Overview

Comprehensive Description

Comments

This huge plant is probably an allergy sufferer's worst nightmare. It has some ecological value to various moths, but otherwise is less important than Ambrosia artemesiifolia (Common Ragweed). Giant Ragweed can be distinguished from other Ambrosia spp. (Ragweeds) by its palmately lobed leaves; other Ragweeds have leaves that are pinnatifid or bipinnatifid. The name of this genus of plants refers to ambrosia, "the food of the gods" in antiquity. This seems like a strange name for a group of unattractive plants, unless it refers to the value of the seeds of certain species from a bird's point of view. Return
Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© John Hilty

Source: Illinois Wildflowers

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Description

This is a native annual plant from 3-12' tall, branching occasionally. The green stems are covered with white hairs. The opposite leaves are up to 12" long and 8" across. The larger leaves are divided into 3 or 5 lobes, usually serrated along the margins, and have long petioles that are sometimes winged. The smaller leaves near the base of an inflorescence are lanceolate and often hairy underneath. Many of the upper stems terminate in a cylindrical spike of flowers, about 3-6" long, with one or more smaller spikes near its base. The small flowers are are yellowish green and devoid of petals and sepals. They occur in small drooping clusters less than ¼" across on short pedicels, and are densely arranged all around each spike. The fine pollen of the male flowers is easily carried aloft by the wind. This typically occurs during late summer or early fall. The seeds are large, tough-coated, and remain viable in the soil for several years. The root system is fibrous. Cultivation
Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© John Hilty

Source: Illinois Wildflowers

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Distribution

Range and Habitat in Illinois

Giant Ragweed is a common plant that occurs in every county of Illinois (see Distribution Map). It can be found in disturbed areas of moist to mesic black soil prairies, especially along the margins near woodlands or fields. Other native habitats include disturbed areas of moist clay prairies, meadows in woodland areas or near rivers, thickets, and woodland borders. In more developed areas, it occurs in vacant lots, cropland, abandoned fields, poorly drained waste areas, areas along roadsides and railroads, and fence rows. Faunal Associations
Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© John Hilty

Source: Illinois Wildflowers

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

National Distribution

United States

Origin: Unknown/Undetermined

Regularity: Regularly occurring

Currently: Unknown/Undetermined

Confidence: Confident

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

National Distribution

Canada

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Physical Description

Morphology

Description

Annuals, 30–150(–400+) cm. Stems erect. Leaves mostly opposite; petioles 10–30(–70+) mm; blades rounded-deltate to ovate or elliptic, 40–150(–250+) × 30–70(–200+) mm, usually some blades palmately 3(–5)-lobed, bases truncate to cuneate (sometimes decurrent onto petioles), margins usually toothed, rarely entire, abaxial and adaxial faces ± scabrellous and gland-dotted. Pistillate heads clustered, proximal to staminates; florets 1. Staminate heads: peduncles 1–3+ mm; involucres ± saucer-shaped, 2–4 mm diam., scabrellous (often with 1–3 black nerves); florets 3–25+. Burs: bodies ± pyramidal, 3–5(–7+) mm, glabrous or glabrate, spines 4–5, ± distal, ± acerose, 0.5–1 mm, tips straight (bases ± decurrent as ribs). 2n = 24, 48.
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Missouri Botanical Garden, 4344 Shaw Boulevard, St. Louis, MO, 63110 USA

Source: Missouri Botanical Garden

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Diagnostic Description

Synonym

Ambrosia aptera de Candolle; A. trifida var. integrifolia (Muhlenberg ex Willdenow) Torrey & A. Gray; A. trifida var. texana Scheele
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Missouri Botanical Garden, 4344 Shaw Boulevard, St. Louis, MO, 63110 USA

Source: Missouri Botanical Garden

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Type Information

Isotype for Ambrosia trifida var. texana Scheele
Catalog Number: US 1814933
Collection: Smithsonian Institution, National Museum of Natural History, Department of Botany
Preparation: Pressed specimen
Collector(s): F. J. Lindheimer
Year Collected: 1846
Locality: Texas, United States, North America
  • Isotype: Scheele, G. H. A. 1849. Linnaea. 22: 156.
Creative Commons Attribution 3.0 (CC BY 3.0)

© Smithsonian Institution, National Museum of Natural History, Department of Botany

Source: National Museum of Natural History Collections

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Ecology

Habitat

Range and Habitat in Illinois

Giant Ragweed is a common plant that occurs in every county of Illinois (see Distribution Map). It can be found in disturbed areas of moist to mesic black soil prairies, especially along the margins near woodlands or fields. Other native habitats include disturbed areas of moist clay prairies, meadows in woodland areas or near rivers, thickets, and woodland borders. In more developed areas, it occurs in vacant lots, cropland, abandoned fields, poorly drained waste areas, areas along roadsides and railroads, and fence rows. Faunal Associations
Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© John Hilty

Source: Illinois Wildflowers

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Associations

Flower-Visiting Insects of Giant Ragweed in Illinois

Ambrosia trifida (Giant Ragweed)
(Wind-pollinated; honeybees collect pollen, while the wasp merely explores the flowers; observations are from Robertson)

Bees (short-tongued)
Apidae (Apinae): Apis mellifera cp fq

Wasps
Vespidae: Vespula germanica exp

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Molecular Biology and Genetics

Molecular Biology

Barcode data: Ambrosia trifida

The following is a representative barcode sequence, the centroid of all available sequences for this species.


Creative Commons Attribution 3.0 (CC BY 3.0)

© Barcode of Life Data Systems

Source: Barcode of Life Data Systems (BOLD)

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Statistics of barcoding coverage: Ambrosia trifida L.

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 0
Specimens with Barcodes: 2
Species With Barcodes: 1
Creative Commons Attribution 3.0 (CC BY 3.0)

© Barcode of Life Data Systems

Source: Barcode of Life Data Systems (BOLD)

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Statistics of barcoding coverage: Ambrosia trifida

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 5
Specimens with Barcodes: 13
Species With Barcodes: 1
Creative Commons Attribution 3.0 (CC BY 3.0)

© Barcode of Life Data Systems

Source: Barcode of Life Data Systems (BOLD)

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Conservation

Conservation Status

National NatureServe Conservation Status

United States

Rounded National Status Rank: NNR - Unranked

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

NatureServe Conservation Status

Rounded Global Status Rank: T5 - Secure

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

National NatureServe Conservation Status

Canada

Rounded National Status Rank: N5 - Secure

United States

Rounded National Status Rank: N5 - Secure

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

NatureServe Conservation Status

Rounded Global Status Rank: G5 - Secure

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Wikipedia

Ambrosia trifida

Ambrosia trifida is a species of flowering plant in the aster family, Asteraceae. It is native to North America, where it is widespread in Canada, the United States, and northern Mexico. It is present in Europe and Asia as an introduced species, and it is known as a common weed in many regions.[2] Its common names include great ragweed, Texan great ragweed, giant ragweed, tall ragweed, blood ragweed, perennial ragweed, horseweed,[3] buffaloweed, and kinghead.[4]

Description[edit]

This is an annual herb usually growing up to 2 meters tall, but known to reach 6 meters in rich, moist soils. The tough stems have woody bases and are branching or unbranched.[4] Most leaves are oppositely arranged. The blades are variable in shape, sometimes palmate with five lobes, and often with toothed edges. The largest can be over 25 centimeters long by 20 wide. They are borne on petioles several centimeters long. They are glandular and rough in texture. The species is monoecious, with plants bearing inflorescences containing both pistillate and staminate flowers. The former are clustered at the base of the spike and the latter grow at the end. The fruit is a bur a few millimeters long tipped with several tiny spines.[1][5]

As a weed[edit]

This species is well known as a noxious weed, both in its native range and in areas where it is an introduced and often invasive species. It is naturalized in some areas, and it is recorded as an adventive species in others.[2] It grows in many types of disturbed habitat, such as roadsides, and in cultivated fields. Widespread seed dispersal occurs when its spiny burs fall off the plant and are carried to new habitat by people, animals, machinery, or flowing water. The plant is destructive to native and crop plants because it easily outcompetes them for light.[4]

As an allergen[edit]

There is also great interest in preventing the spread of this plant because its pollen is a significant human allergen.[6] It is one of the most familiar allergenic ragweeds, and residents of different regions begin to experience allergic symptoms as the plant spreads into the area.[7]

Uses[edit]

Native Americans had a number of uses for the plant as traditional medicine. The Cherokee used it as a remedy for insect stings, hives, fever, and pneumonia, and the Iroquois used it to treat diarrhea.[8]

Giant ragweed has been used successfully as a compost activator and an ingredient in sheet mulch gardens.[9]

Gallery[edit]

References[edit]

  1. ^ a b Ambrosia trifida. Flora of North America.
  2. ^ a b Ambrosia trifida. Germplasm Resources Information Network (GRIN).
  3. ^ Ambrosia trifida. Integrated Taxonomic Information System (ITIS).
  4. ^ a b c Ambrosia spp. Encycloweedia. California Department of Food and Agriculture.
  5. ^ Ambrosia trifida. The Jepson eFlora 2013.
  6. ^ Ghosh, B., et al. (1991). Cloning the cDNA encoding the AmbtV allergen from giant ragweed (Ambrosia trifida) pollen. Gene 101(2), 231-38.
  7. ^ Makra, L., et al. (2005). The history and impacts of airborne Ambrosia (Asteraceae) pollen in Hungary. Grana 44(1), 57-64.
  8. ^ Ambrosia trifida. Native American Ethnobotany. University of Michigan, Dearborn.
  9. ^ Stallings, Ben. "Ragweed: Curse or Blessing, the Choice is Yours". Permaculture News. Permaculture Research Institute. Retrieved 27 June 2014. 
Creative Commons Attribution Share Alike 3.0 (CC BY-SA 3.0)

Source: Wikipedia

Unreviewed

Article rating from 0 people

Default rating: 2.5 of 5

Notes

Comments

The name Ambrosia ×helenae Rouleau applies to hybrids between A. artemisiifolia and A. trifida. Hybrids between A. bidentata and A. trifida have been recorded. Ambrosia trifida may be no longer extant in British Columbia.
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Missouri Botanical Garden, 4344 Shaw Boulevard, St. Louis, MO, 63110 USA

Source: Missouri Botanical Garden

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Disclaimer

EOL content is automatically assembled from many different content providers. As a result, from time to time you may find pages on EOL that are confusing.

To request an improvement, please leave a comment on the page. Thank you!