(DRAFT) - Taxonomy
Species ASTER, GOLDEN, RUTH'S
Species Id ESIS704019
Date 13 MAR 96
TAXONOMY
NAME - ASTER, GOLDEN, RUTH'S
OTHER COMMON NAMES - ASTER, GOLDEN and RUTH'S
ELEMENT CODE -
CATEGORY - Angiosperm
PHYLUM AND SUBPHYLUM - MAGNOLIOPHYTA,
CLASS AND SUBCLASS - MAGNOLIOPSIDA,
ORDER AND SUBORDER - ASTERALES,
FAMILY AND SUBFAMILY - ASTERACEAE,
GENUS AND SUBGENUS - PITYOPSIS,
SPECIES AND SSP - RUTHII,
SCIENTIFIC NAME - PITYOPSIS RUTHII
AUTHORITY -
TAXONOMY REFERENCES -
COMMENTS ON TAXONOMY -
Ruth's Golden Aster
Pityopsis ruthii (Small) Small
KINGDOM: Plant GROUP: Angiosperm
DIVISION: Magnoliophyta CLASS: Magnoliopsida
ORDER: Asterales FAMILY: Asteraceae
The following is a non-technical description of Pityopsis ruthii
(Ruth's golden aster) (19).
Ruth's golden aster is an extremely rare endemic known only from
phyllite boulders in and adjacent to the Hiwassee and Ocoee Rivers in
Polk County Tennessee. It has clustered, upright stems (to 1 foot
high), narrow, silvery, gray-green, grasslike leaves from a woody
rootstock and yellow aster-like flowering heads supported by leafless
stalks (0.5-2 in long) covered with tiny yellowish gland-tipped
hairs. The fruiting heads strongly resemble dandelions but are only
about half the size.
The following is a technical description of Ruth's Golden Aster
(19).
HABIT: Fibrous-rooted perennial with clustered stems 1-3 dm tall,
silvery-sericeous, 1-many terminal, yellow-flowered pedunculate
inflorescences/stems. STEMS: Erect, clustered, few to many, 1-3 dm
Taxonomy - 1 (DRAFT) - Taxonomy
Species ASTER, GOLDEN, RUTH'S
Species Id ESIS704019
Date 13 MAR 96
high from woody rhizomatus base 1.5-3 mm thick; silvery-sericeous
above, browm glabrate beneath. LEAVES: Alternate, sessile,
gray-green, numerous, overlapping, ascending-spreading; linear to
lanceolate, 3-5 cm long, 2-4.5 mm wide; midvein apparent; both
surfaces silvery-sericeous; margins entire. Lower cauline leaves
withering to deciduous in late summer; basal leaves when present,
similar to cauline leaves. INFLORESECENCE: 1-several pedunculate
involucrate heads, terminal or axillary from the upper leaves;
peduncles 0.5-4 cm long, 0.6-1 mm wide, densely stipitate-glandular,
glands pale yellowish; 0-3 short lancolate bracteoles 2-9 mm long
subtending the heads. FLOWERS: Ray and disc in heads 5-8 mm wide,
6-8 mm high; involucre of 4-6 series; bracts ascending, inner surface
smooth, outer surface with sessile to stipitate glands, tufted ciliate
at tip, with a narrow scarious, hyaline margin; ray flowers yellow,
8-14/head, yellow, weakly toothed apically, pubescent on tube and back
of limb, 6-10 mm long, 2-2.5 mm wide, pistillate and fertile, style
branches glabrous; disc flowers yellow, up to 45/head, 4.5-6.0 mm
long, perfect and fertile, style branches puberulent; pappus double,
outer scalelike, minute, inner of antrorsely barbed capillary
bristles; achenes fusiform, 2-3 mm long, with 6-8 ribs, pubsecence
ascending-pilose. N=9. Other descriptions of this species may be
found in references 02, 04, 12, and 14.
A nomenclatural description as well as sources for specimens,
photographs, and drawings of Ruth's golden aster is as follows:
Ruth's golden aster was originally described by Small (14) as
Chrysopsis ruthii in 1897. In 1933, Small (11) transferred this
species to the genus Pityopsis. An additional transfer was effected
by Harms (10) to the genus Heterotheca in 1969. The most recent
taxonomic treatment (12) adopts the combination Pityopsis ruthii
(Small) Small. It has been treated by others under the genera
Chrysopsis (04) and Heterotheca (02,17,19).
The type specimen (presumably the holotype) is on deposit at the
New York Botanical Garden (NY), Bronx, NY (02,12). Additional and
representative specimens are located at CU, FSU, GH, MO, NCU, TENN, US
(02) and WAT (12). Line drawings may be found in Semple and Bowers
1985 (12) and Wofford and Smith 1980 (19). Photographs may be found
in Bowers 1972 (02) and U.S. Department of Agriculture 1981 (16).
Taxonomy - 2 (DRAFT) - Status
Species ASTER, GOLDEN, RUTH'S
Species Id ESIS704019
Date 13 MAR 96
STATUS
Coded Status
Tennessee; Federal Endangered
Tennessee; State Listed
E: Federal Endangered
Ornamental
COMMENTS ON STATUS -
U.S. STATUSES AND LAWS:
Pityopsis ruthii (Ruth's golden aster) has been designated an
Endangered species pursuant to the Endangered Species Act of 1973, as
amended (50 CFR, Sec. 17.12). The species has this status wherever
found including the State of Tennessee. This species is also
protected by the Lacey Act, as amended in 1981. Under this Act it is
prohibited to import, export, sell, receive, acquire, purchase or
engage in the interstate or foreign commerce of any plant taken,
possessed, or sold in violation of any law, or any law or regulation
of any State. It is unlawful to remove and reduce to possession any
endangered or threatened plant from an area under Federal jurisdiction
(50 CFR 17.61(c) and 17.71(a)).
RESPONSIBLE FEDERAL AGENCIES:
USFWS -Responsible for the management/recovery, listing, and
law enforcement/protection of this species.
USFS -Responsible for the law enforcement/protection of this
species with applicable State and Federal laws on
public lands under their control. Also responsible
for management/recovery on Forest Service lands.
Forest Service regulations prohibit the removal,
destruction, or damaging of any plant classified as
threatened, endangered or rare (36 CFR 261).
TVA -Responsible for the management/recovery, listing, and
law enforcement/protection of this species.
All Federal agencies have responsibility to ensure that any
action authorized, funded, or carried out by that agency is not likely
to jeopardize the continued existence of the species and to utilize
their authorities to carry out programs for the conservation of the
species.
STATE STATUSES AND LAWS:
STATE: Tennessee
DESIGNATED STATUS: Endangered
ADMINISTRATIVE AGENCY: Tennessee Department of Conservation
STATE STATUTE: The Rare Plant Protection and Conservation Act of
1985 (Chap. 0400-6-2-.01 et seq.).
INTERNATIONAL STATUSES, TREATIES, AND AGREEMENTS:
Status - 1 (DRAFT) - Status
Species ASTER, GOLDEN, RUTH'S
Species Id ESIS704019
Date 13 MAR 96
None.
ECONOMIC STATUSES:
This attractive Composite has potential for horticultural use as
a rock-garden plant.
75/07/01:40 FR 27824/27924 - Notice of review of status
76/06/16:41 FR 24524/24572 - Proposed rule, list as Endangered
79/12/10:44 FR 70796/ - Withdrawal of proposed rule
80/12/15:45 FR 82480/82569 - Notice of review of taxa
83/11/28:48 FR 53640/53670 - Supplement to review of taxa
84/11/20:49 FR 45766/45769 - Proposed rule, list as Endangered
85/07/18:50 FR 29341/29345 - Final rule, list as Endangered
Status - 2 HABITAT ASSOCIATIONS
HABITAT - TERRESTRIAL
INLAND AQUATIC
LAND USE -
Bare Exposed Rock
Transportation, communications, and Util
Streams and Canals
NATIONAL WETLAND INVENTORY CODES
NWI NWICLS NWIMOD NWISPEC
Riverine, upper perennial RS2
COMMENTS ON HABITAT ASSOCIATIONS -
Pityopsis ruthii (Ruth's golden aster) is endemic to unique
riparian/inland aquatic areas of bare, exposed phyllite rock crevices
in and along the Ocoee and Hiwassee Rivers (17,19). These areas are
situated within Ecoregion/Appalachian Oak Forest. Known environmental
parameters indicate that P. ruthii does not occur where light
intensities are less than 50 percent of full sunlight. Rock surface
temperatures frequently exceed 43 deg. C during mid-summer. Plants
are rooted in boulder crevices filled with fine textured sandy-loam
soils of ca. 72 percent sand, 25 percent silt, and 3 percent clay.
Soil moisture conditions at mean field capacity reach 25 percent at
0.33 bars pressure. Chemical characterization of soil is fairly low in
pH (pH 4.8), low to medium concentrations of available nitrogen,
phosphorus, potassium, magnesium, and calcium; and high concentrations
of zinc, manganese, iron, and copper (17,19).
Pityopsis ruthii occupies a narrowly defined, non-successional,
xeric habitat. Its restriction to dry, exposed boulder crevices
selectively excludes most potential competitors except for Liatris
microcephala, Andropogon ternarius, and Aster linariifolius (17,19).
Riparian communities adjacent to these sites are dominated by Cornus
amomum, Salix caroliniana, S. nigra, Platanus occidentalis,
Liquidamber styraciflua, Acer rubrum, Alnus serrulata, Rhus radicans,
Parthenocissus quinquefolia, and Campsis radicans (19). No data are
available on community structure or successional trends/threats from
adjacent vegetation to Pityopsis ruthii habitat (21). It is uniquely
adapted for survival in habitats unfavorable to competition; and this
habitat appears to be stable, having supported populations with low
turnover for long periods of time (21).
The Louisville and Nashville Railroad line parallels the Hiwassee
River population. Train derailments have resulted in chemical spills
that have impacted the population.
Habitat Associations - 1 (DRAFT) - Food Habits
Species ASTER, GOLDEN, RUTH'S
Species Id ESIS704019
Date 13 MAR 96
FOOD HABITS
TROPHIC LEVEL -
AUTOTROPH
Food Habits - 1 (DRAFT) - Environment Associations
Species ASTER, GOLDEN, RUTH'S
Species Id ESIS704019
Date 13 MAR 96
ENVIRONMENTAL ASSOCIATIONS
G = General A = Adult
LIM = Limiting RA = Resting Adult
J = Juvenile FA = Feeding Adult
RJ = Resting Juvenile BA = Breeding Adult
FJ = Feeding Juvenile P = Pupae
L = Larvae E = Egg
RL = Resting Larvae
FL = Feeding Larvae
LIFESTAGE ENVIRONMENTAL ASSOCIATIONS
G Terrestrial Features: Rock outcrops
G
G
Environment Associations - 1 (DRAFT) - Life History
Species ASTER, GOLDEN, RUTH'S
Species Id ESIS704019
Date 13 MAR 96
LIFE HISTORY
HABIT:
Ruth's golden aster (Pityopsis ruthii) is herbaceous (02,04,12,14
15,17,19,20).
LIFE CYCLE:
Perennial (02,04,12,14,15,17,19,20).
TYPE OF REPRODUCTION:
Sexual and vegetative (17,19). Asexual reproduction appears the
principle instrument for maintaining current populations (19,21). No
seedling stages have been observed or reported for either the Hiwassee
or Ocoee river populations (17,19,20) although viable seeds are known
to be produced and plants have been successfully cultivated to
flowering and seed set (05,17).
REPRODUCTIVE PHENOLOGY:
Leafing occurs in March, budding from August to September,
anthesis from August to early October, and fruiting and seed dispersal
from September to October (05,17,19,12,02).
SEX OR SPORE STATUS:
Polygynous (21). Gynomonecious is the more exact descriptor for
P. ruthii which bears both perfect and pistillate flowers in each
flowering head.
POLLINATION, SPORE AND SEED DISSEMINATION:
Pollen dissemination agents and seed dissemination agents are
unknown/unverified. Pollen dissemination is speculated to be wind
and/or non-selective insect foraging (19), while seed dissemination
agents are assumed to be wind and water (21).
SEED BIOLOGY:
Some aspects of pollination and seed biology of Pityopsis ruthii
have been investigated. Pollen viability, as measured by staining
techniques, indicates an average percent stainability of 96.4 percent
(02). No report on mechanisms for pollen transport has been
published, but it is reasonable to assume that a combination of wind
and non-selective insect foraging might account for low values of seed
set in natural populations (19). Dispersal of seeds is probably by
wind or water, but effective dispersal by actual accounts of seedling
presence is apparently rare. Numbers of filled achenes per head in
both natural and greenhouse-grown populations are low. The Hiwassee
populations averaged 50 achenes/head, of which only 9 (18 percent)
proved to be filled. Experimental populations produced an average of
11 filled seeds/head (19 percent) (17). A replicate study of Hiwassee
populations reported an average of only 5 percent filled seeds/head
compared to nursery-grown plants which showed an increase to 12
percent filled seeds/head (05). Further studies on seed biology and
development (05) indicate the best germination (90 percent) occurred
between 7-24 deg. C during a 10-day period. At temperatures ranging
from 24-29 deg. C the percent germination dropped to 70 percent over
Life History - 1 (DRAFT) - Life History
Species ASTER, GOLDEN, RUTH'S
Species Id ESIS704019
Date 13 MAR 96
an extended 20 day period. Seeds stored at 3 deg. C for six months
showed a 15 percent decrease in germination when tested under the
optimum temperature range. Of the seedlings which passed through the
cotyledonary state, 80-90 percent survived to maturity (05,19).
POPULATION BIOLOGY:
Early, cursory estimates of the total population of Pityopsis
ruthii (Ruth's golden aster) are circa 1000 plants including both
Hiwassee and Ocoee River systems (17,18,19). A recent completed study
(08) has mapped and counted 593 plants in eight sites along the Ocoee
River; and more than 900 plants distributed in more than eight sites
along the Hiwassee River. No data are available for population
trends, causes of mortality, or recovery potential (21).
ECOLOGICAL/EDAPHIC FACTORS:
Pityopsis ruthii occurs exclusively on barren phyllite boulders
of the Walden Creek and Great Smokey Groups of Precambrian age rocks
(17,19,09). The plants are rooted in fine textured, relatively
fertile, sandy-loam soils that accumulate in cracks and fissures of
the phyllite boulders (17,19). Soil characterization and analysis
reveals a consistency of 72 percent sand, 25 percent silt, 3 percent
clay, low to medium concentrations of macronutrients, high
concentrations of micronutrients, pH 4.8, and field capacity of 25
percent soil moisture at 0.33 bars pressure (17,19). Specific
microclimate site factors would indicate that insolation must exceed
50 percent of full sunlight, which may account for greater than 90
percent of the populations that occur on southern exposures (08,17,
19). High incident radiation may elevate surface temperatures of the
phyllite boulders to as much as 43 deg. C (17,19). Species hardiness
to such high temperatures may exclude competitors from these sites
(21).
TROPHIC STATUS:
Phototrophic.
CHARACTERISTIC DOMINANCE:
Component (17,19). Pityopsis ruthii populations occupy sparsely
populated sites in both river systems with few or no competitors.
Within sites, individual plants are multi-stemmed and plants are
rarely crowded and never shade one another. Interplant distances are
dictated by the pattern of cracks and fissures in the phyllite
boulders (08,17,19,21)
COMMUNITY ECOLOGY:
Pityopsis ruthii occupies a narrowly defined, non-successional,
xeric habitat. Its restriction to dry, exposed boulder crevices
selectively excludes most potential competitors except for Liatris
microcephala, Andropogon ternarius, and Aster linariifolius (17,19).
Riparian communities adjacent to these sites are dominated by Cornus
amomum, Salix caroliniana, S. nigra, Platanus occidentalis,
Liquidamber styraciflua, Acer rubrum, Alnus serrulata, Rhus radicans,
Parthenocissus quinquefolia, and Campsis radicans (19). No data are
available on community structure or successional trends/threats from
Life History - 2 (DRAFT) - Life History
Species ASTER, GOLDEN, RUTH'S
Species Id ESIS704019
Date 13 MAR 96
adjacent vegetation to Pityopsis ruthii habitat (21). It is uniquely
adapted for survival in habitats unfavorable to competition; and this
habitat appears to be stable, having supported populations with low
turnover for long periods of time (21).
SPECIES INTERRELATIONSHIPS:
No information available.
OTHER LIFE HISTORY DESCRIPTORS:
No information available.
Life History - 3 (DRAFT) - Management Practices
Species ASTER, GOLDEN, RUTH'S
Species Id ESIS704019
Date 13 MAR 96
MANAGEMENT PRACTICES
RESULT MANAGEMENT PRACTICE
Beneficial Restricting/regulating human disturbance of populations
Beneficial Maintaining/Controlling Water Flow
Beneficial Maintaining Early Stages of Succession
Beneficial Controlling/Removing Native Vegetation
Beneficial Stocking captive-reared wild-strain animals
Beneficial Maintaining Sperm/Seed Banks
Beneficial Transplanting Wild Eggs/Wild Seeds
Adverse Incidental Capturing/Killing
Existing Incidental Capturing/Killing
Adverse Rock Climbing
Existing Rock Climbing
Adverse Hiking/Camping
Existing Hiking/Camping
Adverse Inherent Reproductive Characteristics
Existing Inherent Reproductive Characteristics
Adverse Surface Mines
Existing Surface Mines
Adverse Siltation
Existing Siltation
Adverse Water Level Fluctuation
Existing Water Level Fluctuation
Adverse Environmental Contamination/Pollution
Existing Environmental Contamination/Pollution
Adverse Competition
Existing Competition
COMMENTS ON MANAGEMENT PRACTICES -
Ruth's golden aster is a narrow endemic restricted to phyllite
boulders along the Ocoee and Hiwassee Rivers. Its total known range
is limited to a combined 6.5 river miles of these riparian systems
(17,18,19,20).
Present threats to both populations include: competition by
vegetation encroachment resulting from altered natural water flow
cycles created by Tennessee Valley Authority dam controls on both
rivers; inherently low seed production; and little or no seedling
establishment. Past impacts to the Hiwassee River population are
occassional chemical spills (sulphuric acid) from train derailments.
Impacts to the Ocoee River population have been and continue to be
more severe. Since the mid-1800's, the Ocoee River has been severely
polluted from mining activities in the Copperhill area, resulting in
chemical toxification, acidification, and siltation. Intensive
recreational use of the channel by commercial and private white-water
enthusiasts may be creating a threat of uncertain magnitude. Boaters
use boulders in and along both rivers for recreation, frequently
trampling and picking plants (07,17,19).
UNAPPROVED PLAN:
Management Practices - 1 (DRAFT) - Management Practices
Species ASTER, GOLDEN, RUTH'S
Species Id ESIS704019
Date 13 MAR 96
A recovery plan has not yet been initiated.
The first task which must be completed is the preparation of a
recovery plan for Ruth's golden aster (Pityopsis ruthii). Searches in
adjacent watersheds for additional populations is recommended. Only a
limited amount of searching has been done in these areas. Permanent
plots within each population must be established and regularly
monitored. The biotic and abiotic factors of the species habitat must
be determined, with special attention directed towards obtaining a
better understanding of the role water levels play in maintaining the
species habitat. Demographic studies must be completed. A seed bank
for each population should be established. Captive propagation and
reintroduction may be viable and necessary management tools. Limiting
human access and disturbance to P. ruthii habitats may also be
necessary. Management guidelines for each population must be
developed. Management practices needed to insure the continued
existence of this species must be implemented (with the cooperation of
the U.S. Forest Service and the Tennessee Valley Authority).
Management might include maintaining early successional stages and
removal of encroaching vegetation since the species requires full
sunlight. Maintenance of optimum water flow of the river systems may
also be necessary.
Management Practices - 2 (DRAFT) - References
Species ASTER, GOLDEN, RUTH'S
Species Id ESIS704019
Date 13 MAR 96
References
***** REFERENCES FOR ALL NARRATIVES EXCEPT N-OCCURRENCE *****
01 Bowers, F.D. 1972. The existence of Heterotheca ruthii
(Compositae). Castanea 37:130-132.
02 Bowers, F.D. 1972. A biosystematic study of Heterotheca sect.
Pityopsis. Ph.D. diss., Univ. of Tenn., Knoxville. 188 pp.
03 Cronquist, A. 1968. The evolution an classification of flowering
plants. Houghton Mifflin Co., Boston, MA.
04 Cronquist, A. 1980. Vascular flora of the southeastern United
States. Vol. I: Asteraceae. Univ. of N.C. Press, Chapel Hill.
05 Farmer, R.E. 1977. Seed propagation of Heterotheca ruthii.
Castanea 42:146-148.
06 U.S. Fish and Wildlife Service. 1980. Endangered and threatened
wildlife and plants: Review of taxa for listing as endangered or
threatened species. Fed. Reg. 45(242):82480-82569.
07 U.S. Fish and Wildlife Service. 1985. Endangered and threatened
wildlife and plants; determination of endangered status for
Pityopsis ruthii (Ruth's Golden Aster). Fed. Reg. 50(138):
29341-29345.
08 Haggard, D. 1985. Heterotheca ruthii (Small) Harms. Tech. Rep.,
TN Dept. of Conservation, Nashville. 11 pp. + maps.
09 Hardeman, W.D. 1966. Geologic map of Tennessee. East-central
sheet. TN Div. of Geology, Nashville.
10 Harms, V.I. 1969. A preliminary conspectus of Heterotheca sect.
Pityopsis (Compositae). Castanea 34:402-409.
11 Kartesz, J.Y. and R. Kartesz. [n.d.] A synonymized checklist of
the vascular flora of the United States, Canada, and Greenland.
Vol. II. The biota of North America. Univ. of NC Press, Chapel
Hill.
12 Semple, J.C. and F.D. Bowers. 1985. A revision of the goldenaster
genus Pityopsis Nutt. (Compositae: Asteraceae). Univ. of Waterloo
Biology Series 29:1-34.
13 Semple, J.C., V.C. Blok, and P.P. Heiman. 1980. Morphological,
anatomical, habit and habitat differences among the golden aster
general Chrysopsis, Heterotheca, and Pityopsis
(Compositae-Asteraceae). Can. J. Bot. 58:147-163.
14 Small, J.K. 1897. Studies in the botany of the southeastern
United States. XII. Bull. Torrey Bot. Club 24:493.
15 Small J.K. 1933. Manual of the southeastern flora. J.K. Small,
New York.
16 U.S. Dept. of Agriculture. 1981. Sensitive plants of the Cherokee
National Forest. U.S. For. Serv., Southern Region. 31 pp.
17 White, A.J. 1977. An autecological study of the proposed
endangered species, Heterotheca ruthii (Small) Harms. M.S. Thesis,
Univ. of Tennessee, Knoxville. 73 pp.
18 White, A.J. 1978. Range extensions of the proposed endangered
plant, Heterotheca ruthii (Compositae). Castanea 43:263.
19 Wofford, B.E., and D.K. Smith. 1980. Status report for
Heterotheca ruthii (Ruth's golden aster). Unpubl. rep., contracted
for the U.S. Fish & Wildl. Serv., Atlanta, GA. 33 pp.
20 Wofford, B.E., and D.K. Smith. 1980. Heterotheca ruthii (Small)
References - 1 (DRAFT) - References
Species ASTER, GOLDEN, RUTH'S
Species Id ESIS704019
Date 13 MAR 96
Harms. IN: Inventory of proposed threatened and endangered
species--Cherokee National Forest, Tennessee. B.E. Wofford, ed.
Unpubl. rep. contracted for the U.S. For. Serv., Atlanta, GA.
7 pp.
21 Wofford, B.E., and D.K. Smith. 1986. Unpublished data.
***** REFERENCES FOR N-OCCURRENCE NARRATIVE ONLY *****
01 Bailey, R.G. and C.T. Cushwa. 1982. Ecoregion, land-surface form
and hydorlogic unit maps of the United States. U.S. Dept. of the
Interior, Fish and Wildlife Service, Washington, D.C.
02 Bowers, F.D. 1972. The existence of Heterotheca ruthii
(Compositae). Castanea 37:130-132.
03 Bowers, F.D. 1972. A biosystematic study of Heterotheca sect.
Pityopsis. Ph.D. diss., Univ. of Tennessee, Knoxville. 188 pp.
04 Hydrologic Unit Map. 1974. State of Tennessee 1:500,000. U.S.
Geological Survey, Reston, Virginia.
05 Small, J.K. 1897. Studies in the botany of the southeastern
United States. Volume XII. Bull. Torrey Bot. Club 24:493.
06 White, A.J. 1977. An autecological study of the proposed
endangered species, Heterotheca ruthii (Small) Harms. M.S. Thesis,
Univ. of Tennessee, Knoxville. 73 pp.
07 White, A.J. 1978. Range extensions of the proposed endangered
plant, Heterotheca ruthii (Compositae). Castanea 43:263.
08 Wofford, B.E. and D.K. Smith. 1980. Status report for Heterotheca
ruthii (Ruth's Golden Aster). Unpubl. rep., contracted for the
U.S. Fish & Wildlife Service, Atlanta, Georgia. 33 pp.
References - 2