Index of Species Information

SPECIES:  Urtica dioica


SPECIES: Urtica dioica
AUTHORSHIP AND CITATION : Carey, Jennifer H. 1995. Urtica dioica. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: [].

ABBREVIATION : URTDIO SYNONYMS : Urtica gracilis Ait. [13,24,25] Urtica holosericea Nutt. [53] Urtica procera Muhl. [13,54] SCS PLANT CODE : URDI URDID URDIG URDIH COMMON NAMES : stinging nettle American stinging nettle European stinging nettle hoary nettle TAXONOMY : The currently accepted scientific name for stinging nettle is Urtica dioica L. (Urticaceae) [15,17,21,28,49]. Urtica dioica is a polymorphic complex in North America with a confusing taxonomic history; many varieties and subspecies have been described including an introduced subspecies from Europe. Although formerly separated into four species [13], most recent authors agree that the North American plants cannot be distinguished at the species level from each other and from European plants. The following three subspecies are currently recognized [3,17,21,28,51]: U. d. ssp. dioica (European stinging nettle) U. d. ssp. gracilis (Ait.) Selander (American stinging nettle) U. d. ssp. holosericea (Nutt.) Thorne (hoary nettle) LIFE FORM : Forb FEDERAL LEGAL STATUS : No special status OTHER STATUS : NO-ENTRY


SPECIES: Urtica dioica
GENERAL DISTRIBUTION : American stinging nettle is the most common subspecies in temperate North America and occurs throughout Canada and much of the United States.  In the East and Midwest, American stinging nettle occurs as far south as Virginia, Missouri, and Kansas; in the West, it occurs south along the coast to central California and south in the Rocky Mountains to Mexico.  European stinging nettle occurs primarily along the Atlantic Coast from Newfoundland south to Georgia and Alabama.  It is recently adventive westward in Missouri, Oklahoma, Oregon, and Alaska.  Hoary nettle is native to the western United States.  It occurs from eastern Washington south through California to Mexico, east to northern Arizona and extreme northwestern Colorado, and north to western Wyoming and southwestern Montana [51]. ECOSYSTEMS :    Stinging nettle probably occurs in most ecosystems. STATES :      AL  AK  AZ  AR  CA  CO  CT  DE  GA  ID      IL  IN  IA  KS  KY  LA  ME  MD  MA  MI      MN  MS  MO  MT  NE  NV  NH  NJ  NM  NY      NC  ND  OH  OK  OR  PA  RI  SC  SD  TN      TX  UT  VT  VA  WA  WV  WI  WY  DC  AB      BC  MB  NB  NF  NT  NS  ON  PE  PQ  SK      YT  MEXICO 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 :    K002  Cedar-hemlock-Douglas-fir forest    K005  Mixed conifer forest    K011  Western ponderosa forest    K012  Douglas-fir forest    K013  Cedar-hemlock-pine forest    K030  California oakwoods    K037  Mountain-mahogany-oak scrub    K093  Great Lakes spruce-fir forest    K095  Great Lakes pine forest    K096  Northeastern spruce-fir forest    K097  Southeastern spruce-fir forest    K098  Northern floodplain forest    K102  Beech-maple forest    K113  Southern floodplain forest SAF COVER TYPES :     63  Cottonwood    222  Black cottonwood-willow    228  Western redcedar    229  Pacific Douglas-fir    230  Douglas-fir-western hemlock    234  Douglas-fir-tanoak-Pacific madrone    237  Interior ponderosa pine    243  Sierra Nevada mixed conifer    244  Pacific ponderosa pine-Douglas-fir    245  Pacific ponderosa pine    246  California black oak    249  Canyon live oak    250  Blue oak-foothills pine    255  California coast live oak SRM (RANGELAND) COVER TYPES :    201  Blue oak woodland    202  Coast live oak woodland    203  Riparian woodland    217  Wetlands    409  Tall forb    413  Gambel oak    422  Riparian    805  Riparian HABITAT TYPES AND PLANT COMMUNITIES : Stinging nettle is a common understory component of riparian communities [30,50,52].  In the Santa Ana Mountains along the southern California Coast, American stinging nettle occurs in the understory of a riparian woodland dominated by California sycamore (Platanus racemosa), white alder (Alnus rhombifolia), and red willow (Salix laevigata) [48].  In Kern County, California, hoary nettle is abundant in the understory of a Fremont cottonwood (Populus fremontii), Pacific willow (Salix lasiandra), and red willow community [23].  In Montana, American stinging nettle occurs in a western redcedar (Thuja plicata) community in a ravine dissected by spring run-off channels [18]. Stinging nettle occurs in and adjacent to marshes and meadows.  In North Dakota, stinging nettle occurs in a sedge (Carex spp.)-dominated zone between an emergent marsh and upland meadow [29]. Stinging nettle occurs in moist forest communities in the southern Appalachian Mountains [4].


SPECIES: Urtica dioica
IMPORTANCE TO LIVESTOCK AND WILDLIFE : The wildlife food value of stinging nettle is listed as poor [10], probably because of stinging hairs on the foliage.  Stinging nettle provides cover for small animals [10,16,42]. PALATABILITY : Stinging nettle is unpalatable to livestock [10]. NUTRITIONAL VALUE : Stinging nettle is very nutritious.  Stinging nettle hay contains 21 to 23 percent crude protein, 3 to 5 percent crude fats, 35 to 39 percent non-nitrogen extracts, 9 to 21 percent crude fiber, and 19 to 29 percent ash.  Amino acids in dehydrated stinging nettle meal are nutritionally superior to those of dehydrated alfalfa (Medicago sativa) meal [1]. COVER VALUE : Mallards and gadwalls prefer tall, dense nesting cover provided by graminoids and herbaceous vegetation including stinging nettle [42]. Stinging nettle is a component of roughs which are good cover for sharp-tailed grouse in Wisconsin [16].  Although listed as generally poor wildlife cover by Dittberner and Olson [10], stinging nettle cover is listed as fair for small nongame birds and mammals in Utah. VALUE FOR REHABILITATION OF DISTURBED SITES : Stinging nettle may be tolerant of heavy metals.  It is an abundant species on metal-contaminated soil on the floodplain of a former Rhine River estuary in the Netherlands [31]. OTHER USES AND VALUES : Boiled stinging nettle leaves are edible and can be substituted for spinach [1,11]. Stinging nettle fibers were used by Native Americans in the Northwest to make twine, fishing nets, and rope.  Stinging nettle has many medicinal uses [45]. OTHER MANAGEMENT CONSIDERATIONS : Stinging nettle is considered a weedy, invasive species.  It is listed as a noxious weed in several Canadian provinces.  Stinging nettle hairs are irritating to human skin, and the pollen is a major contributor to summer hay fever [1]. When distributed through the soil by disturbance such as mechanical cultivation, stinging nettle rhizomes can establish dense new colonies. However, repeated plowing will eliminate stinging nettle.  When mowed, stinging nettle sends up numerous bushy shoots [1]. Spraying with 2,4-D herbicide substantially reduced stinging nettle cover in a central Wisconsin marsh [19]. Stinging nettle is used by foresters as an indicator of high soil fertility [38]. Insects, micro-organisms, and viruses associated with stinging nettle are listed [1].


SPECIES: Urtica dioica
GENERAL BOTANICAL CHARACTERISTICS : Stinging nettle is an erect, perennial, rhizomatous forb which forms dense clonal patches.  Stout stems grow 3.3 to 6.6 feet (1-2 m) tall. Leaves, stems, and flowers are sparsely to moderately covered with stinging hairs.  Two subspecies, American stinging nettle and hoary nettle, are native; the third subspecies in North America, European stinging nettle, was introduced in the mid-1800's.  American stinging nettle and hoary nettle are predominantly monoecious whereas European stinging nettle is typically dioecious.  The fruit is an achene [1,51]. Stinging nettle has both epigeal and shallow subterranean rhizomes [35]. RAUNKIAER LIFE FORM :       Hemicryptophyte REGENERATION PROCESSES : Stinging nettle reproduces vegetatively and by seed. Stinging nettle produces abundant seed.  Plants growing in the shade produce approximately 500 to 5,000 seeds per shoot and plants growing in full sunlight produce 10,000 to 20,000 seeds per shoot.  Seeds remain on the plant until frost when they fall to the ground.  Seeds are not dormant and can germinate 5 to 10 days after maturity [1].  Buried stinging nettle seeds persist an undetermined length of time in the seedbank [7,26,33,34,44].  Stinging nettle seedlings emerged from unflooded substrate samples collected from the Delta Marsh, Manitoba [33].  Stinging nettle seeds, mostly buried less than 2 inches (5 cm) deep, occurred in the seedbanks of three forest communities in Idaho [26].  Stinging nettle seedlings emerged from soil samples collected from a ponderosa pine (Pinus ponderosa)/common snowberry (Symphoricarpos albus) habitat type in Washington.  April collections contained 48 stinging nettle seeds per square foot (533/sq m) and October collections contained 6 seeds per square foot (67/sq m).  Most stinging nettle seeds were buried less than 4 inches (10 cm) deep, but some were present to 10 inches (25 cm) [34].  Stinging nettle seeds have germinated in the greenhouse after 10 years of storage [1]. Stinging nettle spreads and reproduces vegetatively by rhizomes. Seedlings initiate vegetative spread in the first growing season.  A rhizome planted in late summer can spread into an 8.2 foot (2.5 m) diameter area by the following year [1]. Stinging nettle has a strong shoot thrust.  The ability to generate mechanical force enables the plant to extend its shoots vertically into dominant aerial positions [6]. SITE CHARACTERISTICS : Stinging nettle occurs in moist sites along streams, coulees, and ditches, on mountain slopes, in woodland clearings, and in disturbed areas.  Stinging nettle generally grows on deep, rich soils [1,51]. American stinging nettle occurs from sea level to subalpine elevations. Hoary nettle occurs from sea level to 10,000 feet (3,000 m) elevation in the southern part of its range and from 2,300 to 6,600 feet (700-2,000 m) elevation in the northern part of its range [51].  Stinging nettle persists in northern climates, spreading vegetatively rather than by seed [40]. Stinging nettle occurs both in wetlands and in uplands.  It is a facultative wetland species [36].  Stinging nettle is present in the seasonally flooded emergent zone of oxbow lakes along the Connecticut River [22].  Persistent flooding kills stinging nettle [20]. SUCCESSIONAL STATUS : Stinging nettle is probably intermediate in shade tolerance.  It occurs and produces seed in shady habitats but produces more seed in full sun [1]. Stinging nettle establishes colonies from which other plants are virtually excluded.  Competition from grass may limit the spread of stinging nettle clones [1] Stinging nettle invades disturbed sites.  It invades forest plantations in Great Britain when bracken fern (Pteridium aquilinum) is artificially removed [5].  Stinging nettle colonizes wetland sites when water levels drop [20,33].  It is an increaser on periodically flooded areas along Idaho streams [37]. SEASONAL DEVELOPMENT : Stinging nettle sends new shoots up each year from perennating buds on rhizomes.  Maximum root development occurs in the spring prior to flowering.  American stinging nettle flowers from late May to October, European stinging nettle flowers from June to October, and hoary nettle flowers from July to October.  In northern areas, flowering is condensed into a shorter time period, ending in late August [1,51].


SPECIES: Urtica dioica
FIRE ECOLOGY OR ADAPTATIONS : Stinging nettle survives fire by sprouting from rhizomes.  Removal of litter by fire may encourage stinging nettle growth and provide suitable germination sites for seed.  However, frequent fire during the growing season may reduce stinging nettle [43]. POSTFIRE REGENERATION STRATEGY :    Rhizomatous herb, rhizome in soil    Ground residual colonizer (on-site, initial community)    Initial-offsite colonizer (off-site, initial community)


SPECIES: Urtica dioica
IMMEDIATE FIRE EFFECT ON PLANT : Stinging nettle is probably top-killed by fire.  Perennating buds on shallow rhizomes probably survive low-severity fire. DISCUSSION AND QUALIFICATION OF FIRE EFFECT : NO-ENTRY PLANT RESPONSE TO FIRE : Stinging nettle regenerates from buried rhizomes and/or seed after fire. Stinging nettle bloomed during the first postfire growing season on a ravine site in western Montana that burned in mid-July.  Although stinging nettle thrives on disturbance, its rate of spread after the fire on this site may have been slowed by competition from orchard grass (Dactylis glomerata) [8]. One year after a wildfire in northern Utah, stinging nettle was present at low frequency on plots in a burned Gambel oak (Quercus gambelii) brush community but was not present on adjacent unburned plots [30]. In southern California, large amounts of sediment were deposited in a riparian zone after a July fire in a riparian forest dominated by coast live oak (Q. agrifolia), white alder, and California sycamore.  Stinging nettle emerged from the sediment and was a common species on lower and middle terraces in the riparian zone during the 3 years following the fire [9]. Stinging nettle occurred in a central Wisconsin marsh dominated by goldenrod (Solidago spp.), butter-and-eggs (Linaria vulgaris), white meadowsweet (Spiraea alba), and grasses.  Fire was prescribed on two sites in the spring 1 week after snowmelt.  Approximately 96 percent of the dry surface fuels were eliminated.  Vegetation was inventoried during the growing seasons before and after the fires.  Stinging nettle prefire and postfire covers are as follows [19]: Prefire cover Postfire cover Site 1              2.0%      1.8% Site 2             <0.5%      2.5% Stinging nettle shoot density and biomass after fire depends on the season of burn.  Stinging nettle shoots per square meter and biomass measured the first growing season after each fire in a common reed (Phragmites australis) stand in Delta Marsh, Manitoba, are as follows:       Density                         Biomass               (nonseedling shoots/sq m)             (grams/sq m) Control          6.7 36.2 Summer fire 18.4 33.9 Fall fire  4.9 10.3 Spring fire 18.8 52.9 Stinging nettle biomass was less than in the control the first growing season after the fall fire.  The authors suggest that the stinging nettle rhizome buds may have succumbed to winterkill after the fall fire because there were no dead standing canes to trap snow and insulate the soil.  Stinging nettle biomass was greater than in the control in the first growing season after the spring fire.  Stinging nettle is capable of fast growth and, with the removal of common reed litter by fire, was able to compete with the common reed.  Stinging nettle biomass did not differ substantially from the control 1 year after the summer fire. There were more shoots per meter after the summer fire but the shoots were smaller than in the control, possibly because resources were depleted by regrowth immediately after the summer fire [43]. Stinging nettle seedlings established at a density of 6.9 seedlings per square foot (76.8/sq m) 1 month after the summer fire.  Only a few seedlings established after the fall and spring fires [43].  DISCUSSION AND QUALIFICATION OF PLANT RESPONSE : Hamilton's Research Papers (Hamilton 2006a, Hamilton 2006b)and Metlen and others' Research Project Summary provide information on prescribed fire and postfire response of many plant species including stinging nettle. FIRE MANAGEMENT CONSIDERATIONS : NO-ENTRY

References for species: Urtica dioica

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