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SPECIES: Galium aparine
Walter Knight © California Academy of Sciences
A distributional map of stickywilly is accessible through Plants database.ECOSYSTEMS :
Northwest: In the Northwest, stickywilly is described in coniferous and deciduous forests, shrublands, and grassland communities.
Coniferous forests: Stickywilly is typical in mixed conifer/blueberry/American skunkcabbage (Vaccinium spp./Lysichiton americanus) habitats of southeastern Alaska. Typical conifers in this vegetation type include western hemlock (Tsuga heterophylla), mountain hemlock (T. mertensiana), Alaska-cedar (Chamaecyparis nootkatensis), Sitka spruce (Picea sitchensis), and shore pine (Pinus contorta var. contorta) . On Saturna Island, British Columbia, stickywilly occurs in habitats dominated by Douglas-fir (Pseudotsuga menziesii), western hemlock, and salal (Gaultheria shallon) . In other parts of southern British Columbia, ponderosa pine is the climax species in communities where stickywilly occurs . Stickywilly is also found in ponderosa pine (P. ponderosa) communities of Washington, Oregon, Idaho, and western Montana [115,168]. In the Puget Trough of Washington, stickywilly occurs in Douglas-fir-Pacific madrone/pink honeysuckle (Arbutus menziesii/Lonicera hispidula) and Douglas-fir-Pacific madrone/salal vegetation associations . In central Idaho, researchers encountered stickywilly in Douglas-fir/ninebark (Physocarpus malvaceus) and grand fir/big huckleberry (Abies grandis/Vaccinium membranaceum) habitats .
Deciduous and mixed forests: Stickywilly is present at frequencies of 81%-100% in Oregon white oak (Quercus garryana)-dominated sites in coastal British Columbia where blue wildrye (Elymus glaucus) is also common . On the southern portion of Waldron Island, Washington, a white oak/stickywilly woodland community type occurs on the southeastern slopes of Pt. Disney . In southwestern Oregon, stickywilly occurs with at least 50% constancy in Oregon white oak-Douglas-fir/poison-oak (Toxicodendron diversilobum), Port-Orford-cedar (C. lawsoniana)-western hemlock/western sword fern (Polystichum munitum), and California red fir-white fir/deer oak/sidebells wintergreen (Abies magnifica shatensis-A. concolor/Q. sadleriana/Orthilia secunda) communities . Stickywilly is also found in Oregon white oak-true mountain-mahogany (Cercocarpus montanus) vegetation types in southwestern Oregon . In green ash (Fraxinus pennsylvanica) woodlands of eastern Montana, stickywilly occurs at 11% frequency .
Shrub- and grassland communities: Stickywilly occurs in southeastern Oregon's common snowberry-rose (Symphoricarpos albus-Rosa spp.)  and in northern Idaho's bluebunch wheatgrass/Sandberg bluegrass (Pseudoroegneria spicata-Poa secunda) vegetation associations .
Southwest: A variety of southwestern environments and habitats is occupied by stickywilly.
Coniferous forests: Stickywilly is common in several redwood (Sequoia sempervirens)-dominated vegetation types on northern California's coasts. On intermediate elevation sites where the dominant understory species is dwarf Oregon-grape (Berberis nervosa), stickywilly occurrence is greatest. On low- and high-elevation sites where deer fern (Blechnum spicant) and Pacific madrone codominate, respectively, stickywilly is still present . Stickywilly is described in spruce-fir (Picea spp.-Abies spp.) communities in Utah . In northeastern Arizona, stickywilly occupies Tsegi Canyon's Douglas-fir dominated forests . Along southern Arizona's San Pedro River, stickywilly occupies riparian sites with saltcedar (Tamarix spp.), mule's fat (Baccharis salicifolia), and singlewhorl burrobrush (Hymenoclea monogyra) . Stickywilly is also found in pinyon-juniper (Pinus spp.-Juniperus spp.) communities of the Great Basin Desert [71,161].
Deciduous and mixed forests: In the oak (Quercus spp.) woodlands of California's North Coast Range, stickywilly occupies several communities identified by the presence of snowberry, orchardgrass (Dactylis glomerata), Columbian larkspur (Delphinium trolliifolium), Lewis' mockorange (Philadelphus lewisii), bladder-fern (Cystopteris spp.), Sierra gooseberry (Ribes roezlii), varileaf phacelia (Phacelia heterophylla), and dogstail grass (Cynosurus spp.) . Stickywilly in the Berkeley Hills, occurs in oak woodlands dominated by coast live oak (Q. agrifolia), bigleaf maple (Acer macrophyllum), California bay (Umbellularia californica), and poison-oak . In riparian areas of California's Central Valley, stickywilly is found among cottonwoods (Populus spp.), willows (Salix spp.), boxelder (A. negundo), California black walnut (Juglans californica), Douglas' sagewort (Artemisia douglasiana), and California manroot (Marah fabaceus) .
In the Sierra Nevada foothills, stickywilly occurs in chaparral communities where blue oak (Q. douglasii), gray pine (Pinus sabiniana), interior live oak (Q. wislizenii), and wedgeleaf ceanothus (Ceanothus cuneatus) are typical . In southern California's scrub oak (Q. berberidifolia) communities, stickywilly occurs with Eastwood manzanita (Arctostaphylos glandulosa) and chamise .
In Gambel oak (Q. gambelii)-dominated sites of central and northern Utah, stickywilly is common. Other associated species include chokecherry (Prunus virginiana), bigtooth maple (A. grandidentatum), mountain snowberry (S. oreophilus), Saskatoon serviceberry (Amelanchier alnifolia), cheatgrass (Bromus tectorum), Kentucky bluegrass (Poa pratensis), and bluebunch wheatgrass [80,114]. Stickywilly occurs in quaking aspen (Populus tremuloides)-dominated sites of Utah, too [68,161].
Shrub- and grassland communities: Stickywilly's presence in big sagebrush (Artemisia tridentata) communities is noted by several authors [71,114,161]. In Utah's Wasatch Mountains State Park, antelope bitterbrush (Purshia tridentata) and bluebunch wheatgrass are common sagebrush associates . In California's chaparral communities stickywilly is common. On Santa Cruz Island, stickywilly occurs in scrub oak chaparral, chamise (Adenostoma fasciculatum) chaparral, and hollyleaf cherry (Prunus ilicifolia) woodlands . Stickywilly is described in grass-forb habitat types in northern Utah with brome grasses (Bromus spp.), prairie Junegrass (Koeleria macrantha), and lupines (Lupinus spp.) .
North-central: Hardwood forests and prairies of the north-central U.S. are typical stickywilly habitat.
Deciduous forests: In the bur oak/eastern hophornbeam (Q. macrocarpa/Ostrya virginiana) habitat type of the Great Plains Province, stickywilly has 75% constancy . In southern Wisconsin, stickywilly occurs with sugar maple (Acer saccharum), slippery elm (Ulmus rubra), American elm (U. americana), and basswood (Tilia americana) . Stickywilly is typical of forests adjacent to river systems or wet meadows where sugar maple, American hornbeam (Carpinus caroliniana), northern spicebush (Lindera benzoin), eastern hophornbeam, yellow-poplar (Liriodendron tulipifera), northern red oak (Q. rubra), white oak (Q. alba), bur oak, shagbark hickory (Carya ovata), shellbark hickory (C. laciniosa), ash (Fraxinus spp.), eastern redcedar (Juniperus virginiana), elm (Ulmus spp.) and/or basswood may characterize the overstory vegetation [73,76,77,146]. Associated forbs and shrubs may include false lily-of-the-valley (Maianthemum racemosum ssp. racemosum), snow trillium (Trillium grandiflorum), sweet cicely (Osmorhiza claytonii), poison-ivy (Toxicodendron radicans), trumpet creeper (Campsis radicans), Canadian woodnettle (Laportea canadensis), and bristly buttercup (Ranunculus hispidus var. nitidus) [76,146] On floodplains where stickywilly also occurs, boxelder, cottonwood, willow, hackberry (Celtis spp.) and walnut (Juglans spp.) are typical .
Grassland communities: In Jasper County, Illinois, stickywilly occurs in a tallgrass prairie dominated by big bluestem (Andropogon gerardii), little bluestem (Schizachyrium scoparium), and showy partridgepea (Cassia fasciculata) . Stickywilly is considered a "characteristic forb" in a moist switchgrass (Panicum virgatum) community type with big bluestem, bluegrasses (Poa spp.), and Scribner's rosette grass (Dichanthelium oligosanthes var. scribnerianum) .
In the south-central
U.S., stickywilly is commonly described in hardwood bottomland forests.
Along the Trinity River of Texas, stickywilly occurs with an overstory of winged elm (U. alata), post oak (Q. stellata), and Mexican plum (Prunus mexicana). The understory is Virginia creeper (Parthenocissus quinquefolia) and saw greenbrier (Smilax bona-nox) . On the Mississippi floodplain in southern Louisiana, stickywilly is found in bottomland hardwood-baldcypress (Taxodium distichum) forests. The dominant overstory species are sugarberry (Celtis laevigata), green ash, and sweetgum (Liquidambar styraciflua) .
Northeast: Stickywilly is described in northeastern hardwood forests, meadows, and abandoned fields.
Mixed forests: Riparian areas and floodplains typically contain stickywilly. In north-central Ohio, stickywilly occurs in old-growth mixed oak-hickory (Carya spp.) floodplain forests and in upland riparian forests dominated by beech (Fagus spp.) and maple (Acer spp.) . In the Lake Agassiz Peatlands of north-central Minnesota stickywilly occurs in rich swamp forests. Northern white-cedar (Thuja occidentalis), black ash (Fraxinus nigra), tamarack (Larix laricina), and white spruce (Picea glauca) are characteristic species in swamp forests where stickywilly is present with low coverages . Stickywilly was a major understory species in oak-sugar maple forests of southwestern Ohio where both white and northern red oak occur. Stickywilly frequency was lowest in the youngest stands (40-year-old), where water content and light levels were lowest . On the floodplains of the Potomac River (Maryland side) stickywilly occurs with an overstory of boxelder, pawpaw (Asimina triloba), hackberry (Celtis occidentalis), northern spicebush, and sycamore (Platanus occidentalis) .
Meadow communities: Stickywilly is described in wet meadows of Quebec's Huntingdon Marsh near the Ontario and New York borders. Also typical are bluejoint reedgrass (Calamagrostis canadensis), sedges (Carex spp.), and common marsh bedstraw (Galium palustre) .
Old fields and urban communities: In the abandoned fields of central and western New York, stickywilly is present with several shrubs including Morrow's honeysuckle (Lonicera morrowii), gray dogwood (Cornus racemosa), red-osier dogwood (C. sericea), and silky dogwood (C. amomum). Common forbs and grasses include Canada goldenrod (Solidago canadensis), timothy (Phleum pratense), quackgrass (Elymus repens), and Canada bluegrass (Poa compressa) . In the Wave Hill natural area in Bronx, New York, stickywilly persists in open woodland interspaces with a variety of nonnative vegetation including Amur peppervine (Ampelopsis brevipedunculata), Amur honeysuckle (L. maackii), garlic mustard (Alliaria petiolata), and Japanese knotweed (Polygonum cuspidatum) .
Southeast: Stickywilly is typical of southeastern riparian and floodplain forests.Deciduous forests: In northern Kentucky mixed mesophytic forests, sugar maple, white ash (Fraxinus americana), sycamore, boxelder, and northern spicebush provide the canopy for stickywilly . Sweetgum, yellow-poplar, ash, elm, and northern red maple commonly occur with stickywilly in bottomland mixed hardwood forests in the Piedmont of North Carolina .
© 2005 Keir Morse
© 2004 Carol W. Witham
GENERAL BOTANICAL CHARACTERISTICS:
This description provides characteristics that may be relevant to fire ecology, and is not meant for identification. Keys for identification are available [11,25,41,57,58,65,71,94,129,158,161,165,167].
Stickywilly is an annual forb [25,44,58,143] that due to its highly plastic nature can grow as a winter or summer annual in temperate regions . Under certain environmental conditions, stickywilly may grow more like a biennial . The stickywilly root system is a shallow, branching taproot. Stickywilly has weak square stems with few branches [25,41,44,58]. Weak stems give stickywilly a gangly appearance, and tangles of stickywilly's scrambling stems with nearby vegetation are inevitable [44,143]. This growth form allows stickywilly a spread of up to 6 feet (1.8 m) . At the stem angles are hooked hairs or bristles that further aid in clambering and provide for plant dispersal [21,41,44].
A distinct characteristic of bedstraw species (Galium spp.) is leaves arranged in whorls. Stickywilly typically displays simple linear leaves (0.4 to 3.2 inches long (1-8 cm)) in whorls of 8. However, whorls of 6 and 7 leaves occur as well [25,41,44,58,62,143]. Flowers are perfect cymes and fruits are schizocarps that measure between 1-4 mm in diameter, but 3-4 mm is more typical [44,57,143]. Seeds are covered with sticky hooked hairs [21,25,58]. When found on dry sites, stickywilly leaves measure 0.4 to 1.6 inches (1-4 cm) long, and fruits typically range from 1.5 to 3 mm in diameter .
Look-alike species: Stickywilly can be mistaken with Marin County bedstraw (Galium spurium) especially when found in crops or disturbed sites. Marin County bedstraw is a more aggressive, nonnative species tolerant of dry sunny areas. The 2 species are unreliably distinguished by habitat, but chromosome numbers distinguish them .RAUNKIAER  LIFE FORM:
Breeding system: Stickywilly produces perfect flowers [53,62] and is largely self-pollinating [28,62,103].
Pollination: In a review article, DeFelice  indicates that insects may pollinate stickywilly, and others  infrequently observed small bees and flower flies visiting stickywilly flowers.
Seed production: The information regarding seed production by stickywilly varies widely. A single stickywilly plant in North Dakota of average size, growing with little "competition" from other vegetation, produced 105 seeds . Royer and Dickinson  suggest that 1 plant can yield 400 seeds. Likewise in a review, DeFelice  reports 300 to 400 seeds produced per plant. In old fields of Tennessee, researchers compared the stickywilly seed rain in sassafras (Sassafras albidum) stands in different successional stages. In 5-15 year-old-stands, an estimated 22,000 stickywilly seeds/ha were collected on the ground. In stands over 50 years old, 81,000 seeds/ha were trapped on the ground, and 1,160,000 seeds were recovered from airborne collectors. No data were provided on stickywilly coverage in the study sites or distances from the trapping area .
Seed dispersal: Stickywilly is highly adapted for long-distance dispersal. The hooked bristles coating stickywilly seed easily attach to feathers, fur, and clothing [28,62,143,158]. The backward-turned bristles on leaves and stems also grip easily to animals, equipment, and clothing aiding in long-distance dispersal of this species . DeFelice  reports in a review that stickywilly seeds are light enough for wind dispersal and can float due to empty space between the 2 carpels.
In northern Delaware and southern Pennsylvania, researchers calculated migration rates for stickywilly based on plant distances from an old-growth ecotone to the furthest plant or to the furthest occurrence where plants grew at 1/2 peak density. Stickywilly's migration rates were 2.48 ± 0.71 m/year and 1.94 ± 0.30 m/year based on the furthest 1/2 peak density and furthest individual calculations, respectively. These high dispersal rates are likely the result of animal transport .
Seed banking: Estimates regarding amounts of seed banked and duration of seed viability in the soil for stickywilly are broad ranging. Royer and Dickinson  suggest stickywilly seed can retain viability for 6 years. After reviewing literature on this subject, DeFelice  indicates that seeds are viable in the soil for just 2 to 3 years.
In Pennsylvania, the existing vegetation and soil seed bank were compared in forested, prairie, and prairie edge sites. Stickywilly was present in 1 of the forested plots dominated by black walnut (Juglans nigra), black cherry (Prunus serotina), eastern white pine (Pinus strobus), and hawthorn (Crataegus spp.), but no stickywilly seed germinated in soil collected from any of the 3 sites . In Douglas-fir and grand fir forests of central Idaho where stickywilly occurred with 0%-6% constancy, researchers recovered only 2 viable seeds from 20 soil samples collected from early May to late August . Soil samples taken from ponderosa pine/common snowberry habitat types in southeastern Washington produced high stickywilly seed density estimates. In the area, stickywilly occupied 1% coverage and was 83% constant. From soil cores samples germinated at optimal conditions, researchers estimated 83 ± 169 seeds/m² and 417±225 seeds/m² in spring and fall soils, respectively. Seed densities were greatest in the litter layer .
Germination: Seed germination percentages are reduced by increased depth of burial and increased temperatures. Stickywilly seed requires burial to germinate. Germination in a laboratory setting was between 0% and 5% when seed was uncovered, but when buried at depths of between 2 and 10 mm, 60%-80% of seed germinated . When buried 3.9 inches (10 cm) below the soil surface, 5%-15% of seed germinated, and no seedlings emerged at 4.7 inches (12 cm) . Royer and Dickinson  claim that no seedlings emerge when seed is buried greater than 1.6 inches (4 cm) deep. In a review, Holm and others  suggest that seed will not germinate from depths of 1.6 inches (4 cm) when in heavy, firm soils, and when buried 3.9 inches (10 cm) deep in light soils, germination, flowering, and fruiting are delayed.
In the laboratory, Pratt and others  found that heat treatments significantly (p<0.05) reduced germination of stickywilly. Of 196 fall collected seeds, just 21 seeds germinated after being heated at 167 °F (75 °C) for 20 minutes then stratified at 32 °F (0 °C) for 60 days. No seeds survived a heat treatment of 212 °F (100 °C) for 20 minutes followed by cold stratification. The researchers concluded that fire likely kills stickywilly seed in the litter layer . Royer and Dickinson  report decreased germination when soil temperatures are above 68°F (20 °C).
Holm and others  report recovering viable seed from cattle, horse, pig, goat, and bird feces, while other reviewers, Malik and Vanden Born , describe increased germination percentages following animal digestion.
Seedling establishment/growth: Stickywilly develops rapidly. Root lengths may be 2 to 2.4 inches (5-6 cm) long by the time 1st leaves appear, and flowers can appear 8 weeks after germination . Seedlings may also appear throughout the growing season .
Studies in southwestern Ohio reveal that 79%-94% of seedlings survived to reproductive age planted on mixed northern red oak, hickory, sugar maple, and ash forests where the density of Amur honeysuckle ranged from 0.3-0.7 shrub/m² .
In a greenhouse, researchers compared the growth of stickywilly seed collected from Ontario, Illinois, Oklahoma, and California. Growth rate differences were apparent 6 weeks after planting done in August. Developmental differences in seeds of different localities are shown below :
|Seed source||Oklahoma||Ontario and California||IL|
|Height by late December||3.28 ft (1 m)||intermediate between Oklahoma and Illinois||6-7.9 inches (150-200 mm)|
|Flowering date||late December||early March||late January|
Asexual regeneration: Malik and Vanden Born  indicate that stickywilly does not reproduce vegetatively.SITE CHARACTERISTICS:
Climate: The ability to behave as a winter or summer annual  allows stickywilly a broad range of climatic tolerances. The climate patterns for several regions in which stickywilly occurs are provided below:
|Region||Summer max. and winter min. temp.||Annual precipitation||Other|
|Eastern Montana ||88-0.4 °F||11.4-16.1 inches||semiarid, continental climate|
|Wasatch Mts., northern Utah ||61-27 °F||15.4 inches||70-80 consecutive frost-free days|
|Northeastern Arizona ||100-55 °F||6.8-18.8 inches||semiarid to arid continental climate|
|Northern California ||100-19 °F||70.1-80 inches||Mediterranean climate, receives 90% of precipitation from Oct.-May|
|New York, Ontario and Quebec borders ||90 to -44 °F||39.8 inches,
includes 90.2 inches snowfall
|rainfall delivery consistent|
|North-central Ohio ( and references therein).||69-27 °F|| 35.4 inches,
snowfall 36 inches
|humid continental climate, 60% of precipitation falls from April-Sept.|
Elevation: Several western states reported elevational ranges for stickywilly:
|Arizona||Grand Canyon||1,201 to 7,999 feet (366-2,438 m) |
|California||southern||up to 7,500 feet (2,286 m) |
|Colorado||western||5,000 to 9,500 feet (1,524-2,896 m) |
|Montana||west-central||below 6,004 feet (1,830 m) |
|Nevada||5,400 to 7,500 feet (1,646-2,286 m) |
|New Mexico||5,000 to 9,000 feet (1,524-2,742 m) |
|Utah||3,002 to 10,007 feet (915-3,050 m) |
Soils: Stickywilly favors moist soils and tolerates sites with moderate to poor drainage . Rich loam, heavy organic soils with above average nitrogen and phosphorus content, and pH values between 5.5 and 8.0 are reportedly preferred in reviews [28,56,90].
In a Minnesota swamp forest where northern white-cedar, black ash, tamarack, and white spruce are common, stickywilly occurrence was indicative of minerotrophic conditions, a pH range between 5.8 and 7, and calcium contents of 10 to 25 ppm . In bottomlands of New York's north shore of Long Island, researchers compared the soil and vegetation composition in 1922 and 1985. In 1922, soil pH ranged from 6 to 7 and stickywilly was present, yet sites revisited and surveyed in 1985 had a pH of 4.1 and were without stickywilly. Researchers considered increased soil acidity the reason that stickywilly was unable to occupy the site .SUCCESSIONAL STATUS:
Shade relationships: Habitats providing light shade are preferred by stickywilly; however, deep shade and/or full sun conditions are tolerated in some environments. In greenhouse simulations, stickywilly root and shoot growth were significantly lower (p<0.001) under deep shade conditions. Height increases were greater under patchy light conditions than under deep shade . In central California, stickywilly produced more biomass when growing under live or dead blue oaks than when growing in open grasslands. The density of stickywilly was 1.3 g/m² under live trees, 2.0 g/m² growing under dead trees, and 0.2 g/m² in open grassland .
Comparisons between Douglas-fir forests of western Washington and Oregon revealed that stickywilly coverage and frequency were 0.2% and 20.8%, respectively, in forests characterized by well-spaced Douglas-fir trees between 21.6 and 25.6 inches (55-65 cm) dbh. Stickywilly was absent from forests with closely-spaced Douglas-fir trees between 11.8 and 17.7 inches (30-45 cm) dbh. .
Pyle  made comparisons between Maryland's Potomac River floodplain forests with different levels of shading and human use. The canopy of these floodplain forests were dominated by box elder and pawpaw. Stickywilly was present only on sites receiving the heaviest recreation use and the highest degree of shading. Stickywilly did not occur on sites with little to no human disturbance that received mid-levels of sunlight. The combined land use and shading variables make determining the most important factor affecting stickywilly presence impossible .
Recent disturbances/early succession: The following studies suggest that stickywilly is not necessarily encouraged through disturbances and that disturbance responses are likely situation dependent. Stickywilly was not present in 1-, 2-, or 3-year-old abandoned fields of Piedmont, North Carolina, but did occur in bottomland mixed-hardwood forests in the same area . In western Massachusetts, stickywilly occurred on marshes above the active flood plain but did not occur on annually flooded sites . In north-central Idaho, stickywilly was absent from the earliest seral communities within a western redcedar-western hemlock vegetation association . Following the excavation of hardwood bottomland forests near Dallas, Texas, Nixon  monitored early successional changes. Stickywilly was absent from the youngest sites (3 and 5 years since excavation) and had an importance value of 1 on sites excavated 47 years prior. The 3-, 5-, and 47-year-old forests were dominated by eastern cottonwood (Populus deltoides), black willow (Salix nigra), and sugarberry, respectively. On unexcavated forest sites, stickywilly had an importance value of 20 . On a debris flow along a second order stream in the Central Coast Range of Oregon, stickywilly presence was first recorded 7 years following the initiation of succession. Stickywilly was absent from sites visited 10 years following the debris flow .
In an Oregon white oak meadow of southwestern British Columbia, MacDougall  intentionally disturbed sites in an attempt to decrease nonnative species. Disturbances included burning, mowing, and removal of nonnative species. Some sites were treated in the fall, others in the summer and fall. All treated sites were grouped and considered disturbed, so differences between burning, mowing, or removal treatments were lost. On shallow soil sites (2 to 5.9 inches (5-15 cm)), the predisturbance coverage of stickywilly was 9.8% and postdisturbance coverage was 22.6%. On deep soil sites (>39.4 inches (100 cm)), the predisturbance and postdisturbance coverages of stickywilly were 2.5% and 2.3%, respectively .
Following a 1975 clearcut and slash burn in north-central California, McDonald  monitored early succession in a ponderosa pine community. Stickywilly was absent in the 1st, 3rd, and 4th posttreatment years and frequency was low in the 2nd and 5th posttreatment years. The percent frequency, density, and height (average of 3 tallest stems) of stickywilly are given below for all posttreatment monitoring years. Sites were exceptionally dry in 1976 and 1977 and were extremely wet in 1978 .
|Year||Frequency (%)||Density (plants/milacre)||Height (ft)|
Past disturbances/later succession: Stickywilly occupies developing, mature, and old-growth woodlands and forests but is generally more frequent in mid-successional stages. In Douglas-fir forests of Oregon's Cascade Range, stickywilly's frequency of occurrence was significantly greater (p<0.1) in mature (80-195 year-old-forests) than in old-growth (≥195 years) or young (<80 years) forests . In coast live oak woodlands of Berkeley Hills, California, stickywilly frequency was 5% to 52%, while frequency was 1% to 9% in San Francisco Bay woodlands considered successionally older . In a southeastern Washington ponderosa pine/common snowberry community representative of a middle stage of succession, stickywilly had 83% constancy and 1% cover .
Luken and Fonda  investigated changes in vegetation, canopy cover, and soil nitrogen as red alder (Alnus rubra) stands aged along the Hoh River in Washington. Soil nitrogen content increased and canopies became more open with age. Stickywilly frequency and cover were greatest in the 24-year-old red alder stands. The differences in stickywilly coverage and frequency in 14-, 24-, and 65-year-old red alder stands are presented below :
|Stand Age (years)||14||24||65|
In mature American beech-sugar maple forests of southwestern Ohio, canopy gaps were created by falling single American beech trees. Vegetation changes in different aged gaps (1-15 years) were monitored. The middle-aged gaps had significantly (p=0.05) greater coverage of stickywilly. The results are provided below; values followed by the same letter are not significantly different .
|Gap age (years)||1-2||5-7||12 & 15||Intact canopy|
|Stickywilly coverage (average)||0.4a||0.5b||0.4a||0.4a|
|California (southern)||March-July |
|Canada||late May-mid-June |
|Great Plains||May-August |
|Gulf and Atlantic coasts||April-July |
|Illinois (Jasper County)||1st flowers: mid-May|
|peak flowering: late May|
|last flowers_ mid-June |
|Illinois (southeast)||mid-April-mid June |
|New Mexico||June-September |
|North and South Carolina||July-August |
|North Dakota||flowering begins as early as May 21 or as late as June 13 |
|Texas (lower Rio Grande Valley)||May-June |
|Texas (north-central)||March-April |
|Utah (Wasatch Mts.)||mid-May-late June |
|Virginia (Blue Ridge Mts.)||April-May |
|West Virginia||April-June |
Fire regimes: Many diverse communities provide stickywilly habitat. The fire regimes are dictated by the overstory community. Stickywilly experiences extreme ranges in fire frequencies. Vegetation in Quebec's Huntingdon Marsh that includes stickywilly burns almost every fall or early spring. Researchers found evidence of previous growing season fires in 28% to 50% of the quadrats sampled, and 14% to 25% of quadrats burned in the last 2 or 3 years . Western Montana's rough fescue (Festuca altaica)-dominated grasslands that are also stickywilly habitat tolerate fire frequencies of between 5 and 10 years. Researchers based estimated fire frequencies on this community's postfire vegetation recovery . In the East, stickywilly is common in sugar maple communities where fires are exceptionally rare, occurring at greater than 1,000-year intervals . This range of fire regimes tolerated by stickywilly suggests that this species is fire tolerant but not fire dependent.
The following table provides fire return intervals for plant communities and ecosystems where stickywilly is important. This list may not be inclusive for all plant communities in which stickywilly occurs. Find further fire regime information for the plant communities in which this species may occur by entering the species name in the FEIS home page under "Find Fire Regimes".
|Community or Ecosystem||Dominant Species||Fire Return Interval Range (years)|
|silver fir-Douglas-fir||Abies amabilis-Pseudotsuga menziesii var. menziesii||> 200|
|grand fir||Abies grandis||35-200 |
|maple-beech-birch||Acer-Fagus-Betula spp.||> 1,000|
|silver maple-American elm||Acer saccharinum-Ulmus americana||< 35 to 200|
|sugar maple||Acer saccharum||> 1,000|
|sugar maple-basswood||Acer saccharum-Tilia americana||> 1,000 |
|California chaparral||Adenostoma and/or Arctostaphylos spp.||< 35 to < 100 |
|bluestem prairie||Andropogon gerardii var. gerardii-Schizachyrium scoparium||< 10 [78,111]|
|Nebraska sandhills prairie||Andropogon gerardii var. paucipilus-Schizachyrium scoparium||< 10|
|bluestem-Sacahuista prairie||Andropogon littoralis-Spartina spartinae||< 10 |
|silver sagebrush steppe||Artemisia cana||5-45 [55,117,169]|
|sagebrush steppe||Artemisia tridentata/Pseudoroegneria spicata||20-70 |
|basin big sagebrush||Artemisia tridentata var. tridentata||12-43 |
|mountain big sagebrush||Artemisia tridentata var. vaseyana||15-40 [6,20,100]|
|Wyoming big sagebrush||Artemisia tridentata var. wyomingensis||10-70 (40**) [156,172]|
|coastal sagebrush||Artemisia californica||< 35 to < 100 |
|plains grasslands||Bouteloua spp.||< 35 [111,169]|
|cheatgrass||Bromus tectorum||< 10 [112,162]|
|California montane chaparral||Ceanothus and/or Arctostaphylos spp.||50-100 |
|sugarberry-America elm-green ash||Celtis laevigata-Ulmus americana-Fraxinus pennsylvanica||< 35 to 200 |
|mountain-mahogany-Gambel oak scrub||Cercocarpus ledifolius-Quercus gambelii||< 35 to < 100 |
|beech-sugar maple||Fagus spp.-Acer saccharum||> 1,000|
|black ash||Fraxinus nigra||< 35 to 200 |
|juniper-oak savanna||Juniperus ashei-Quercus virginiana||< 35|
|Ashe juniper||Juniperus ashei||< 35|
|western juniper||Juniperus occidentalis||20-70|
|Rocky Mountain juniper||Juniperus scopulorum||< 35 |
|cedar glades||Juniperus virginiana||3-22 [50,111]|
|tamarack||Larix laricina||35-200 |
|western larch||Larix occidentalis||25-350 [5,13,27]|
|yellow-poplar||Liriodendron tulipifera||< 35 |
|Great Lakes spruce-fir||Picea-Abies spp.||35 to > 200|
|northeastern spruce-fir||Picea-Abies spp.||35-200 |
|southeastern spruce-fir||Picea-Abies spp.||35 to > 200 |
|Engelmann spruce-subalpine fir||Picea engelmannii-Abies lasiocarpa||35 to > 200 |
|black spruce||Picea mariana||35-200|
|conifer bog*||Picea mariana-Larix laricina||35-200 |
|pinyon-juniper||Pinus-Juniperus spp.||< 35 |
|Rocky Mountain lodgepole pine*||Pinus contorta var. latifolia||25-340 [12,13,147]|
|Sierra lodgepole pine*||Pinus contorta var. murrayana||35-200 |
|shortleaf pine||Pinus echinata||2-15|
|slash pine-hardwood||Pinus elliottii-variable||< 35|
|longleaf pine-scrub oak||Pinus palustris-Quercus spp.||6-10 |
|Pacific ponderosa pine*||Pinus ponderosa var. ponderosa||1-47 |
|interior ponderosa pine*||Pinus ponderosa var. scopulorum||2-30 [4,10,83]|
|Arizona pine||Pinus ponderosa var. arizonica||2-15 [10,24,128]|
|eastern white pine||Pinus strobus||35-200|
|eastern white pine-eastern hemlock||Pinus strobus-Tsuga canadensis||35-200|
|eastern white pine-northern red oak-red maple||Pinus strobus-Quercus rubra-Acer rubrum||35-200|
|Virginia pine||Pinus virginiana||10 to < 35|
|Virginia pine-oak||Pinus virginiana-Quercus spp.||10 to < 35|
|sycamore-sweetgum-American elm||Platanus occidentalis-Liquidambar styraciflua-Ulmus americana||< 35 to 200 |
|eastern cottonwood||Populus deltoides||< 35 to 200 |
|aspen-birch||Populus tremuloides-Betula papyrifera||35-200 [31,159]|
|quaking aspen (west of the Great Plains)||Populus tremuloides||7-120 [4,47,99]|
|black cherry-sugar maple||Prunus serotina-Acer saccharum||> 1,000 |
|mountain grasslands||Pseudoroegneria spicata||3-40 (10**) [3,4]|
|Rocky Mountain Douglas-fir*||Pseudotsuga menziesii var. glauca||25-100 [4,6,7]|
|coastal Douglas-fir*||Pseudotsuga menziesii var. menziesii||40-240 [4,104,121]|
|California mixed evergreen||Pseudotsuga menziesii var. menziesii-Lithocarpus densiflorus-Arbutus menziesii||< 35|
|California oakwoods||Quercus spp.||< 35 |
|oak-hickory||Quercus-Carya spp.||< 35 |
|oak-juniper woodland (Southwest)||Quercus-Juniperus spp.||< 35 to < 200 |
|northeastern oak-pine||Quercus-Pinus spp.||10 to < 35 |
|oak-gum-cypress||Quercus-Nyssa-spp.-Taxodium distichum||35 to > 200 |
|southeastern oak-pine||Quercus-Pinus spp.||< 10 |
|coast live oak||Quercus agrifolia||2-75 |
|white oak-black oak-northern red oak||Quercus alba-Q. velutina-Q. rubra||< 35 |
|canyon live oak||Quercus chrysolepis||<35 to 200|
|blue oak-foothills pine||Quercus douglasii-P. sabiniana||<35 |
|northern pin oak||Quercus ellipsoidalis||< 35 |
|Oregon white oak||Quercus garryana||< 35 |
|bear oak||Quercus ilicifolia||< 35 |
|California black oak||Quercus kelloggii||5-30 |
|bur oak||Quercus macrocarpa||< 10 |
|oak savanna||Quercus macrocarpa/Andropogon gerardii-Schizachyrium scoparium||2-14 [111,159]|
|chestnut oak||Quercus prinus||3-8|
|northern red oak||Quercus rubra||10 to < 35|
|post oak-blackjack oak||Quercus stellata-Q. marilandica||< 10|
|black oak||Quercus velutina||< 35|
|live oak||Quercus virginiana||10 to< 100 |
|interior live oak||Quercus wislizenii||< 35 |
|blackland prairie||Schizachyrium scoparium-Nassella leucotricha||< 10|
|Fayette prairie||Schizachyrium scoparium-Buchloe dactyloides||< 10 |
|little bluestem-grama prairie||Schizachyrium scoparium-Bouteloua spp.||< 35 |
|redwood||Sequoia sempervirens||5-200 [4,37,142]|
|baldcypress||Taxodium distichum var. distichum||100 to > 300|
|pondcypress||Taxodium distichum var. nutans||< 35 |
|western redcedar-western hemlock||Thuja plicata-Tsuga heterophylla||> 200 |
|eastern hemlock-yellow birch||Tsuga canadensis-Betula alleghaniensis||> 200 |
|western hemlock-Sitka spruce||Tsuga heterophylla-Picea sitchensis||> 200|
|mountain hemlock*||Tsuga mertensiana||35 to > 200 |
|elm-ash-cottonwood||Ulmus-Fraxinus-Populus spp.||< 35 to 200 [31,159]|
Coniferous forests: The following studies indicate that stickywilly is often absent from the 1st postfire year conifer communities. Several fires burned in 2 northeastern Oregon forests (Douglas-fir and subalpine fir) where stickywilly occurs. Moderately severe fires partially consumed the litter and woody debris, blackened shrub stems, and charred and partially burned tree trunks. Severe fires deeply charred tree trunks, consumed most branches, consumed litter and duff, and left a white ash layer. Stickywilly coverage in the 5th postfire year surpassed prefire coverages in moderate and severe burns. Pre- and postfire percent coverages for stickywilly are provided below :
|Vegetation association||prefire||postfire year 1||postfire year 5||prefire||postfire year 1||postfire year 5|
moderate burn (n=4)
severe burn (n=2)
|Subalpine fir/menziesia (Menziesia ferruginea)||
partial burn (n=2)
severe burn (n=2)
A study of different-aged burns in western hemlock-Douglas-fir forests in the Olympic Mountains of Washington revealed stickywilly's preference for recently disturbed forests. The author described past fires as "catastrophic," but no additional information regarding fire season or severity was given. The percent frequency of stickywilly is shown below :
|Time since fire (years)||2||3||19||110||515|
Deciduous forests: Reestablishment of stickywilly following fires in deciduous woodlands is quick. In a red alder woodland in the Oregon Coast Range, sites were clearcut in early spring (March-April), treated with herbicide in June, and burned in early August. The prefire frequency of stickywilly was 15%. Two months following treatments frequency of stickywilly was 0%, and 4 months later stickywilly frequency was 1% .
"Moderately disturbed" upland slippery elm-dominated forests of northern Illinois burned during the 1992 dormant and growing seasons. The dormant season fire burned in March when temperatures averaged 62 °F (16.7 °C), relative humidity was 70%, and the 8 days prior received no precipitation. Approximately 75% to 80% of the unit burned, flame heights measured between 5.9 and 39.4 inches (15-100 cm), and fire spread was 1.3 m/minute. The growing season fire burned in May when temperatures averaged 78 °F (25.6 °C), relative humidity was 29%, and the 9 days prior received no precipitation. Approximately 75%-80% of the unit burned, flame heights were between 4 and 29.5 inches (10-75 cm), and fire spread was 1.7 m/minute. The density of stickywilly decreased on all burned and unburned sites in 1992 and 1993. Stickywilly had not recovered on either burned site by the 3rd postfire year. The prefire and postfire stem densities (per m²) of stickywilly on dormant season burns, growing season burns, and unburned plots are provided below .
|Fire season||dormant (March)||growing (May)||unburned|
|1992||1993||1994||1991 (prefire)||1992||1993||1994||1991 (prefire)||1992||1993||1994|
|Stickywilly stem density (per m²)||4.6||0.1||1.2||0.8||8.4||0.2||0.7||2.7||8.4||1.4||2.0||9.6|
Shrublands/grasslands: In shrubland and grassland fires, stickywilly was commonly present in the 1st postfire community. Following a July wildfire in the chaparral riparian zone of Ventura County, California, stickywilly was present 1, 2, and 3 years following fire . In west-central Utah, a fire burned big sagebrush and Colorado pinyon-Utah juniper (Pinus edulis-Juniperus osteosperma) ecosystems. Stickywilly occurred on 2 plots in the 1st postfire season but was not encountered in the 2nd or 3rd postfire years. The frequency of stickywilly on nearby unburned sites was 0 for all 3 years of postfire sampling . A late July fire in southern California's foothill chaparral vegetation produced surface temperatures of 670 °F (354 °C) and soil temperatures of 156 °F (69 °C) 2 inches (5 cm) below the soil surface. In the preburn community, stickywilly occupied 11 m²; in the 1st year postfire stickywilly occupied 32 m². Researchers indicate that annual forbs were replaced by increasingly dense grasses in the 2nd, 3rd, and 4th postfire years .
An "intense wildfire" burned Gambel oak and big sagebrush/bluebunch wheatgrass communities in the Wasatch Mountains of Utah in August of 1990. Coverage and frequency of stickywilly were greater on burned sites compared to unburned areas. The coverage and frequency (percent of quadrats in which species occurred) of stickywilly on burned and unburned plots is given below :
|Community type||Gambel oak||big sagebrush/bluebunch wheatgrass|
In northeastern Oregon, fires burned in 2 grazing exclosures (1 excluding livestock and game animals, 1 excluding just livestock) within a common snowberry-rose (Rosa spp.) community. The fire was moderately severe: it consumed the litter and woody debris, blackened shrub stems, and charred and partially burned tree trunks. Stickywilly coverage in the 5th postfire year surpassed prefire coverages in both exclosures. Prefire and postfire percent coverage for stickywilly is provided below :
moderate burn/no game or livestock postfire disturbance (n=1)
moderate burn/no livestock postfire disturbance (n=1)
|Time since fire||prefire||1 year||5 yrs||prefire||1 year||5 yrs|
While stickywilly is common in the 1st postfire year in shrub or grassland communities, some studies did not detect stickywilly the 1st season following fire. Following a November, 1994 fire in southern California's chaparral vegetation, stickywilly was not present the 1st postfire growing season. Stickywilly did occur in the 2nd, 3rd, and 4th postfire years . In a rough fescue-dominated grassland near Missoula, Montana, a late June fire burned in 1977. The fire, pushed by gusty winds, consumed virtually all above ground vegetation. The following fall (August and September) received above normal precipitation. Researchers compared burned and nearby unburned sites in the fall, spring, and summer immediately following the fire. Stickywilly was not present on burned sites by the next summer .
The following study presents more long-term fire effects information by comparing burned and unburned Gambel oak communities in central and northern Utah. On unburned sites, the average frequency of stickywilly was 36.8; on burned sites, stickywilly frequency was 33.1. A majority of the burned sites experienced fires 8 years prior, while others burned less than 30 years before initiating the study. Researchers provided no data regarding fire severity or season .
Repeated fires: Stickywilly's probability of recovery from fires seems to decrease as fire frequency increases. In a mixed mesophytic forest of northern Kentucky, sites burned repeatedly. For 2 and 3 consecutive fall seasons, prescription fires with flame heights of up to 5.9 inches (15 cm) burned. The importance of stickywilly was significantly (p<0.05) greater on unburned sites than on sites repeatedly burned . Spring fires (late March-early April) burned annually, biennially, and at 4-, 10-, and 20-year intervals in tallgrass prairie wetlands of northeastern Kansas. The relative importance of stickywilly decreased with increased fire frequency. The relative importance values (%) are provided below. Data are means and 1 standard deviation .
|Fire frequency||10 and 20||2 and 4||annual fires|
|Relative importance value||19.7±3.2||3.5±3.1||0|
Fall and spring prescribed burning in a basin big sagebrush community in east-central Oregon had no significant effect on stickywilly frequency in postfire year 1 or 2 . See the Research Project Summary of this work for more information on fire effects on stickywilly and 60 additional forb, grass, and woody plant species.
These fire studies also provide information on postfire responses of plant species in communities that include stickywilly:
Other mammals: Direct evidence of small mammal use of stickywilly is lacking. In California's Central Valley, 44.5 ringtails/mi2 are estimated to occur in the in riparian areas dominated by Fremont cottonwoods, willows, box elder, black walnut, Douglas' sagewort, California manroot, and stickywilly . Woodrats may feed on stickywilly seeds. Researchers recovered stickywilly seed from 2065- to 2800-year-old woodrat middens in northeastern California and southeastern Oregon . In Picacho Peak, Arizona, 9,400- to 13,100-year-old woodrat middens contained both seeds and leaves .
Birds: Wild turkeys, ring-necked pheasants, Canada geese, and prairie-chickens eat stickywilly seeds [56,143]. However, the stiff, hooked hairs coating the seeds may discourage predation by small birds .
Insects: Several caterpillars including the drab brown wave, common tan wave, and large lace border feed on stickywilly . Likely, many other generalist insects utilize stickywilly.
Palatability/nutritional value: Relatively little information is available on the palatability or nutritional value of stickywilly. On 15-year-old-burn sites in ponderosa pine communities of California's Teaford Forest in the Sierra Nevada, stickywilly contained 1.4% nitrogen .
Cover value: No information is available on this topic.VALUE FOR REHABILITATION OF DISTURBED SITES:
The chemical and mechanical control of stickywilly in cultivated crops is discussed in several studies [21,51,62,91].In natural settings, the presence of stickywilly may give an indication of natural regeneration following disturbances. In southwestern Oregon, stickywilly had an indicator value of 11, suggesting low to moderately low natural regeneration difficulty following clearcutting in mixed conifer and mixed evergreen forests .
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