North Carolina Botanical Garden

Plant Index

Scientific Name:
Common Name:
Genus:
Family:

Trichostema dichotomum

Trichostema dichotomum L.

forked bluecurls, common blue curls

Trichostema dichotomum (Forked Bluecurls)

Image ID: 8228
Image by: Parkins, Grant Morrow
Image Collection: NCBG Digital Library

PLANT INDEX

ID_PLANT: TRDI2
SCIENTIFIC NAME: Trichostema dichotomum
Include in WOTAS: 1
Publish to Web: 1
Last Modified: 2020-01-03

GENUS INDEX

GENUS CODE: TRICH9
GENUS SCIENTIFIC: Trichostema
GENUS AUTHORITY: L.
GENUS COMMON: Bluecurls
GENUS SUMMARY: A genus of about 18 species, shrubs, annual and perennial herbs, of temperate North America (especially diverse in w. North America, with a second center of diversity in se. North America). Morphology, pollen, and phytogeography suggest the plausible recognition of Trichostema section Orthopodium (which includes this species and several from w. North America) as Isanthus, a genus distinct from section Trichostema (which includes all other eastern North American species).
GENUS IDENTIFICATION:
GENUS REFERENCES: Weakley (in prep.)=Z; Lewis (1945)=Y; Harley et al. in Kadereit (2004).

FAMILY INDEX

FAMILY CODE: LAMIAC
FAMILY SCIENTIFIC: Lamiaceae
FAMILY AUTHORITY: Lindley 1836 or LABIATAE A.L. de Jussieu 1789
FAMILY COMMON: Mint Family
FAMILY SUMMARY: A family of about 230-250 genera and 6700-7170 species, herbs, shrubs, vines, and trees, cosmopolitan. The placement in the Lamiaceae of several genera traditionally placed in Verbenaceae (e.g. Clerodendrum) is strongly supported by several lines of evidence.
FAMILY REFERENCE: Harley et al. in Kadereit (2004).

NCBG DESCRIPTIVES

INTRO: Erect annual found in dry woodlands, disturbed areas and thin soils around rock outcrops.
STEMS: Stems 4-angled, branched, hairy and with abundant long-stalked glands.
LEAVES: Leaves opposite, petiolate to sessile, elliptic and bluntly pointed, 1/2-2 1/2 in. long, minutely hairy and glandular.
INFLORESCENCE:
FLOWERS: Flowers in a terminal panicle, with 2 leaf-like bracts at the base of each 1- to 3-flowered stalk; dark blue to purple; about 1/2 in. long; bilaterally symmetric; consisting of 5 spreading lobes, the 4 upward-pointing ones similar in size and shape, and the longer downward-pointing one with a blue-purple-spotted white patch; 4 long stamens curl above.
FRUITS:
COMMENTS:
HEIGHT: 1-2 ft.

DURATION: Annual
HABIT: Herb

LEAF ARRANGEMENT: Opposite
LEAF COMPLEXITY: Simple
LEAF RETENTION:

FLORAL CHARACTERISTICS
SYMMETRY: Bilateral (Zygomorphic)
BLOOM TIME: Aug-Nov

Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
						x	x	x	x	x

BLOOM COLOR: Blue

White	Red	Pink	Orange	Yellow	Green	Blue	Lavender	Purple	Violet	Brown	Not Applicable
						x		x

FRUITING PERIOD:

DISTRIBUTION
HABITAT TYPE: Dry forests, Outcrops and glades, Woods margins
NATIVE RANGE: eastern North America

HORTICULTURAL
Plant Sale Text: Forked bluecurls is a delicate annual that is covered with small but elaborate blue-purple flowers. Its common name refers to the long stamens that curl over at the top of the flower. Blooming late summer to fall, this species produces many flowers over the course of the season, though each flower lasts less than a day. Trichostema dichotomum is in the mint family and is attractive to pollinators, especially native bees. Forked bluecurls readily self-sows, though does not like competition,so give it a little space and you may be rewarded with a bountiful stand of forked bluecurls. It is typically found in dry woodlands, woodlands margins, prairies and disturbed areas.

Bloom Table Text:

NCBG Location:

Cultural Notes:

SOIL MOISTURE: Dry, Average
LIGHT EXPOSURE: Sun, Part Shade
MINIMUM HARDINESS ZONE: 5
MAXIMUM HARDINESS ZONE: 11
GERMINATION CODE: 5
WILDLIFE VALUE: Bee Friendly
DEER RESISTANCE:

GRIM COLLECTIONS

Coll_id	Project	Collection date	Collector	Action
823	SOS	2016-10-26	Flood	View
832	SOS	2016-10-31	Dakar	View
1357	HORT	2006-10-11	Bryan	View
1689	HORT	2005-01-01	Bryan	View
2274	NPMD	2019-10-01	Touloupas	View
2279	NPMD	2019-10-01	Touloupas	View

GRIM ACCESSIONS

acc_id	acc_num	acc_dt	coll_id	Action
2680	1987-0143			View
4163	1992-0319			View
5690	1995-0814			View
6348	1995-1480			View

GRIM PLANTINGS

plt_num	acc_id	loc_num	pers_num	inst_dt	Action
6491	4163	200	NCBG staff	1993-03-01	View
8204	5690	204	NCBG staff	1993-01-01	View
9003	6348	2	NCBG staff	0000-00-00	View
12813	0	15	Liloia	0000-00-00	View
13030	0	21	Liloia	0000-00-00	View

USDA PLANTS DATABASE

USDA Symbol: TRDI2
USDA Common Name: Forked Bluecurls
Native Status: L48 (N), CAN (N)
Distribution: USA (AL, AR, CT, DC, DE, FL, GA, IA, IL, IN, KY, LA, MA, MD, ME, MI, MO, MS, NC, NH, NJ, NY, OH, OK, PA, RI, SC, TN, TX, VA, VT, WV), CAN (ON, QC)
Duration: Annual
Growth Habit: Forb/herb

NATIONAL WETLAND INDICATOR STATUS

Region:	AGCP	AK	AW	CB	EMP	GP	HI	MW	NCNE	WMVE
Status:	UPL				UPL	FAC		UPL	UPL

This information is derived from the U.S. Army Corps of Engineers 2016 National Wetland Plant List, Version 3.3 (Lichvar, R.W., D.L. Banks, W.N. Kirchner, and N.C. Melvin. 2016. The National Wetland Plant List: 2016 wetland ratings. Phytoneuron 2016-30: 1-17. Published 28 April 2016. ISSN 2153 733X). Regions: AGCP-Atlantic and Gulf Coastal Plain, AK-Alaska, AW-Arid West, CB-Caribbean, EMP-Eastern Mountains and Piedmont, GP-Great Plains, HI-Hawaii, MW-Midwest, NCNE-Northcentral and Northeast, WMCV-Western Mountains, Valleys & Coast

WEAKLEY FLORA

SCIENTIFIC NAME: Trichostema dichotomum
COMMON NAME: Common Blue Curls
SYNONYMY: [= C, K, Mo, Pa, RAB, S, Va, W, WV, Z; > T. dichotomum var. dichotomum - F; >< T. dichotomum var. puberulum Fernald & Griscom - F; = T. dichotomum var. dichotomum - G; < T. dichotomum - WH3]
PHENOLOGY: Aug-Nov.
HABITAT: Dry woodlands, disturbed areas, thin soils around rock outcrops.
COMMENTS: ME, ON, QC, MI, and IA, south to FL and TX.
RANGE MAP: Trichostema dichotomum.png

Key to Map Symbols

ABOUT FAMILY (Weakley Flora)
Lamiaceae Lindley 1836 or LABIATAE A.L. de Jussieu 1789 (Mint Family)
SUMMARY: A family of about 230-250 genera and 6700-7170 species, herbs, shrubs, vines, and trees, cosmopolitan. The placement in the Lamiaceae of several genera traditionally placed in Verbenaceae (e.g. Clerodendrum) is strongly supported by several lines of evidence.
REFERENCE: Harley et al. in Kadereit (2004).

ABOUT GENUS (Weakley Flora)
Trichostema L. (Bluecurls)
SUMMARY: A genus of about 18 species, shrubs, annual and perennial herbs, of temperate North America (especially diverse in w. North America, with a second center of diversity in se. North America). Morphology, pollen, and phytogeography suggest the plausible recognition of Trichostema section Orthopodium (which includes this species and several from w. North America) as Isanthus, a genus distinct from section Trichostema (which includes all other eastern North American species).
REFERENCE: Weakley (in prep.)=Z; Lewis (1945)=Y; Harley et al. in Kadereit (2004).

HERBARIUM RESOURCES

SERNEC: Find Trichostema dichotomum in Southeast Regional Network of Experts and Collections (if available)
UNC SERNEC: Find Trichostema dichotomum in University of North Carolina Chapel Hill Herbarium - Southeast Regional Network of Experts and Collections (if available)

WEB RESOURCES

USDA: Find Trichostema dichotomum in USDA Plants
NPIN: Find Trichostema dichotomum in NPIN Database
FNA: Find Trichostema dichotomum in the Flora of North America (if available)
Google: Search Google for Trichostema dichotomum

IMAGE USE RECORDS

ID IMAGE: 8228 - Primary Image FloraQuest Plant Detail Page (Landscape Preferred)
ID IMAGE1: 19004 - Primary Image WOTAS
ID IMAGE2: 0 - Secondary Image WOTAS
ID IMAGE3: 21315 - Primary Image Plant Sale Sign (Landscape Only)
ID IMAGE4: 0 - Primary Image New Plant Sale Label (Portrait Only)