Equisetum arvense, field horsetail
Sullivan, Janet. 1993. Equisetum arvense, field horsetail. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://research.fs.usda.gov/feis/species-reviews/equarv
| Abbreviation | Common Name | Scientific Name | Classification | Status |
|---|---|---|---|---|
| Plants | ||||
| EQUARV | field horsetail | Equisetum arvense | Life Form: Plants/Fern or Fern Ally, Plants/Forb Kingdom: Plantae Class: Horsetail Order: Equisetales Family: Equisetaceae Genus: Equisetum | Fed. Protected: No Nativity: Native Invasiveness: Noninvasive |
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].
Synonyms
- Equisetum arvense var. alpestre Wahlenb.
- E. a. var. boreale (Bong.) Rupr.
- E. a. var. riparium Farw.
- E. calderi Boivin
Other Common Names
common horsetail, horsetail, bottlebrush, foxtail, horse pipes, jointed rush, mare's tail, pinetop, queue de renard, snake grass
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].
States and Provinces
- United 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
- Canada: AB BC MB NB NF NT NS ON PE PQ SK YT
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]:
| State | Elevational range |
|---|---|
| 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) |
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]
Botanical Description
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 (Raunkiaer 1934)
- Geophyte
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].
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.
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 being 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].
Immediate Fire Effects
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].
Postfire Regeneration Strategy (Stickney 1989)
- 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)
Fire 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].
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].
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 Regimes
For fire regime information, search FEIS for this species by entering the species name or acronym on the home page and selecting “Fire Regime” as the publication type.
Fire Management Considerations
No entry.
Federal Status
None
Other Status
No entry.
Importance to Wildlife and Livestock
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 and Nutritional Value
Field horsetail is low in palatability to livestock, deer, and elk [39]. The nutritive value of the sterile shoots of field horsetail are given by [49], and a breakdown of aerial, fresh field horsetail nutritive components is given by [50].
Cover Value
Field horsetail provides poor to fair cover for wildlife [13].
Value for Rehabilitation or Restoration of Disturbed Sites
No entry.
Other Uses
American Indians 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 the 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 may be 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].
Table A1— Forest and range ecosystems, Bureau of Land Management (BLM) physiographic regions, Kuchler plant associations, Society for American Foresters (SAF) forest cover types, and Society for Rangeland Management (SRM) rangeland cover types in which this species occurs.
Forest and Range Ecosystems (Garrison et al. 1977)
- Widely distributed, occurs in most types within its range.
BLM Physiographic Regions (Bernard and Brown 1977)
- Widely distributed, occurs in most physiographic regions.
Kuchler Plant Associations (Kuchler 1964)
- Widely distributed, occurs in most types within its range.
SAF Cover Types (Eyre 1980)
- Widely distributed, occurs in most types within its range.
SRM Rangeland Cover Types (Shiflet 1994)
- Widely distributed, occurs in most types within its range.
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