Introductory
SPECIES: Rhododendron calendulaceum | Flame Azalea 



ABBREVIATION : 
RHOCAE

SYNONYMS : 
   Azalea calendulacea Michx. [8,20]


SCS PLANT CODE : 
   RHCA4


COMMON NAMES : 
   flame azalea


TAXONOMY : 
The currently accepted scientific name for flame azalea is Rhododendron
calendulaceum (Michx.) Torr. (Ericaceae) [8,20].  There are no currently
accepted infrataxa.


LIFE FORM : 
Shrub

FEDERAL LEGAL STATUS : 
See OTHER STATUS

OTHER STATUS : 
The status of flame azalea in New York and Maryland is undetermined.
Although historically reported in these states, no extant populations
are known [3,30].  Flame azalea is listed as endangered in Ohio [13].
It is secure throughout the rest of its range.


COMPILED BY AND DATE : 
Jennifer H. Carey, July 1994


LAST REVISED BY AND DATE : 
NO-ENTRY


AUTHORSHIP AND CITATION : 
Carey, Jennifer H. 1994. Rhododendron calendulaceum. In: Remainder of Citation

DISTRIBUTION AND OCCURRENCE
SPECIES: Rhododendron calendulaceum | Flame Azalea 



GENERAL DISTRIBUTION : 
Flame azalea occurs in the Appalachian Mountains from southern
Pennsylvania and southeastern Ohio south to northern Georgia and
northern Alabama [8,20,28].  Historically it has been reported as far
north as southeastern New York [30].


ECOSYSTEMS : 
   FRES13  Loblolly - shortleaf pine
   FRES15  Oak - hickory
   FRES18  Maple - beech - birch


STATES : 
     AL  GA  KY  NC  OH  PA  SC  TN  VA  WV


ADMINISTRATIVE UNITS : 
     BLRI  CHCH  GRSM  NERI  SHEN


BLM PHYSIOGRAPHIC REGIONS : 
NO-ENTRY


KUCHLER PLANT ASSOCIATIONS : 
   K104  Appalachian oak forest
   K109  Transition between K104 and K106
   K111  Oak - hickory - pine forest


SAF COVER TYPES : 
    44  Chestnut oak
    52  White oak - black oak - northern red oak
    53  White oak
    55  Northern red oak


SRM (RANGELAND) COVER TYPES : 
NO-ENTRY


HABITAT TYPES AND PLANT COMMUNITIES : 
Flame azalea occurs in mixed deciduous forests [11,19,26].  It occurs in
the well developed shrub layer of oak (Quercus spp.) forests of southern
and western exposures, and with more mesic site species in ravines.
Flame azalea is an important understory shrub in forests formerly
codominated by American chestnut (Castanea dentata) [1,26].

Flame azalea occurs with other ericaceous shrubs including rosebay
rhododendron (Rhododendron maximum), mountain-laurel (Kalmia latifolia),
highbush cranberry (Vaccinium corymbosum), and huckleberry (Gaylussacia
spp.) [1].  It occurs at low coverage in the grassy bald vegetation type
and the grassy bald edge ecotone [26].

VALUE AND USE
SPECIES: Rhododendron calendulaceum | Flame Azalea 



WOOD PRODUCTS VALUE : 
NO-ENTRY


IMPORTANCE TO LIVESTOCK AND WILDLIFE : 
NO-ENTRY


PALATABILITY : 
NO-ENTRY


NUTRITIONAL VALUE : 
NO-ENTRY


COVER VALUE : 
NO-ENTRY


VALUE FOR REHABILITATION OF DISTURBED SITES : 
NO-ENTRY


OTHER USES AND VALUES : 
Flame azalea is considered one of the finest ornamental shrubs in the
United States [14].


MANAGEMENT CONSIDERATIONS : 
Many nursery cultivars have been developed from flame azalea.  It is
highly sought after for its striking colors and relative cold hardiness
[17,18].  In states where flame azalea is rare, illegal collection is a
threat [13].

BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Rhododendron calendulaceum | Flame Azalea 



GENERAL BOTANICAL CHARACTERISTICS : 
Flame azalea is a native, deciduous, erect, much-branched shrub that
grows to 10 feet (3 m) in height.  Its morphology and phenology are
highly variable [28].  The fruit is a capsule [8,20,29].  Rhododendrons
(Rhododendron spp.) have a diffuse shallow root system [22].  Flame
azalea is not rhizomatous [8].


RAUNKIAER LIFE FORM : 
   Phanerophyte


REGENERATION PROCESSES : 
Rhododendron fruits split along the sides soon after ripening and
release many small seeds which are disseminated short distances by
wind.  Moist mineral soil or a short moss seedbed is required for
seedling establishment [9,16].

Rhododendrons sprout from the root crown when top-killed [9].

Propagation techniques from cuttings are described [5,23].  Day-night
temperatures and durations for maximizing flame azalea seedling growth
are reported [12].


SITE CHARACTERISTICS : 
Flame azalea occurs on south- and west-facing slopes of mountainous
sites.  It occurs on submesic to subxeric sites at lower elevations and
on submesic sites at elevations above 5,000 feet (1,500 m) [26].
Adequate humidity and soil moisture are required.  Rhododendrons grow
best on acidic soils from pH 4.5 to 5.5 [4].


SUCCESSIONAL STATUS : 
Facultative Seral Species

Flame azalea is intermediate in shade tolerance.  It grows well in the
indirect light of open woods but declines as forests mature and canopies
close [13].


SEASONAL DEVELOPMENT : 
Flame azalea flowers in late April and May at lower elevations and in
June and early July at higher elevations [28].  Flowers appear before or
with the leaves and last several weeks.  Fruit matures July through
September [2,8,20,29].

FIRE ECOLOGY
SPECIES: Rhododendron calendulaceum | Flame Azalea 



FIRE ECOLOGY OR ADAPTATIONS : 
Flame azalea is probably fire resistent because of its ability to sprout
from the root crown.  Fire may open up maturing forest canopies and
rejuvenate declining flame azalea.  Flame azalea occurs in oak woods
that periodically experience fire [27].


POSTFIRE REGENERATION STRATEGY : 
   Tall shrub, adventitious-bud root crown

FIRE EFFECTS
SPECIES: Rhododendron calendulaceum | Flame Azalea 



IMMEDIATE FIRE EFFECT ON PLANT : 
Rhododendrons are sensitive to fire [9].  Fire probably top-kills
flame azalea.


DISCUSSION AND QUALIFICATION OF FIRE EFFECT : 
NO-ENTRY


PLANT RESPONSE TO FIRE : 
Flame azalea probably sprouts from the root crown when top-killed.


DISCUSSION AND QUALIFICATION OF PLANT RESPONSE : 
NO-ENTRY


FIRE MANAGEMENT CONSIDERATIONS : 

REFERENCES
SPECIES: Rhododendron calendulaceum | Flame Azalea 



REFERENCES : 

 .  Braun, E. L. 1950. Deciduous forests of eastern North America.
       Philadelphia, PA: The Blakiston Co. 596 p.  [19637]

 .  Braun, E. Lucy. 1961. The woody plants of Ohio. Columbus, OH: Ohio State
       University Press. 362 p.  [12914]

 .  Broome, C. Rose; Reveal, James L.; Tucker, Arthur O.; Dill, Norman H.
       1979. Rare and endangered vascular plants of Maryland. Newton Corner,
       MA: U.S. Fish and Wildlife Service. 64 p.  [16508]

 .  Clarke, J. H. 1960. Getting started with rhododendrons and azaleas. New
       York: Doubleday & Company, Inc.. 268 p.  [9649]

 .  Doran, William L. 1941. The propagation of some trees and shrubs by
       cuttings. Bulletin No. 382. Amherst, MA: Massachusetts State College,
       Massachusetts Agricultural Experiment Station. 56 p.  [20255]

 .  Eyre, F. H., ed. 1980. Forest cover types of the United States and
       Canada. Washington, DC: Society of American Foresters. 148 p.  [905]

 .  Garrison, George A.; Bjugstad, Ardell J.; Duncan, Don A.; [and others].
       1977. Vegetation and environmental features of forest and range
       ecosystems. Agric. Handb. 475. Washington, DC: U.S. Department of
       Agriculture, Forest Service. 68 p.  [998]

 .  Gleason, Henry A.; Cronquist, Arthur. 1991. Manual of vascular plants of
       northeastern United States and adjacent Canada. 2nd ed. New York: New
       York Botanical Garden. 910 p.  [20329]

 .  Horsley, Stephen B. 1988. How vegetation can influence regeneration. In:
       Smith, H. Clay; Perkey, Arlyn W.; Kidd, William E., Jr, eds. Guidelines
       for regenerating Appalachian hardwood stands: Workshop proceedings; 1988
       May 24-26; Morgantown, WV. Society of American Foresters Publ. 88-03.
       Morgantown, WV: West Virginia University Books: 38-54.  [13544]

.  Kuchler, A. W. 1964. Manual to accompany the map of potential vegetation
       of the conterminous United States. Special Publication No. 36. New York:
       American Geographical Society. 77 p.  [1384]

.  Libscomb, M. V.; Nilsen, E. T. 1990. Environmental and physiological
       factors influencing the natural distribution of evergreen and deciduous
       ericaceous shrubs on ne. and southwest facing slopes of the southern
       Appalachian Mountains. II. Water relations. American Journal of Botany.
       77(4): 517-526.  [11652]

.  Malik, A. A.; Blazich, F. A.; Warren, S. L.; Shelton, J. E. 1992.
       Initial growth of seedlings of flame azalea in response to day/night
       temperature. Journal of the American Society of Horticultural Science.
       117(2): 216-219.  [23050]

.  McCance, R. M., Jr.; Burns, J. F., eds. 1984. Ohio endangered and
       threatened vascular plants: Abstracts of state-listed taxa. Columbus,
       OH: Department of Natural Resources, Division of Natural Areas and
       Preserves. 635 p.  [22520]

.  McGinnies, William G. 1972. North America. In: McKell, Cyrus M.;
       Blaisdell, James P.; Goodin, Joe R., tech. eds. Wildland shrubs--their
       biology and utilization: An international symposium: Proceedings; 1971
       July; Logan, UT. Gen. Tech. Rep. INT-1. Ogden, UT: U.S. Department of
       Agriculture, Forest Service, Intermountain Forest and Range Experiment
       Station: 55-66.  [22750]

.  McNab, Henry W. 1988. Hardwoods and site quality. In: Smith, H. Clay;
       Perkey, Arlyn W.; Kidd, William E., Jr., eds. Guidelines for
       regenerating Appalachian hardwood stands: Workshop proceedings; 1988 May
       24-26; Morgantown, WV. SAF Publ. 88-03. Morgantown, WV: West Virginia
       University Books: 226-240.  [13949]

.  Olson, David F., Jr. 1974. Rhododendron L.  rhododendron. In:
       Schopmeyer, C. S., ed. Seeds of woody plants in the United States.
       Agric. Handb. 450. Washington, DC: U.S. Department of Agriculture,
       Forest Service: 709-712.  [7739]

.  Pellett, N.; Halvorsen, L. 1981. The search for hardy azaleas
       Rhododendron calendulaceum, Mt. Pisgah in North Carolina. American
       Nurseryman. 153(11): 7, 107.  [23051]

.  Pellett, N. E.; Rowan, N.; Aleong, J. 1991. Cold hardiness of various
       provenances of flame, roseshell, and swamp azaleas. Journal of the
       American Society of Horticultural Science. 116(1): 23-26.  [23052]

.  Quarterman, Elsie; Turner, Barbara Holman; Hemmerly, Thomas E. 1972.
       Analysis of virgin mixed mesophytic forests in Savage Gulf, Tennessee.
       Bulletin of the Torrey Botanical Club. 99(5): 228-232.  [11128]

.  Radford, Albert E.; Ahles, Harry E.; Bell, C. Ritchie. 1968. Manual of
       the vascular flora of the Carolinas. Chapel Hill, NC: The University of
       North Carolina Press. 1183 p.  [7606]

.  Raunkiaer, C. 1934. The life forms of plants and statistical plant
       geography. Oxford: Clarendon Press. 632 p.  [2843]

.  Read, D. J. 1983. The biology of mycorrhiza in the Ericales. Canadian
       Journal of Botany. 61: 985-1004.  [10602]

.  Sanders, C. R. 1978. Some aspects of the propagation of Rhododendron,
       Mahonia, and Ilex by cuttings. Combined Proceedings, International Plant
       Propagators Society. 28: 228-232.  [10693]

.  Stickney, Peter F. 1989. Seral origin of species originating in northern
       Rocky Mountain forests. Unpublished draft on file at: U.S. Department of
       Agriculture, Forest Service, Intermountain Research Station, Fire
       Sciences Laboratory, Missoula, MT; RWU 4403 files. 7 p.  [20090]

.  U.S. Department of Agriculture, Soil Conservation Service. 1982.
       National list of scientific plant names. Vol. 1. List of plant names.
       SCS-TP-159. Washington, DC. 416 p.  [11573]

.  Whittaker, R. H. 1956. Vegetation of the Great Smoky Mountains.
       Ecological Monographs. 26(1): 1-79.  [11108]

.  Wilhelm, Gene. 1973. Fire ecology in Shenandoah National Park. In:
       Komarek, Edwin V., Sr., technical coordinator. Proceedings, annual Tall
       Timbers fire ecology conference; 1972 June 8-9; Lubbock, TX. Number 12.
       Tallahassee, FL: Tall Timbers Research Station: 445-488.  [8477]

.  Willingham, F. F., Jr. 1976. Variation and phenological forms in
       Rhododendron calendulaceum (Michx.) Torrey (Ericaceae). Castanea. 41(3):
       215-223.  [23053]

.  Wofford, B. Eugene. 1989. Guide to the vascular plants of the Blue
       Ridge. Athens, GA: The University of Georgia Press. 384 p.  [12908]

.  Young, Stephen M., editor. 1992. New York state rare plant status list.
       August 1992. Latham, NY: Department of Environmental Conservation,
       Divisison of Lands and Forests, Natural Heritage Program. 79 p.  [22563]

Related categories for Species: Rhododendron calendulaceum | Flame Azalea