Spermatophytes (seed plants): Angiosperms (flowering plants): Eudicots: Core Eudicots: Asterids: Campanulids: Asterales
WEAKLEY'S FLORA OF THE SOUTHEASTERN US (4/24/22):
Erigeron sumatrensis
FAMILY
Asteraceae
Go to FSUS key
Dig deeper at SERNEC, a consortium of southeastern herbaria.
(?)
PLANTS NATIONAL DATABASE:
Conyza floribunda
FAMILY
Asteraceae
INCLUDED WITHIN Floristic Synthesis of North America. BONAP (Kartesz, 2015)
Erigeron sumatrensis
SYNONYMOUS WITH Floristic synthesis of North America. BONAP (Kartesz, 2010)
Conyza floribunda
SYNONYMOUS WITH Flora of North America north of Mexico, vol. 19-20-21 (2006)
Conyza floribunda
(?) Homotypic synonym
Conyza sumatrensis
COMMON NAME:
Tropical Horseweed, Sumatran Fleabane, Guernsey Fleabane
To see larger pictures, click or hover over the thumbnails.
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JK Marlow jkm220906_9689
September Greenville County SC
Bald Rock Heritage Preserve
The tall columnar habit (characteristically 4-6' tall) of E sumatrensis makes it conspicuous, per Notes on the occurrence of Erigeron sumatrensis (Asteraceae) in Georgia (Nesom, 2018).
)
JK Marlow jkm220906_9691
September Greenville County SC
Bald Rock Heritage Preserve
Capitulescence [compound inflorescence, as in Asteraceae] usually paniculate-thyrsoid, per Erigeron floribundus and E. sumatrensis (Asteraceae) in the USA and Mexico (Nesom, 2018).
)
JK Marlow jkm220906_9694
September Greenville County SC
Bald Rock Heritage Preserve
)
JK Marlow jkm220909_9773
September Greenville County SC
Bald Rock Heritage Preserve
E. sumatrensis in September is mostly in fruit, while many E. canadensis are in full flower, per Notes on the occurrence of Erigeron sumatrensis (Asteraceae) in Georgia (Nesom, 2018).
)
JK Marlow jkm220909_9780
September Greenville County SC
Bald Rock Heritage Preserve
)
JK Marlow jkm220909_9786
September Greenville County SC
Bald Rock Heritage Preserve
)
JK Marlow jkm220909_9789
September Greenville County SC
Bald Rock Heritage Preserve
)
JK Marlow jkm220909_9794
September Greenville County SC
Bald Rock Heritage Preserve
Involucre densely pubescent, vs that of E. canadensis or pusillus glabrous or sparsely pubescent, per Weakley's Flora (2022).
)
JK Marlow jkm220909_9797
September Greenville County SC
Bald Rock Heritage Preserve
)
JK Marlow jkm220909_9798
September Greenville County SC
Bald Rock Heritage Preserve
Cauline leaves characteristically narrowly lanceolate-elliptic to lanceolate or oblanceolate, per Weakley's Flora (2022).
)
JK Marlow jkm220910_9845
September Greenville County SC
Bald Rock Heritage Preserve
Conyza sumatrensis is an obnoxious weed, emerging as an invasive species globally, per Seed germination ecology of Conyza sumatrensis populations stemming from different habitats and implications for management (Yanyun et al., 2021).
)
JK Marlow jkm220910_9848
September Greenville County SC
Bald Rock Heritage Preserve
)
JK Marlow jkm220910_9850
September Greenville County SC
Bald Rock Heritage Preserve
)
JK Marlow jkm220910_9853
September Greenville County SC
Bald Rock Heritage Preserve
Fruiting receptacles 1.5-2.5mm wide, weakly but distinctly alveolate ["honeycombed"], per Erigeron floribundus and E. sumatrensis (Asteraceae) in the USA and Mexico (Nesom, 2018).
)
Steve Marlow snm_090922_0115
September Greenville County SC
Bald Rock Heritage Preserve
WEAKLEY'S FLORA OF THE SOUTHEASTERN US (4/24/22):
Erigeron sumatrensis
FAMILY
Asteraceae
(?)
PLANTS NATIONAL DATABASE:
Conyza floribunda
FAMILY
Asteraceae
INCLUDED WITHIN
Floristic Synthesis of North America. BONAP (Kartesz, 2015)
Erigeron sumatrensis
SYNONYMOUS WITH
Floristic synthesis of North America. BONAP (Kartesz, 2010)
Conyza floribunda
SYNONYMOUS WITH
Flora of North America north of Mexico, vol. 19-20-21
Conyza floribunda
(?)
Homotypic synonym
Conyza sumatrensis
4637
Forb
Annual
Habitat: Disturbed areas, per Weakley's Flora
Non-native: Paleotropics
Uncommon in GA, rare in SC
CLICK HERE to see a map, notes, and images from Weakley's Flora of the Southeastern US.
LEAVES:
Simple
Alternate (basal leaves usually absent or withered at flowering)
Margins usually entire but can be fairly toothed
FLOWER:
Spring/Summer/Fall
Disc: White to pale yellowish
Rays: Absent? very tiny (less than 0.3mm)?
Inferior ovary
Disc flowers bisexual & fertile/ Ray flowers pistillate & fertile
FRUIT:
Spring/Summer/Fall?
Achene
TO LEARN MORE about this plant, look it up in a good book!
If a search such as "Carex leptalea var. leptalea" doesn't deliver the results you want, try "Carex leptalea".
Or, to minimize chances of a misspelling, try just "Carex le".
Less is more: If "pencil flower" doesn't deliver the results you want, try "pencil".