Ambrosia trifida

Distribution Map: Based on vouchered plant specimens from wild populations. Cultivated occurrences are not mapped. View county names by placing the cursor over the map.

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Family:	ASTERACEAE
Species:	Ambrosia trifida L.
Common Name:	GIANT RAGWEED
Status:	Native, FAC (NWPL)
Specimen:	View details of USF Herbarium specimens

** Not applicable or data not available.

Classification

Division
Class
Sub Class
Order	ASTERALES
Family	ASTERACEAE
Genus	Ambrosia
Species	Ambrosia trifida L. - GIANT RAGWEED

Citation

Citation	AMBROSIA TRIFIDA Linnaeus, Sp. Pl. 988. 1753.
Basionym:	**
Type:	Without data (lectotype: LINN 1114.1). Lectotypified by W. W. Payne, Trans. Wisconsin Acad. Sci. 58: 366. 1970.

** Not applicable or data not available.

Source

County	Herbaria	Literature Citation (If Applicable)
Broward	USF
Clay	USF
Escambia	FLAS
Franklin	FSU
Gadsden	FSU
Hamilton	FSU
Jackson	FSU
Jefferson	USF
Leon	FSU
Madison	FSU
Marion	FLAS
Taylor	FSU
Wakulla	FSU

Synonyms

– Denotes synonyms that are applicable to the state. Show these synonyms only

Synonym	Full Citation	Basionym	Type
Ambrosia trifida var. normalis	Ambrosia trifida Linnaeus, var. normalis Kuntze, Revis. Gen. Pl. 1: 305. 1891, nom. inadmiss.	BASIONYM: Ambrosia trifida Linnaeus 1753.
Ambrosia aptera	Ambrosia aptera de Candolle, Prodr. 5: 527. 1836.
Ambrosia integrifolia	Ambrosia integrifolia Muhlenberg ex Willdenow, Sp. Pl. 4: 375. 1803.		TYPE: PENNSYLVANIA: Without data, Muhlenberg 442 (holotype: B-W).
Ambrosia simplicifolia	Ambrosia simplicifolia Walter, Fl. Carol. 231. 1788.		TYPE: SOUTH CAROLINA:
Ambrosia striata	Ambrosia striata Rydberg, Brittonia 1: 96. 1931.		TYPE: COLORADO: Weld Co.: Windson, Aug 1901, Osterhout 2338 (holotype: NY).
Ambrosia trifida forma integrifolia	Ambrosia trifida Linnaeus, forma integrifolia (Muhlenberg ex Willdenow) Fernald, Rhodora 40: 347. 1938.	BASIONYM: Ambrosia integrifolia Muhlenberg ex Willdenow 1803.
Ambrosia trifida var. aptera	Ambrosia trifida Linnaeus, var. aptera (de Candolle) Kuntze, Revis. Gen. Pl. 1: 305. 1891.	BASIONYM: Ambrosia aptera de Candolle 1836.
Ambrosia trifida var. heterophylla	Ambrosia trifida Linnaeus, var. heterophylla Kuntze, Revis. Gen. Pl. 1: 305. 1891.		TYPE: OHIO: Hamilton Co.: Cincinnati,
Ambrosia trifida var. integrifolia	Ambrosia trifida Linnaeus, var. integrifolia (Muhlenberg ex Willdenow) Torrey & A. Gray, Fl. N. Amer. 2: 290. 1842.	BASIONYM: Ambrosia integrifolia Muhlenberg ex Willdenow 1803.
Ambrosia trifida var. polyploidea	Ambrosia trifida Linnaeus, var. polyploidea J. Rousseau, Naturaliste Canad. 71: 215. 1944.		TYPE: CANADA: Quebec: Near Montreal, cult. at Montreal, 23 Oct 1938, Morin et al. s.n. (holotype: MTJB).
Ambrosia trifida var. texana	Ambrosia trifida Linnaeus, var. texana Scheele, Linnaea 22: 156. 1849.		TYPE: TEXAS:
Ambrosia variabilis	Ambrosia variabilis Rydberg, Brittonia 1: 97. 1931.		TYPE: SOUTH DAKOTA: Lawrence Co.: Deadwood, 4 Aug 1913, Carr 124 (holotype: NY).

Specimens

Country	State	County	Date	Specimen
USA	Florida	Broward Co.	18 Jul 2007	P. L. Howell 1014
USA	Florida	Jefferson Co.	05 Oct 1991	R. Mears s.n.
USA	Florida	Clay Co.	01 Aug 1970	D. W. Hall s.n.
USA	Louisiana	Lincoln Par.	27 Sep 1978	E. Withers 1100
USA	Louisiana	Lincoln Par.	14 Sep 1972	C. W. Sibley 21
USA	Louisiana	Lincoln Par.	18 Sep 1970	R. Linder 545
USA	Alabama	Jackson Co.	29 Sep 2001	K. Francl 208
USA	North Carolina	Ashe Co.	01 Aug 1958	A. E. Radford 38464
USA	Louisiana	Lincoln Par.	14 Sep 1972	J. C. Dean 29
USA	Louisiana	Plaquemines Par.	16 Sep 1991	M. Garrison 168
USA	North Carolina	Polk Co.	18 Aug 1975	C. L. Rodgers 75411
USA	Louisiana	Rapides Par.	03 Oct 1967	R. D. Thomas 5325

Listed Status: Florida

Listed Status:	(Florida):Source - Plants in the Preservation of Native Flora of Florida Act. Chapter 5B-40, Florida Administrative Code. 1998, amended.
Endangered:	A species of plants native to the state that are in imminent danger of extinction within the state, the survival of which is unlikely if the causes of a decline in the number of plants continue, and includes all species determined to be endangered or threatened pursuant to the Federal Endangered Species Act of 1973, as amended.
Threatened:	Listed as Threatened Plants in the Preservation of Native Flora of Florida Act. Defined as species of plants native to the state that are in rapid decline in the number of plants within the state, but which have not so decreased in such number as to cause them to be endangered.

Listed Status: US

Listed Status: US	(U.S.) Source - List of Endangered and Threatened Wildlife and Plants under the provisions of the Endangered Species Act of 1973, as amended.
Endangered:	Any species which is in danger of extinction throughout all or a significant portion of its range.
Threatened:	Any species which is likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range.

WAP: Wetland AssessmentProcedure

Wetland Assessment Procedure (WAP): Source - Southwest Florida Water Management District, Wetland Assessment Procedure Instruction Manual for Isolated Wetlands (March 2005).

AD:	Adaptive Species. Plant species designated as FAC or Upland by DEP, but commonly seen in the transition zone in limited numbers.
D:	Deep Species. Plant species commonly found in the deep zone, and designated either FAC or OBL by DEP.
OD:	Outer Deep Species. Plant species commonly found in the outer deep zone, and designated either FACW or OBL by DEP.
T:	Transition Species. Plant species commonly found in the transition zone, and designated either FACW or OBL by DEP.
U:	Upland Species. Plant species that are not expected to be seen in wetlands.

ANY - WAP critieria is not taken into consideration
Yes - Show results with WAP designations
No - Show results without WAP designations

FISC: Florida Invasive Species Council

FISC:

Source - Florida Invasive Species Council's 2017 List of Florida's Most Invasive Species

Category I - Species that are invading and disrupting native plant communities in Florida. This definition does not rely on the economic severity or geographic range of the problem, but on the documented ecological damage caused.

Category II - Species that have shown a potential to disrupt native plant communities. These species may become ranked as Category I, but have not yet demonstrated disruption of natural Florida communities.

DEP: Department of Environmental Protection

Wetland Status, Department of Environmental Regulation (DEP): Source - Delineation of the Landward Extent of Wetlands and Surface Waters, Chapter 62-340, Florida Administrative Code. 1994.

OBL:	Obligate wetland. Occurs almost always under natural conditions in wetlands.
FACW:	Facultative Wetland. Usually occurs in wetlands, but occasionally found in non-wetlands
FAC:	Facultative. equally likely to occur in wetlands or non-wetlands.

NWPL: National Wetland Plant List

National Wetland Plant List (NWPL): Source - Lichvar, R.W., M. Butterwick, N.C. Melvin, and W.N. Kirchner. 2014. The National Wetland Plant List: 2014 Update of Wetland Ratings. Phytoneuron 2014-41: 1-42.

OBL:	Obligate Wetland. Occurs almost always (estimated probability 99%) under natural conditions in wetlands.
FACW:	Facultative Wetland. Usually occurs in wetlands (estimated probability 67%-99%), but occasionally found in non-wetlands.
FAC:	Facultative. Equally likely to occur in wetlands or non-wetlands (estimated probability 34%-66%).
FACU:	Facultative Upland. Usually occurs in non-wetlands (estimated probability 67%-99%), but occasionally found in wetlands (estimated probability 1%-33%).
UPL:	Obligate Upland. Occurs in wetlands in another region, but occurs almost always (estimated probability 99%) under natural conditions in non-wetlands in the regions specified.

Persisting

Identifying species that appear as waifs or only periodically appear in the flora for a few seasons.

Any - Persisting critieria is not taken into consideration
Yes - Show results with a Persisting value of Y
No - Show results without Persisting value of N

Duration

Annual:	Plants that perform their entire lifecycle within a single growing season. All roots, stems, and leaves die at the end of the growing season. Over wintering seeds allow the next generation to appear.
Biennial:	A plant that is typically vegetative its first year and blooms the following season. Once it has bloomed and set seed, the plant dies. Garlic mustard is an example of a biennial.
Perennial:	These plants live for three or more seasons. Many perennials may not be mature enough to bloom during its first year. Perennial wildflowers re-grow each season from overwinter root material.

Category

Vascular:	Any of various plants that have the vascular tissues xylem and phloem. The vascular plants include all seed-bearing plants (the gymnosperms and angiosperms) and the pteridophytes (including the ferns, lycophytes, and horsetails). Also called tracheophyte.
Bryophyte:	A large group of seedless green plants including the mosses, liverworts, and hornworts. Bryophytes lack the specialized tissues xylem and phloem that circulate water and dissolved nutrients in the vascular plants. Bryophytes generally live on land but are mostly found in moist environments, for they have free-swimming sperm that require water for transport. In contrast to the vascular plants, the gametophyte (haploid) generation of bryophytes constitutes the larger plant form, while the small sporophyte (diploid) generation grows on or within the gametophyte and depends upon it for nutrition.
Lichen:	The mutualistic symbiotic association of a fungus with an alga or a cyanobacterium, or both. The fungal component of a lichen absorbs water and nutrients from the surroundings and provides a suitable environment for the alga or cyanobacterium. These live protected among the dense fungal hyphae and produce carbohydrates for the fungus by photosynthesis. Owing to this partnership, lichens can thrive in harsh environments such as mountaintops and polar regions. The more familiar lichens grow slowly as crusty patches, but lichens are found in a variety of forms, such as the tall, plantlike reindeer moss. The association between the different organisms in a lichen is so close that lichens are routinely referred to as a single organism, and scientists classify lichens using the name of the fungal component.

(Definitions from: American Heritage Science Dictionary)

Growth Habit

Intro paragraph to be provided by New York.

Vine:	DESCRIPTION TO BE PROVIDED BY NEW YORK.
Shrub:	DESCRIPTION TO BE PROVIDED BY NEW YORK.
Tree:	DESCRIPTION TO BE PROVIDED BY NEW YORK.
Et cetera:	DESCRIPTION TO BE PROVIDED BY NEW YORK.

State Rank

This numeric rank provides the relative rarity for each species based on a scale from 1 (very rare) to 5 (common). These ranks carry no legal status.

S1 - Typically 5 or fewer occurrences, very few remaining individuals, acres, or miles of stream, or some factor of its biology making it especially vulnerable in the state.
S2 - Typically 6 to 20 occurrences, few remaining individuals, acres, or miles of stream, or factors demonstrably making it very vulnerable in the state.
S3 - Typically 21 to 100 occurrences, limited acreage, or miles of stream in the state.
S4 - Apparently secure in the state.
S5 - Demonstrably secure in the state.
SE - State exotic or non-native.
SH - Historically known from the state, but not seen in the past 15 years.
SNA - Species for which a rank is not applicable. This is mainly those species which are now excluded from flora for various reasons.
SNR - Not yet ranked.
SX - Apparently extirpated from the state.

Global Rank

Each species' global rank is determined by NatureServe. These ranks carry no legal weight. The global rank reflects the species worldwide rarity.

G1 - Critically imperiled globally because of extreme rarity (5 or fewer occurrences), or very few remaining acres, or miles of stream) or especially vulnerable to extinction because of some factor of its biology.
G2 - Imperiled globally because of rarity (6 - 20 occurrences, or few remaining acres, or miles of stream) or very vulnerable to extinction throughout its range because of other factors.
G3 - Imperiled globally because of rarity (6 - 20 occurrences, or few remaining acres, or miles of stream) or very vulnerable to extinction throughout its range because of other factors.
G4 - Imperiled globally because of rarity (6 - 20 occurrences, or few remaining acres, or miles of stream) or very vulnerable to extinction throughout its range because of other factors.
G5 - Demonstrably secure globally, though it may be quite rare in parts of its range, especially at the periphery.
GH - Historically known, with the expectation that it might be rediscovered.
GNA - Species for which a rank is not applicable. NatureServe does not typically rank hybrid species.
GNR - Not yet ranked.
GX - Species believed to be extinct.

Filter by County - Counties to Include - ANY versus ALL

Any - An Any search will combine the list of counties to include with a Boolean Or. Plant species returned will be found within at least one of the selected counties.
All - An All search will combine the list of counties to include with a Boolean And. Plant species returned will be found within each of the selected counties.

Filter by County - Counties to Exclude - ANY versus ALL

Any - An Any search will combine the list of counties to exclude with a Boolean Or. Plant species returned will not be found within at least one of the selected counties.
All - An All search will combine the list of counties to exclude with a Boolean And. Plant species returned will not be found within any of the selected counties.

Associated Ecological Communities

View a List of All Ecological Communities

For more information, contact: Richard Wunderlin or Bruce Hansen, Alan Franck, or Karla Alvarado

Web Development: USF Water Institute

A member of the University of South Florida family of PlantAtlas.org websites

Citation Information:

Wunderlin, R. P., B. F. Hansen, A. R. Franck, and F. B. Essig. 2024. Atlas of Florida Plants (http://florida.plantatlas.usf.edu/). [S. M. Landry and K. N. Campbell (application development), USF Water Institute.] Institute for Systematic Botany, University of South Florida, Tampa.

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Definition: Vouchered Specimen

A voucher specimen is a pressed and thoroughly dried plant sample deposited in a herbarium, and is intended to be a permanent record supporting research purposes. A voucher may be a record of a plant's occurrence in a particular area, or a specific example of a plant used in a scientific investigation.

Proper vouchers display all the necessary attributes for complete identification of the plant, and are to be accompanied by accurate locality, habitat, collection time, and collector data.

Only plant populations vouchered by specimens deposited in Index Herbariorum http://sweetgum.nybg.org/science/ih/ recognized herbaria are represented on this map.