga of interior Alaska. Res. Pap. PNW-307. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Forest and Range Experiment Station. 108 p. [7080]
22. Garrison, George A.; Bjugstad, Ardell J.; Duncan, Don A.; [and others]. 1977. Vegetation and environmental features of forest and range ecosystems. Agric. Handb. 475. Washington, DC: U.S. Department of Agriculture, Forest Service. 68 p. [998]
23. Gleason, Henry A.; Cronquist, Arthur. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. 2nd ed. New York: New York Botanical Garden. 910 p. [20329]
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