Symphyotrichum laeve

  © 2005 Robert Sivinski


SPECIES: Symphyotrichum laeve
AUTHORSHIP AND CITATION : Sullivan, Janet. 1992. Symphyotrichum laeve. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: []. ABBREVIATION : SYMLAE NRCS PLANT CODE : SYLA3 COMMON NAMES : smooth blue American-aster smooth aster smooth blue aster purple aster TAXONOMY : The accepted scientific name for smooth blue American-aster is Symphyotrichum laeve (L.) A.& D. Löve.  Recognized varieties are as follows [55,56]: Symphyotrichum laeve var. concinnus (Willd.) Nesom Symphyotrichum laeve var. geyeri (Gray) Nesom Symphyotrichum laeve var. laeve Symphyotrichum laeve var. purpuratus (Nees) Nesom   SYNONYMS : Species name Aster laevis L. [21,22,40,53] Infrataxa Aster laevis var. concinnus (Willd.) House [21,22,40,53] =Symphyotrichum laeve var. concinnus (Willd.) Nesom [55,56] Aster laevis var. geyeri Gray [21,22,40,53]   =Symphyotrichum laeve var. geyeri (Gray) Nesom [55,56] Aster laevis var. guadalupensis A.G. Jones [21,22,40,53]   =Symphyotrichum laeve var. geyeri (Gray) Nesom [55,56] Aster laevis var. laevis [21,22,40,53] =Symphyotrichum laeve var. laeve [55,56] Aster laevis var. purpuratus (Nees) A.G. Jones [21,22,40,53]    =Symphyotrichum laeve var. purpuratus (Nees) Nesom [55,56] LIFE FORM : Forb FEDERAL LEGAL STATUS : None OTHER STATUS : Information on state-level protected status of plants in the United States is available at Plants Database.


SPECIES: Symphyotrichum laeve
GENERAL DISTRIBUTION : Smooth blue American-aster is widely distributed in the United States and Canada from the Atlantic Coast to the eastern slopes of the Cascade Range, south to New Mexico, Texas, and Georgia [19,40,43].  In eastern North America, S. l. var. laeve is the most common.  This variety intergrades in the Great Plains with S. l. var. geyeri.  S. l. var. geyeri's distribution continues through the mountain states to Yukon Territory and British Columbia, eastern Washington and Oregon, south through Utah to New Mexico and Texas [19]. It is cultivated in Hawaii [54].  S. l. var. coccinnus occurs in Georgia, North Carolina, Tennessee, and Virginia [50]. ECOSYSTEMS :    FRES10  White - red - jack pine    FRES12  Longleaf - slash pine    FRES13  Loblolly - shortleaf pine    FRES14  Oak - pine    FRES15  Oak - hickory    FRES18  Maple - beech - birch    FRES19  Aspen - birch    FRES21  Ponderosa pine    FRES36  Mountain grasslands    FRES38  Plains grasslands    FRES39  Prairie STATES :      AL  AZ  CO  CT  DE  GA  HI  ID  IL  IN      IA  KS  KY  LA  ME  MD  MA  MI  MN  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  AB  BC  MB  NB  NF      NS  ON  PE  PQ  SK  YT BLM PHYSIOGRAPHIC REGIONS :     2  Cascade Mountains     4  Sierra Mountains     5  Columbia Plateau     6  Upper 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 :    K011  Western ponderosa forest    K016  Eastern ponderosa forest    K017  Black Hills pine forest    K050  Fescue - wheatgrass    K051  Wheatgrass - bluegrass    K056  Wheatgrass - needlegrass 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    K074  Bluestem prairie    K075  Nebraska Sandhills prairie    K081  Oak savanna    K082  Mosaic of K074 and K100    K084  Cross Timbers    K095  Great Lakes pine forest    K099  Maple - basswood forest    K100  Oak - hickory 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 SAF COVER TYPES :      1  Jack pine     14  Northern pin oak     15  Red pine     16  Aspen     18  Paper birch     19  Gray birch - red maple     20  White pine - northern red oak - red maple     21  Eastern white pine     25  Sugar maple - beech - yellow birch     26  Sugar maple - basswood     27  Sugar maple     42  Bur oak     44  Chestnut oak     46  Eastern redcedar     52  White oak - black oak - northern red oak     53  White oak     70  Longleaf pine     75  Shortleaf pine     78  Virginia pine - oak     79  Virginia pine     83  Longleaf pine - slash pine     84  Slash pine    237  Interior ponderosa pine SRM (RANGELAND) COVER TYPES : NO-ENTRY HABITAT TYPES AND PLANT COMMUNITIES : Smooth blue American-aster is a component of many types of plant associations, most notably of mixed prairie types such as needlegrass (Stipa comata, S. spartea)-blue grama (Bouteloua gracilis) and wheatgrass (Elymus lanceolatus, Pascopyrum smithii)-junegrass (Koeleria cristata) types [10]. Smooth blue American-aster is an understory dominant or a component in a number of quaking aspen (Populus tremuloides) community types, including a quaking aspen-Missouri gooseberry (Ribes missouriense)-roughleaf ricegrass (Oryzopsis asperifolia)-smooth blue American-aster community type [39].  It also occurs as an understory dominant in a quaking aspen-Bigelow ligularia (Ligularia bigelovii) community type [34].  Smooth blue American-aster is a leading dominant in a smooth blue American-aster-western yarrow (Achillea millefolium v. lanulosa) plant association found in openings in quaking aspen parklands [29].


SPECIES: Symphyotrichum laeve
IMPORTANCE TO LIVESTOCK AND WILDLIFE : White-tailed deer will graze smooth blue American-aster, selecting it over other available forbs [14]. PALATABILITY : Smooth blue American-aster is palatable to white-tailed deer and livestock [14,47]. It is likely that it is palatable to other species as well, but documentation is not available. NUTRITIONAL VALUE : Smooth blue American-aster has high nutritional value, decreasing with maturation. Nutritional values for aerial portions are as follows [7]:               digestible protein (%)  cellulose (%)  digestibility(%) leaf stage       11.6                    27.2           77.1 heading           5.9                    28.8           55.2 seed ripening     5.2                    31.2           61.8 COVER VALUE : NO-ENTRY VALUE FOR REHABILITATION OF DISTURBED SITES : Direct seeding of smooth blue American-aster was successful in establishing plants along highway margins for prairie restoration [32].  Smooth blue American-aster is recommended in seedings and plantings for rehabilitation or restoration of native mixed-grass and tallgrass prairies [31,32,49]. OTHER USES AND VALUES : NO-ENTRY OTHER MANAGEMENT CONSIDERATIONS : In a study of prairie regeneration in which herbicides were applied to control quackgrass (Agropyron repens), smooth blue American-aster failed to establish in plantings treated with either glyphosate or dichlobenil [49]. Picloram, tebuthiuron, and hexazinone all suppressed growth of smooth aster, either alone or in combination.  Applied alone, 2,4,D-E did not suppress smooth blue American-aster growth [31]. Grazing by deer does not appear to affect survival of established plants or seedlings, as long as only the stem tips are removed.  Most plants damaged by deer responded with vigorous growth the following season [14].  Weaver and Hansen [47] classify smooth blue American-aster as a decreaser under grazing. Plants grown under nursery conditions had excellent rates of survival when planted in the field.  Nursery stock was planted at a rate of 3.5 ounces of seed per 100 square feet (11 gm/sq m), and resulted in a harvest of 9.5 pounds of seed per 100 square feet (0.5 kg/sq m) [46].


SPECIES: Symphyotrichum laeve
GENERAL BOTANICAL CHARACTERISTICS : Smooth blue American-aster is a moderately tall (12 to 40 inches [30 -100 cm]) native perennial forb, with a stout rhizome and branching caudex.  There are one to several erect stems.  The fruit is a one-seeded achene [14,19,36]. RAUNKIAER LIFE FORM :    Hemicryptophyte    Geophyte REGENERATION PROCESSES : Smooth blue American-aster reproduces well from seed.  Seeds do not require either scarification or stratification [20,32].  Greenhouse germination trials showed that, without stratification, initial germination occurs at 7 days, and peak germination occurs at 20 days [32].  Seed banking is not apparent; soil samples collected in August (probably before seed release) contained no germinable smooth blue American-aster seeds [37]. SITE CHARACTERISTICS : Smooth blue American-aster occurs on a wide variety of sites, including moist, sandy soil in woods, dry woods, and open areas, and mesic and dry-mesic prairies [30,40].  Cover and frequency of smooth blue American-aster is highest on sites with high light intensities, though it occurs on more shaded sites as well [41].  It usually sustains higher populations on wetter, more poorly drained glacial till soils in eastern Illinois and western Indiana [6].  In Michigan, however, Beaufait [4] reported that although smooth blue American-aster occurs on mesic and transitional sites, it is more likely to be encountered on the more xeric sites. Elevation occurrence data from selected western states is as follows [12]:                feet             meters Utah        5,700 - 8,600    1,737 - 2,621 Colorado    5,000 - 9,300    1,524 - 2,835 Wyoming     3,700 - 7,600    1,128 - 2,316 Montana     2,300 - 6,000      701 - 1,829 SUCCESSIONAL STATUS : Facultative Seral Species Thirty years after study plots had been retired from heavy grazing, smooth blue American-aster was found only on the edges of the sites nearest undisturbed native prairie [18].  Smooth blue American-aster is found on roadsides and other previously disturbed areas but is probably not an initial colonizer. Smooth blue American-aster is probably not tolerant of deep shade but will tolerate light or intermittent shade. SEASONAL DEVELOPMENT : Smooth blue American-aster blooms from August to October [11].  The lowermost leaves are early deciduous; the remaining leaves are dropped after frost top-kills the plant [19].


SPECIES: Symphyotrichum laeve
FIRE ECOLOGY OR ADAPTATIONS : Smooth blue American-aster sprouts from the rhizome after being top-killed by fire. It occurs in a number of plant associations that have frequent fire regimes.  Presumably, it is adapted to fire, though no specific information is available in the literature. In general, forbs are more adversely affected by fires that occur later in the spring.  Usually cover is reduced, while overall composition remains little affected.  Forbs are much less affected by dormant-season fires than by spring fires [8]. POSTFIRE REGENERATION STRATEGY :    Rhizomatous herb, rhizome in soil    Ground residual colonizer (on-site, initial community)    Secondary colonizer - off-site seed


SPECIES: Symphyotrichum laeve
IMMEDIATE FIRE EFFECT ON PLANT : Fire top-kills smooth blue American-aster. DISCUSSION AND QUALIFICATION OF FIRE EFFECT : NO-ENTRY PLANT RESPONSE TO FIRE : Most reports on the effects of fire in communities occupied by smooth aster are inconclusive as to its response [1,17].  The number of leaves per individual plant increased following a late spring prescribed fire, with no change in the number of flowers or fruit per individual for either the early spring or late spring prescribed fires [27]. Prescribed spring fires had variable effects on flowering in smooth aster, depending on habitat.  Flowering was inhibited on dry-mesic prairie site on an undisturbed south-facing slope and on a highly disturbed, level, mesic prairie site.  Flowering was stimulated on sloping and level mesic undisturbed prairie sites [33].  Three years after a wildfire in jack pine (Pinus banksiana) stands, smooth blue American-aster was an important component of the regenerating plots.  These sites had standing dead trees, which indicates that there was probably a substantial loss of crown shading [2]. Smooth blue American-aster was listed as a decreaser under an annual early spring burning regime, and also after a spring wildfire [3,44].  Scheiner [37] reported the presence of smooth blue American-aster on sites that had recently undergone prescribed burns, as well as on older postfire seral sites. DISCUSSION AND QUALIFICATION OF PLANT RESPONSE : NO-ENTRY FIRE MANAGEMENT CONSIDERATIONS : NO-ENTRY

References: Symphyotrichum laeve

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