Equisetum arvense

This native perennial plant produces fertile and infertile shoots that are deciduous. Each fertile shoot is unbranched and about 4-6" tall. It has a central stalk that is light brown to brown and about ¼" across in diameter. This stalk terminates in a spore-bearing cone up to 1" long; the cone is oblongoid in shape and rounded at the top. The surface of the cone is mostly brown, but it is covered with spore-bearing tubercles that have black and white markings. The fertile shoots develop during mid-spring, but soon wither away after the cones have released their spores. The infertile (or vegetative) shoots have a very different appearance. They develop during late spring and persist until the fall. The infertile shoots are ½–2' tall; they have whorls of branchlets along at least the upper half of their stems. The stems and branchlets of these shoots are slender and green. Each central stem consists of several joints; at the apex of each joint (except the uppermost), there is a short sheath with 3-4 teeth along its upper rim. This sheath is appressed to slightly spreading and green to brown. The base of the next joint develops from this sheath. Each joint is terete with 10-14 ridges along its length; sometimes there are more or fewer ridges. Initially, the branchlets are similar to the central stems, except they are much smaller in size. Later, they become almost as long as the stems. At this stage, the infertile shoots resemble small conifers because of the long needle-like branchlets. The branchlets have joints with sheaths like the stems, but there are only 3-4 teeth along the upper rim of each sheath. Usually, these branchlets are unbranched, but sometimes they produce secondary branchlets. An infertile shoot may produce a small infertile cone at its apex, but this is very unusual. Both the stems and branchlets of Common Horsetail are mostly solid. The root system consists of long rhizomes and secondary fibrous roots. This plant often forms colonies.

This odd little plant is the most common and weedy horsetail in Illinois. The cone-bearing fertile shoots resemble brown mushrooms (something like the morel mushroom), while the infertile shoots look like small conifers during the summer. Few people realize that both types of shoots are produced from the rhizomes of the same plant. Common Horsetail differs from other horsetails by its brown fertile shoots, which lack chlorophyll. Other Equisetum spp. (Horsetails) in Illinois produce green fertile shoots that are similar to infertile shoots in appearance. The whorled branchlets of Common Horsetail can become almost as long as the central stem – they are produced in great abundance and often obscure the central stem's visibility by the beginning of summer. Other Horsetails produce branchlets that are much shorter than their stems, or they produce no branchlets at all. There are other technical differences between Common Horsetail and other Horsetails, but it is usually easy to identify in the field.

     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

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].

Common Horsetail is found in every county of Illinois and is quite common (see Distribution Map). Habitats include savannas, sandy savannas, black soil prairies, sand prairies, gravel prairies, dolomite prairies, thickets, fens, seeps, ditches, roadsides, areas along railroads (including the gravel ballast), old fields, and waste areas. This plant is often found in degraded areas and is rather weedy; however, it also occurs in higher quality habitats, especially where the soil is rather sandy or gravelly.

More info on this topic.

This species can be found in the following regions of the western United States (according to the Bureau of Land Management classification of Physiographic Regions of the western United States):

    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

Equisetum calderi B. Boivin:
Canada (North America)

Note: This information is based on publications available through Tropicos and may not represent the entire distribution. Tropicos does not categorize distributions as native or non-native.

Equisetum arvense var. boreale Ledeb.:
United States (North America)

Note: This information is based on publications available through Tropicos and may not represent the entire distribution. Tropicos does not categorize distributions as native or non-native.

Equisetum arvense L.:
Canada (North America)
Japan (Asia)
Russian Federation (Asia)
South Korea (Asia)
United States (North America)
China (Asia)
Bolivia (South America)

Note: This information is based on publications available through Tropicos and may not represent the entire distribution. Tropicos does not categorize distributions as native or non-native.

Greenland; St. Pierre and Miquelon; Alta., B.C., Man., N.B., Nfld., N.W.T., N.S., Ont., P.E.I., Que., Sask., Yukon; all states except Fla., La., Miss., S.C.; Eurasia s to Himalayas, c China, Korea, Japan.

Canada

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

More info for the term: rhizome

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].

Aerial stems dimorphic; vegetative stems green, branched, 2--60(--100) cm; hollow center 1/3--2/3 stem diam. Sheaths squarish in face view, 2--5(--10) × 2--5(--9) mm; teeth dark, 4--14, narrow, 1--3.5 mm, often cohering in pairs. Branches in regular whorls, ascending, solid; ridges 3--4; valleys channeled; 1st internode of each branch longer than subtending stem sheath; sheath teeth attenuate. Fertile stems brown, lacking stomates, unbranched, shorter than vegetative stems, with larger sheaths, fleshy, ephemeral. 2 n =ca. 216.

More info for the term: facultative wetland species

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)

More info for the terms: fern, selection, shrub

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]

More info on this topic.

This species is known to occur in association with the following cover types (as classified by the Society of American Foresters):

More info for the term: swamp

     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

More info on this topic.

This species is known to occur in association with the following plant community types (as classified by Küchler 1964):

More info for the term: shrub

   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

More info on this topic.

This species is known to occur in the following ecosystem types (as named by the U.S. Forest Service in their Forest and Range Ecosystem [FRES] Type classification):

   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

Common Horsetail is found in every county of Illinois and is quite common (see Distribution Map). Habitats include savannas, sandy savannas, black soil prairies, sand prairies, gravel prairies, dolomite prairies, thickets, fens, seeps, ditches, roadsides, areas along railroads (including the gravel ballast), old fields, and waste areas. This plant is often found in degraded areas and is rather weedy; however, it also occurs in higher quality habitats, especially where the soil is rather sandy or gravelly.

Cones maturing in early spring. Roadsides, riverbanks, fields, marshes, pastures, tundra; 0--3200m.

Where it occurs in dense colonies, Common Horsetail provides cover for small mammals and birds. The coarse stems are not often eaten by mammalian herbivores because of their silica deposits; these stems are also somewhat toxic because thiamin-deficiency can result if they are eaten by the same animals. Overall, the ecological value of this plant to wildlife is low.

In Great Britain and/or Ireland:
Foodplant / saprobe
seriate or widely scattered, covered pycnidium of Ascochyta coelomycetous anamorph of Ascochyta equiseti is saprobic on locally bleached, dead, dry stem of Equisetum arvense
Remarks: season: 2-4

Foodplant / internal feeder
larva of Grypus equiseti feeds within stem of Equisetum arvense

Foodplant / miner
larva of Hippuriphila modeeri mines live, blackened stem of Equisetum arvense
Remarks: season: summer
Other: sole host/prey

Foodplant / saprobe
apothecium of Hymenoscyphus rhodoleucus is saprobic on dead stem of Equisetum arvense
Remarks: season: 4-9

Foodplant / miner
larva of Liriomyza equiseti mines live, blackened branch (thick) of Equisetum arvense
Other: sole host/prey

Foodplant / miner
larva of Liriomyza occipitalis mines live, non-blackened branch (narrow) of Equisetum arvense
Other: sole host/prey

Foodplant / saprobe
scattered, immersed, globose, brown pycnidium of Stagonospora coelomycetous anamorph of Stagonospora equisetina is saprobic on dead stem of Equisetum arvense

Foodplant / saprobe
sometimes in rows acervulus of Titaeospora coelomycetous anamorph of Titaeospora equiseti is saprobic on dying, locally reddish-brown stained stem of Equisetum arvense
Remarks: season: 3-4

More info for the term: prescribed fire

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.

More info for the terms: climax, frequency, gametophyte, presence, wildfire

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].

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].

More info for the terms: geophyte, ground residual colonizer, rhizome

   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)

More info for the term: fuel

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].

More info on this topic.

More info for the terms: climax, cover, succession

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].

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.

More info on this topic.

More info for the term: geophyte

  
   Geophyte

More info for the terms: fern, fern ally

Fern or Fern Ally

More info on this topic.

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].

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 11
Specimens with Barcodes: 33
Species With Barcodes: 1

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 0
Specimens with Barcodes: 20
Species With Barcodes: 1

Rounded Global Status Rank: G5 - Secure

Canada

Rounded National Status Rank: N5 - Secure

United States

Rounded National Status Rank: N5 - Secure

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].

The preference is full or partial sun and moist to mesic conditions. Different kinds of soil are readily tolerated, including those containing sand, gravel, and fertile loam. This plant spreads readily by its rhizomes and can be very aggressive. It is possible to eliminate a vegetative colony by spreading a black plastic sheet across the entire area where it occurs. This sheet should remain in place for at least a year.