Difference between revisions of "Vernonia angustifolia"

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Common name: Tall ironweed
 
Common name: Tall ironweed
 
==Taxonomic notes==
 
==Taxonomic notes==
Variety: ''Vernonia angustifolia'' Michaux var. ''angustifolia''; ''Vernonia angustifolia'' Michaux var. ''mohrii'' S.B. Jones; ''Vernonia angustifolia'' Michaux var. ''scaberrima'' (Nuttall) A. Gray.<ref>Weakley, A.S. 2015. Flora of the southern and mid-atlantic states. Working Draf of 21 May 2015. University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.</ref>
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Varieties: ''Vernonia angustifolia'' Michaux var. ''angustifolia''; ''Vernonia angustifolia'' Michaux var. ''mohrii'' S.B. Jones; ''Vernonia angustifolia'' Michaux var. ''scaberrima'' (Nuttall) A. Gray.<ref>Weakley, A.S. 2015. Flora of the southern and mid-atlantic states. Working Draf of 21 May 2015. University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.</ref>
  
 
==Description==  
 
==Description==  
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==Distribution==
 
==Distribution==
 +
Ironweed is found throughout the southeastern coastal plains region from North Carolina to Florida to Mississippi.<ref>Denhof, Carol. 2013. Understory Plant Spotlight Tall Ironweed Vernonia angustifolia Michx. The Longleaf Leader. Vol. VI. Iss. 4. Page 9</ref>
 +
 
==Ecology==
 
==Ecology==
 
===Habitat=== <!--Natural communities, human disturbed habitats, topography, hydrology, soils, light, fire regime requirements for removal of competition, etc.-->
 
===Habitat=== <!--Natural communities, human disturbed habitats, topography, hydrology, soils, light, fire regime requirements for removal of competition, etc.-->
In the Coastal Plain region, ''V. angustifolia'' can be found in sand pine scrubs, longleaf pine-wiregrass flatwoods, edges of meadows, pine-turkey oak flats, longleaf pine savannas, mixed woodlands adjacent to floodplains, annually burned pinelands, longleaf pine-sedge-andropogon savannas, slash pine-wiregrass flats, oak scrubs, second growth hardwoods, cabbage palm hammocks, annually burned upland pines <ref name=birk> Birkhead, R. D., C. Guyer, et al. (2005). "Patterns of folivory and seed ingestion by gopher tortoises (Gopherus polyphemus) in a southeastern pine savanna." American Midland Naturalist 154: 143-151. </ref> <ref name=fsu> Florida State University Robert K. Godfrey Herbarium database. URL: http://herbarium.bio.fsu.edu. Last accessed: July 2015. Collectors: Loran C. Anderson, Robert K. Godfrey, Nancy E. Jordan, R. Kral, K. Craddock Burks, Andre F. Clewell, P. L. Redfearn, Samuel B. Jones, Richard S. Mitchell, John C. Ogden, H. E. Grelen, James D. Ray, Jr., Gwynn W. Ramsey, E. S. Ford, C. Jackson, Robert L. Lazor, John D. Lazor, Gary R. Knight, Rodie White, R. A. Norris, R. Komarek, M. Davis, MacClendons, G. Wilder, Cecil R Slaughter. States and Counties: Florida: Bay, Calhoun, Citrus, Columbia, Duval, Escambia, Flagler, Franklin, Gadsden, Hernando, Highlands, Jackson, Lake, Leon, Liberty, Martin, Nassau, Okaloosa, Santa Rosa, Seminole, Suwannee, Taylor, Wakulla, Washington. Georgia: Baker, Coffee, Grady, Thomas. Compiled by Tall Timbers Research Station and Land Conservancy. </ref> and sandhill communities. <ref name=heu> Heuberger, K. A. and F. E. Putz (2003). "Fire in the suburbs: ecological impacts of prescribed fire in small remnants of longleaf pine (Pinus palustris) sandhill." Restoration Ecology 11: 72-81. </ref> It can also be found along roadsides, power line corridors, bulldozed pine-oak scrubs, and clobbered slash pine forests. Soil types include sandy loam, loose sand, loamy sands, sandy peat<ref name=fsu/>, and Utisols <ref name=coff> Coffey, K. L. and L. K. Kirkman (2006). "Seed germination strategies of species with restoration potential in a fire-maintained pine savanna." Natural Areas Journal 26: 289-299. </ref> Associated species include ''Aristida, Serenoa repens, Ilex glabra, Liatris, Andropogon, Panicum'', and ''Leptoloma cognata''. <ref name=fsu/>
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In the Coastal Plain region, ''V. angustifolia'' can be found in sand pine scrubs, longleaf pine-wiregrass flatwoods, edges of meadows, pine-turkey oak flats, longleaf pine savannas, mixed woodlands adjacent to floodplains, annually burned pinelands, longleaf pine-sedge-andropogon savannas, slash pine-wiregrass flats, oak scrubs, second growth hardwoods, cabbage palm hammocks, annually burned upland pines<ref name=birk> Birkhead, R. D., C. Guyer, et al. (2005). "Patterns of folivory and seed ingestion by gopher tortoises (Gopherus polyphemus) in a southeastern pine savanna." American Midland Naturalist 154: 143-151.</ref><ref name=fsu> Florida State University Robert K. Godfrey Herbarium database. URL: http://herbarium.bio.fsu.edu. Last accessed: July 2015. Collectors: Loran C. Anderson, Robert K. Godfrey, Nancy E. Jordan, R. Kral, K. Craddock Burks, Andre F. Clewell, P. L. Redfearn, Samuel B. Jones, Richard S. Mitchell, John C. Ogden, H. E. Grelen, James D. Ray, Jr., Gwynn W. Ramsey, E. S. Ford, C. Jackson, Robert L. Lazor, John D. Lazor, Gary R. Knight, Rodie White, R. A. Norris, R. Komarek, M. Davis, MacClendons, G. Wilder, Cecil R Slaughter. States and Counties: Florida: Bay, Calhoun, Citrus, Columbia, Duval, Escambia, Flagler, Franklin, Gadsden, Hernando, Highlands, Jackson, Lake, Leon, Liberty, Martin, Nassau, Okaloosa, Santa Rosa, Seminole, Suwannee, Taylor, Wakulla, Washington. Georgia: Baker, Coffee, Grady, Thomas. Compiled by Tall Timbers Research Station and Land Conservancy.</ref> and sandhill communities.<ref name=heu> Heuberger, K. A. and F. E. Putz (2003). "Fire in the suburbs: ecological impacts of prescribed fire in small remnants of longleaf pine (Pinus palustris) sandhill." Restoration Ecology 11: 72-81.</ref> A study exploring longleaf pine patch dynamics found ''V. angustifolia'' to be most strongly represented within stands of longleaf pine that are between 90-180 years of age.<ref>Mugnani et al. (2019).  “Longleaf Pine Patch Dynamics Influence Ground-Layer Vegetation in Old-Growth Pine Savanna”.</ref> This species can also be found along roadsides, power line corridors, bulldozed pine-oak scrubs, and clobbered slash pine forests. Soil types include sandy loam, loose sand, loamy sands, sandy peat<ref name=fsu/>, and Utisols<ref name=coff> Coffey, K. L. and L. K. Kirkman (2006). "Seed germination strategies of species with restoration potential in a fire-maintained pine savanna." Natural Areas Journal 26: 289-299.</ref> ''V. angustifolia'' is frequent and abundant in the North Florida Subxeric Sandhills community type and is an indicator species for the Clayhill Longleaf Woodlands community type as described in Carr et al. (2010).<ref>Carr, S.C., K.M. Robertson, and R.K. Peet. 2010. A vegetation classification of fire-dependent pinelands of Florida. Castanea 75:153-189.</ref>
  
''V. angustifolia'' responds negatively to agriculture-based soil disturbance in South Carolina's historically longleaf communities.<ref>Brudvig, L.A. and E.I. Damchen. (2011). Land-use history, historical connectivity, and land management interact to determine longleaf pine woodland understory richness and composition. Ecography 34: 257-266.</ref> This could also mark it as a possible indicator species for remnant woodland.<ref>Brudvig, L.A., E Grman, C.W. Habeck, and J.A. Ledvina. (2013). Strong legacy of agricultural land use on soils and understory plant communities in longleaf pine woodlands. Forest Ecology and Management 310: 944-955.</ref> When exposed to soil disturbance by military training in West Georgia, ''V. angustifolia'' responds negatively by way of absence.<ref>Dale, V.H., S.C. Beyeler, and B. Jackson. (2002). Understory vegetation indicators of anthropogenic disturbance in longleaf pine forests at Fort Benning, Georgia, USA. Ecological Indicators 1(3):155-170.</ref> It also responds negatively to soil disturbance by agriculture in Southwest Georgia.<ref>Kirkman, L.K., K.L. Coffey, R.J. Mitchell, and E.B. Moser. Ground Cover Recovery Patterns and Life-History Traits: Implications for Restoration Obstacles and Opportunities in a Species-Rich Savanna. (2004). Journal of Ecology 92(3):409-421.</ref>
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''V. angustifolia'' reduced its occurrence in response to agriculture-based soil disturbance in South Carolina's historically longleaf communities.<ref name=brudvig11>Brudvig, L.A. and E.I. Damchen. (2011). Land-use history, historical connectivity, and land management interact to determine longleaf pine woodland understory richness and composition. Ecography 34: 257-266.</ref> It has shown resistance to regrowth in reestablished pinelands that were disturbed by agricultural practices, making it a possible indicator species for remnant woodlands.<ref name=brudvig13>Brudvig, L.A., E Grman, C.W. Habeck, and J.A. Ledvina. (2013). Strong legacy of agricultural land use on soils and understory plant communities in longleaf pine woodlands. Forest Ecology and Management 310: 944-955.</ref> ''V. angustifolia'' became absent in response to military training in west Georgia pinelands.<ref name=dale>Dale, V.H., S.C. Beyeler, and B. Jackson. (2002). Understory vegetation indicators of anthropogenic disturbance in longleaf pine forests at Fort Benning, Georgia, USA. Ecological Indicators 1(3):155-170.</ref> It also decreased its occurrence in response to soil disturbance by agriculture in southwest Georgia.<ref name=kirkman>Kirkman, L.K., K.L. Coffey, R.J. Mitchell, and E.B. Moser. Ground Cover Recovery Patterns and Life-History Traits: Implications for Restoration Obstacles and Opportunities in a Species-Rich Savanna. (2004). Journal of Ecology 92(3):409-421.</ref>
  
''Vernonia angustifolia'' is frequent and abundant in the North Florida Subxeric Sandhills community type and is an indicator species for the Clayhill Longleaf Woodlands community type as described in Carr et al. (2010).<ref>Carr, S.C., K.M. Robertson, and R.K. Peet. 2010. A vegetation classification of fire-dependent pinelands of Florida. Castanea 75:153-189.</ref>
+
Associated species include ''Aristida, [[Serenoa repens]], [[Ilex glabra]], Liatris, Andropogon, Panicum'', and ''Leptoloma cognata''.<ref name=fsu/>
  
 
===Phenology=== <!--Timing off flowering, fruiting, seed dispersal, and environmental triggers.  Cite PanFlora website if appropriate: http://www.gilnelson.com/PanFlora/ -->
 
===Phenology=== <!--Timing off flowering, fruiting, seed dispersal, and environmental triggers.  Cite PanFlora website if appropriate: http://www.gilnelson.com/PanFlora/ -->
''V. angustifolia'' is a fall forb. <ref name=kirk> Kirkman, L. K., K. L. Coffey, et al. (2004). "Ground cover recovery patterns and life-history traits: implications for restoration obstacles and opportunities in a species-rich savanna." Journal of Ecology 92: 409-421.</ref> Showy-flowered sandhill species. <ref name=heu/> It has been observed flowering in January and June through October and fruits June through October.<ref name=fsu/><ref>Nelson, G.  [http://www.gilnelson.com/ PanFlora]: Plant data for the eastern United States with emphasis on the Southeastern Coastal Plains, Florida, and the Florida Panhandle. www.gilnelson.com/PanFlora/  Accessed: 15 DEC 2016</ref>
+
''V. angustifolia'' is a fall forb.<ref name=kirk> Kirkman, L. K., K. L. Coffey, et al. (2004). "Ground cover recovery patterns and life-history traits: implications for restoration obstacles and opportunities in a species-rich savanna." Journal of Ecology 92: 409-421.</ref> Showy-flowered sandhill species.<ref name=heu/> It has been observed flowering in January and June through October and fruits June through October.<ref name=fsu/><ref>Nelson, G.  [http://www.gilnelson.com/ PanFlora]: Plant data for the eastern United States with emphasis on the Southeastern Coastal Plains, Florida, and the Florida Panhandle. www.gilnelson.com/PanFlora/  Accessed: 15 DEC 2016</ref>
  
 
===Seed dispersal===
 
===Seed dispersal===
This species is thought to be dispersed by wind. <ref>Kirkman, L. Katherine. Unpublished database of seed dispersal mode of plants found in Coastal Plain longleaf pine-grasslands of the Jones Ecological Research Center, Georgia.</ref>
+
This species is thought to be dispersed by wind.<ref>Kirkman, L. Katherine. Unpublished database of seed dispersal mode of plants found in Coastal Plain longleaf pine-grasslands of the Jones Ecological Research Center, Georgia.</ref>
  
 
===Seed bank and germination===
 
===Seed bank and germination===
Less than 1% of ''V. angustifolia'' seeds remained viable after two years of burial. <ref name=coff/> So ''V. angustifolia'' does not have a short-term persistent soil seed bank and has little seed dormancy. <ref name=coff/>
+
Less than 1% of ''V. angustifolia'' seeds remained viable after two years of burial.<ref name=coff/> So ''V. angustifolia'' does not have a short-term persistent soil seed bank and has little seed dormancy.<ref name=coff/>
  
 
===Fire ecology=== <!--Fire tolerance, fire dependence, adaptive fire responses-->
 
===Fire ecology=== <!--Fire tolerance, fire dependence, adaptive fire responses-->
It can live in areas frequently burned. <ref name=coff/>
+
''Vernonia angustifolia'' can live in areas frequently burned<ref name=coff/> as shown in populations on the Pebble Hill plantation of north Florida and Wade Tract of south Georgia that have been known to persist through repeated annual burns.<ref>Robertson, K.M. Unpublished data collected from Pebble Hill Fire Plots, Pebble Hill Plantation, Thomasville, Georgia.</ref><ref>Platt, W.J., R. Carter, G. Nelson, W. Baker, S. Hermann, J. Kane, L. Anderson, M. Smith, K. Robertson. 2021. Unpublished species list of Wade Tract old-growth longleaf pine savanna, Thomasville, Georgia.</ref>
<!--===Pollination===-->  
 
  
===Use by animals=== <!--Herbivory, granivory, insect hosting, etc.-->
+
<!--===Pollination===-->
In Southeastern pine savannas, ''V. angustifolia'' was found in 6.25% of the active gopher tortoise (''Gopherus polyphemus'') burrows.<ref name=birk/>
+
===Herbivory and toxicology=== <!--Common herbivores, granivory, insect hosting, poisonous chemicals, allelopathy, etc.-->
 +
''Vernonia angustifolia'' has been observed with leafcutting bees such as ''Megachile mendica'' (family Megachilidae).<ref>Discoverlife.org [https://www.discoverlife.org/20/q?search=Bidens+albaDiscoverlife.org|Discoverlife.org]</ref> In Southeastern pine savannas, ''V. angustifolia'' was found in 6.25% of the active gopher tortoise (''Gopherus polyphemus'') burrows<ref name=birk/> and is a nectar plant for native pollinators.<ref>Denhof, Carol. 2013. Understory Plant Spotlight Tall Ironweed Vernonia angustifolia Michx. The Longleaf Leader. Vol. VI. Iss. 4. Page 9</ref>
 
<!--===Diseases and parasites===-->
 
<!--===Diseases and parasites===-->
==Conservation and management==
+
 
==Cultivation and restoration==
+
==Conservation, cultivation, and restoration==
 +
''V. angustifolia'' should avoid soil disturbance by military training and agriculture to conserve its presence in pine communities.<ref name=brudvig11/><ref name=brudvig13/><ref name=dale/><ref name=kirkman/>
 +
 
 +
==Cultural use==
 
==Photo Gallery==
 
==Photo Gallery==
 
<gallery widths=180px>
 
<gallery widths=180px>

Latest revision as of 12:21, 18 July 2022

Vernonia angustifolia
Vernonia angustifolia Gil.jpg
Photo taken by Gil Nelson
Scientific classification
Kingdom: Plantae
Division: Magnoliophyta – Flowering plants
Class: Magnoliopsida – Dicotyledons
Order: Asterales
Family: Asteraceae ⁄ Compositae
Genus: Vernonia
Species: V. angustifolia
Binomial name
Vernonia angustifolia
Michx.
VERN ANGU dist.jpg
Natural range of Vernonia angustifolia from USDA NRCS Plants Database.

Common name: Tall ironweed

Taxonomic notes

Varieties: Vernonia angustifolia Michaux var. angustifolia; Vernonia angustifolia Michaux var. mohrii S.B. Jones; Vernonia angustifolia Michaux var. scaberrima (Nuttall) A. Gray.[1]

Description

A description of Vernonia angustifolia is provided in The Flora of North America.

Distribution

Ironweed is found throughout the southeastern coastal plains region from North Carolina to Florida to Mississippi.[2]

Ecology

Habitat

In the Coastal Plain region, V. angustifolia can be found in sand pine scrubs, longleaf pine-wiregrass flatwoods, edges of meadows, pine-turkey oak flats, longleaf pine savannas, mixed woodlands adjacent to floodplains, annually burned pinelands, longleaf pine-sedge-andropogon savannas, slash pine-wiregrass flats, oak scrubs, second growth hardwoods, cabbage palm hammocks, annually burned upland pines[3][4] and sandhill communities.[5] A study exploring longleaf pine patch dynamics found V. angustifolia to be most strongly represented within stands of longleaf pine that are between 90-180 years of age.[6] This species can also be found along roadsides, power line corridors, bulldozed pine-oak scrubs, and clobbered slash pine forests. Soil types include sandy loam, loose sand, loamy sands, sandy peat[4], and Utisols[7] V. angustifolia is frequent and abundant in the North Florida Subxeric Sandhills community type and is an indicator species for the Clayhill Longleaf Woodlands community type as described in Carr et al. (2010).[8]

V. angustifolia reduced its occurrence in response to agriculture-based soil disturbance in South Carolina's historically longleaf communities.[9] It has shown resistance to regrowth in reestablished pinelands that were disturbed by agricultural practices, making it a possible indicator species for remnant woodlands.[10] V. angustifolia became absent in response to military training in west Georgia pinelands.[11] It also decreased its occurrence in response to soil disturbance by agriculture in southwest Georgia.[12]

Associated species include Aristida, Serenoa repens, Ilex glabra, Liatris, Andropogon, Panicum, and Leptoloma cognata.[4]

Phenology

V. angustifolia is a fall forb.[13] Showy-flowered sandhill species.[5] It has been observed flowering in January and June through October and fruits June through October.[4][14]

Seed dispersal

This species is thought to be dispersed by wind.[15]

Seed bank and germination

Less than 1% of V. angustifolia seeds remained viable after two years of burial.[7] So V. angustifolia does not have a short-term persistent soil seed bank and has little seed dormancy.[7]

Fire ecology

Vernonia angustifolia can live in areas frequently burned[7] as shown in populations on the Pebble Hill plantation of north Florida and Wade Tract of south Georgia that have been known to persist through repeated annual burns.[16][17]

Herbivory and toxicology

Vernonia angustifolia has been observed with leafcutting bees such as Megachile mendica (family Megachilidae).[18] In Southeastern pine savannas, V. angustifolia was found in 6.25% of the active gopher tortoise (Gopherus polyphemus) burrows[3] and is a nectar plant for native pollinators.[19]

Conservation, cultivation, and restoration

V. angustifolia should avoid soil disturbance by military training and agriculture to conserve its presence in pine communities.[9][10][11][12]

Cultural use

Photo Gallery

References and notes

  1. Weakley, A.S. 2015. Flora of the southern and mid-atlantic states. Working Draf of 21 May 2015. University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.
  2. Denhof, Carol. 2013. Understory Plant Spotlight Tall Ironweed Vernonia angustifolia Michx. The Longleaf Leader. Vol. VI. Iss. 4. Page 9
  3. 3.0 3.1 Birkhead, R. D., C. Guyer, et al. (2005). "Patterns of folivory and seed ingestion by gopher tortoises (Gopherus polyphemus) in a southeastern pine savanna." American Midland Naturalist 154: 143-151.
  4. 4.0 4.1 4.2 4.3 Florida State University Robert K. Godfrey Herbarium database. URL: http://herbarium.bio.fsu.edu. Last accessed: July 2015. Collectors: Loran C. Anderson, Robert K. Godfrey, Nancy E. Jordan, R. Kral, K. Craddock Burks, Andre F. Clewell, P. L. Redfearn, Samuel B. Jones, Richard S. Mitchell, John C. Ogden, H. E. Grelen, James D. Ray, Jr., Gwynn W. Ramsey, E. S. Ford, C. Jackson, Robert L. Lazor, John D. Lazor, Gary R. Knight, Rodie White, R. A. Norris, R. Komarek, M. Davis, MacClendons, G. Wilder, Cecil R Slaughter. States and Counties: Florida: Bay, Calhoun, Citrus, Columbia, Duval, Escambia, Flagler, Franklin, Gadsden, Hernando, Highlands, Jackson, Lake, Leon, Liberty, Martin, Nassau, Okaloosa, Santa Rosa, Seminole, Suwannee, Taylor, Wakulla, Washington. Georgia: Baker, Coffee, Grady, Thomas. Compiled by Tall Timbers Research Station and Land Conservancy.
  5. 5.0 5.1 Heuberger, K. A. and F. E. Putz (2003). "Fire in the suburbs: ecological impacts of prescribed fire in small remnants of longleaf pine (Pinus palustris) sandhill." Restoration Ecology 11: 72-81.
  6. Mugnani et al. (2019). “Longleaf Pine Patch Dynamics Influence Ground-Layer Vegetation in Old-Growth Pine Savanna”.
  7. 7.0 7.1 7.2 7.3 Coffey, K. L. and L. K. Kirkman (2006). "Seed germination strategies of species with restoration potential in a fire-maintained pine savanna." Natural Areas Journal 26: 289-299.
  8. Carr, S.C., K.M. Robertson, and R.K. Peet. 2010. A vegetation classification of fire-dependent pinelands of Florida. Castanea 75:153-189.
  9. 9.0 9.1 Brudvig, L.A. and E.I. Damchen. (2011). Land-use history, historical connectivity, and land management interact to determine longleaf pine woodland understory richness and composition. Ecography 34: 257-266.
  10. 10.0 10.1 Brudvig, L.A., E Grman, C.W. Habeck, and J.A. Ledvina. (2013). Strong legacy of agricultural land use on soils and understory plant communities in longleaf pine woodlands. Forest Ecology and Management 310: 944-955.
  11. 11.0 11.1 Dale, V.H., S.C. Beyeler, and B. Jackson. (2002). Understory vegetation indicators of anthropogenic disturbance in longleaf pine forests at Fort Benning, Georgia, USA. Ecological Indicators 1(3):155-170.
  12. 12.0 12.1 Kirkman, L.K., K.L. Coffey, R.J. Mitchell, and E.B. Moser. Ground Cover Recovery Patterns and Life-History Traits: Implications for Restoration Obstacles and Opportunities in a Species-Rich Savanna. (2004). Journal of Ecology 92(3):409-421.
  13. Kirkman, L. K., K. L. Coffey, et al. (2004). "Ground cover recovery patterns and life-history traits: implications for restoration obstacles and opportunities in a species-rich savanna." Journal of Ecology 92: 409-421.
  14. Nelson, G. PanFlora: Plant data for the eastern United States with emphasis on the Southeastern Coastal Plains, Florida, and the Florida Panhandle. www.gilnelson.com/PanFlora/ Accessed: 15 DEC 2016
  15. Kirkman, L. Katherine. Unpublished database of seed dispersal mode of plants found in Coastal Plain longleaf pine-grasslands of the Jones Ecological Research Center, Georgia.
  16. Robertson, K.M. Unpublished data collected from Pebble Hill Fire Plots, Pebble Hill Plantation, Thomasville, Georgia.
  17. Platt, W.J., R. Carter, G. Nelson, W. Baker, S. Hermann, J. Kane, L. Anderson, M. Smith, K. Robertson. 2021. Unpublished species list of Wade Tract old-growth longleaf pine savanna, Thomasville, Georgia.
  18. Discoverlife.org [1]
  19. Denhof, Carol. 2013. Understory Plant Spotlight Tall Ironweed Vernonia angustifolia Michx. The Longleaf Leader. Vol. VI. Iss. 4. Page 9