Vascular Plants of North Carolina

Account for Common October-flower - Polygonella polygama (Ventenat) Engelmann & A. Gray

Section 6 » Order Polygonales » Family Polygonaceae

Author	(Ventenat) Engelmann & A. Gray
Distribution	Note that the species as described here is only a small portion of the "P. polygama" as described in most recent and older references. Weakley (2018) and a few others have pulled out P. croomii from this larger P. polygama; that species is essentially the western two-thirds of the overall range in NC. The strict-sense P. polygama is limited in NC to the Outer Coastal Plain. Lack of records from Onslow County seems odd. Disjunct to Moore County in the Sandhills, the specimen (at NCU) was ID by LeBlond and checked again in 2022 by Sorrie. A specimen from Gates County in 2020 was determined by Sorrie as this species, thus providing a first record for the northern half of the Coastal Plain; however, as it does occur in southeastern VA, a record from Gates County might not be that surprising after all. Coastal Plain, southeastern VA to southern FL and TX.
Abundance	Frequent to common in its rather small range, as compared with the broader range in NC for the similar P. croomii. Note that the NCNHP has a State Rank of S3S4 for the broad-sense P. polygama, not this entity here. Thus, the website editors have had to assign new State Rank for these two entities -- still using S3S4 for P. croomii, but only S2S3 for P. polygama, owing to a smaller range, limited mainly to 5 coastal counties.
Habitat	Xeric sandhills and Turkey Oak (Quercus laevis) ridges within the Longleaf Pine (Pinus palustris) ecosystem.
Phenology	Flowering and fruiting late August-November.
Identification	Common October-flower has suffruticose (semi-woody) stems that form masses of low "shrubs" 1-2 feet tall with straggly branches, and is quite showy when in flower. Above-ground portions become skeletons over the winter. The stems are woody, unlike our other jointweeds, except for P. croomii. That species can almost always be distinguished from the very similar Common October-flower by leaf shape and size; that species has linear to linear-spatulate leaves about 4-13 mm long and 0.5-1.2 mm wide; Common October-flower has wider leaves that are spatulate to linear-spatulate in shape, 7-30 mm long and 1-6 mm wide. See Weakley (2018) for additional characters, most of which are microscopic. Male plants have white corollas; females yellow-green.
Taxonomic Comments	A few recent authors have noted the genetic similarity of Polygonella to Polygonum and have lumped the two. Because the two can be easily told apart in the field, taxon editors, including Weakley (2018), prefer to recognize both genera. As mentioned above, the NCNHP uses the name of Polygonum pinicola.
Other Common Name(s)	October-flower (the name used for the combined P. polygama and P. croomii)
State Rank	[S2S3]
Global Rank	G4
State Status
US Status
USACE-agcp
USACE-emp

County Map - click on a county to view source of record.