Spring Bartonia; Coastal Plain Endemic

Bartonia verna flowers (03/11/15)

Spring Bartonia (Bartonia verna) is an unexpected member of the Gentian family that appears in early spring. One of the many species first discovered by Andre Michaux, populations are restricted, or endemic, to the outer coastal plain of the southeastern US. The northernmost range consists of a single population located near VA Beach (Belden etal. 2004, reported in Castanea). Over half of the states where it has been documented consider it to be rare, including North Carolina.  A couple of the other states (MS, AL) have not explicitly considered its rarity, but like surrounding states it is almost certainly very restricted in those areas; Florida is the only state where the species is widespread (http://plants.usda.gov/core/profile?symbol=Bave2)

Spring Bartonia habitat at a site in South Carolina (03/11/15);
Pond Cypress depression pond with extensive standing water at flowering time

Sorrie & Weakley 1999 consider Bartonia's range generally synonymous with longleaf pine. The local habitat often includes wetland margins such as the example shown above on the Francis Marion National Forest.  The flowering Bartonia individuals located at this site occurred adjacent to pitcher plants, especially the Hooded Pitcher (Sarracenia minor), and Peanut-Grass (Amphicarpum muhlenbergianum). 

Bartonia verna multi-floral stem just opening

Bartonia verna in several inches of standing water; amidst brown stems of  Peanut-Grass

All Bartonia species (we have 3 in our area) are similar in having reduced leaves and root characteristics which may suggest a dependence on mychorrizal relationships to gain nutrients. Although B. verna has not been studied, Cameron & Bolin (2010) found that Bartonia virginica plants were enriched in carbon and nitrogen relative to surrounding vegetation and suggest that species is at least partially mycoheterotropic.

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Large-flowered Milkweed (Asclepias connivens)

Large-flowered Milkweed is one of the more distinctive milkweeds of the southeastern states, due to the unusually large, deeply cupped, individual flowers, that may reach nearly an inch across.

Individual flower (corona) of Asclepias connivens, displaying the "connivent" hood

Phylogentically, A. connivens is intermixed with African Milkweed species in clades developed by Fishbein (1996), providing some suggestion that our North American species may be derived from Africa; perhaps this implies this is also one of our more ancient species?

Large-flowered milkweed is a relatively narrow southeastern coastal plain endemic, ranging from extreme southeastern SC through coastal GA, into extreme southern AL, and across most of Florida, In the northern Florida panhandle, Asclepias connivens can be found in poorly drained, silty soil habitats that have been called wet flatwoods or prairies (Carr 2007); these sites have sparse tree canopies and well developed herbaceous layers.  The images included here are from two regularly burned sites taken on the same date. Plants at the most recently burned site were somewhat delayed in flowering compared to the site burned earlier in the season.

A. connivens coming into bloom in
standing water, recently burned savanna
(July 04, 2014)

A. connivens flowering in dense sward of grasses and herbs
under sparse canopy of longleaf pine
(July 04, 2014)

One of the sites could also be called a "wet savanna".  It had a sparse tree canopy of longleaf pine and a few Pond Cypress (Taxodium ascendans), including the two tallest stems shown in the midground below.  Some naturally occurring slash pine (Pinus elliotii) were present (seeding in from the adjacent forested wetland), but most of the smaller stems were killed by the last prescribed fire. In addition to numerous stems of Large-flowered Milkweed other notable species included Toothache Grass (Ctenium aromaticum), Parrot Pitcher Plant (Sarracenia psittacina), Pale Grass Pink (Calopogon pallidus), and Tracy's Sundew (Drosera tracyi)

Awesome wet savanna on St. Marks National Wildlife Refuge
Thanks to Jeff Glitzenstein for getting me there!

References:

Carr, S.C. 2007. Floristic and Environmental Variation of Pyrogenic Pinelands in the Southeastern Coastal Plain: Description, Classification, and Restoration. PhD Dissertation.

Fishbein, M.  1996. Phylogenetic Relationships of North American Asclepias and the Role of Pollinators in the Evolution of the Milkweed Inflorescence.  PhD Dissertation.

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A few Southeastern Coastal Plain endemics

Shiny Woodoats (Chasmanthium nitidum)
Wet hardwood hammock,
limestone close to surface
St. Marks NWR, July 2014 

Probably the rarest Woodoats grass or Chasmanthium species in North America, the natural range of Shiny Woodoats (Chasmanthium nitidum) is almost entirely found in Florida. The grass barely finds its way into NC where it is considered threatened, being known only from Pender County. 

Chasmanthium latifolium;
the most widespread member of the genus

Scareweed (Baptisia simplicifolia)
Pine Flatwoods, regularly burned
St. Marks NWR, July 2014

One of the Wild Indigos,  or sometimes called "Scareweed", Baptisia simplicifolia is a narrow endemic confined to a couple counties in north Florida's panhandle.

Limited to open pinelands, this is one of the many fire-adapted species found in longleaf pine flatwoods. At the end of the growing season, stems break off above ground and the plant blows around like tumbleweed, helping to distribute seeds still found in the capsules. The vast majority of the world's population is found on the Apalachicola National Forest.

   

Eurybia eryngiifolia 
Apalachicola National Forest
July 2014

Bristly heads and leaves of Eurybia eryngiifolia

                                                                                                                     












Thistle-leaved Aster (Eurybia eryngiifolia) is nearly endemic to the Florida panhandle, just barely extending into adjacent Georgia & Alabama. It is another pine flatwoods & fire-adapted species, closely associated with longleaf pine.  The scientific epithet (eryngiifolia) is a clear reference to the vegetative similarity to Rattlesnake Master (Eryngium yuccifolium)

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