Rudbeckia hirta

Rudbeckia hirta
Rudbeckia hirta flowerhead
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Eudicots
(unranked):	Asterids
Order:	Asterales
Family:	Asteraceae
Genus:	Rudbeckia
Species:	R. hirta
Binomial name
Rudbeckia hirta L.

Rudbeckia hirta (common names: Black-eyed Susan, Blackiehead, Brown Betty, Brown Daisy, Brown-eyed Susan (Rudbeckia triloba), Gloriosa Daisy, Golden Jerusalem, Poorland Daisy, Yellow Daisy, Yellow Ox-eye Daisy) is a flowering plant in the family Asteraceae. It is an upright annual (sometimes biennial or perennial) native to most of North America, and is one of a number of plants with the common name Black-eyed Susan with flowers having dark purplish brown centers.

The genus name honors Olaus Rudbeck, who was a professor of botany at the University of Uppsala in Sweden and was one of Linnaeus' teachers. The specific name refers to the trichomes (hairs) occurring on leaves and stems.^[1]

Growth

The plant can reach a height of 1 m. It has alternate, mostly basal leaves 10-18 cm long, covered by coarse hair. It flowers from June to August, with inflorescences measuring 5-8 cm in diameter (up to 15 cm in some cultivars), with yellow ray florets circling a brown, domed center of disc florets.^[2]

Varieties

There are four varieties:

• Rudbeckia hirta var. angustifolia. Southeastern United States (South Carolina to Texas).
• Rudbeckia hirta var. floridana. Florida, endemic.
• Rudbeckia hirta var. hirta. Northeastern United States (Maine to Alabama).
• Rudbeckia hirta var. pulcherrima. Widespread in most of North America (Newfoundland to British Columbia, south to Alabama and New Mexico; naturalized Washington to California).

Symbolism and uses

The Black-eyed Susan was designated the state Floral Emblem of Maryland in 1918.

Numerous cultivars have been selected for garden planting; some popular ones include 'Double Gold', 'Indian Summer', and 'Marmalade'.

The roots but not seedheads of Rudbeckia hirta can be used much like the related Echinacea purpurea. It is an astringent used as in a warm infusion as a wash for sores and swellings. The Ojibwa used it as a poultice for snake bites^[3] and to make an infusion for treating colds and worms in children. The plant is diuretic and was used by the Menominee and Potawatomi. ^[4][5] Juice from the roots had been used as drops for earaches.^[6]

The plant contains anthocyanins. ^[7]

Gallery

Inflorescence and involucral bracts	Rudbeckia hirta 'Indian summer'	Rudbeckia hirta 'Indian summer'	Rudbeckia hirta in southern Maine.
	Northern Crescent (Phyciodes cocyta) butterfly, Rideau River, Ottawa, Canada

Notes

1. ^ Andy's Northern Ontario Wildflowers: Native Meadow Wildflowers. Black-eyed Susan.
2. ^ Floridata: Rudbeckia hirta.
3. ^ Black-Eyed Susan
4. ^ Herbs
5. ^ Rudbeckia hirta
6. ^ Moerman. D. Native American Ethnobotany Timber Press. Oregon. 1998 ISBN 0-88192-453-9
7. ^ Cat.Inist

References

Wikimedia Commons has media related to: Rudbeckia hirta

Wikiversity has bloom time data for Rudbeckia hirta on the Bloom Clock

• Germplasm Resources Information Network: Rudbeckia hirta
• USDA Plant Profile: Rudbeckia hirta
• Rudbeckia hirta Large format diagnostic photographs
• A Tale of Two Susans non-scholarly essay on the etymology and history
• Knowlton Foote. 2001. Black-eyed Susan (Rudbeckia hirta L.). New York Flora Association. Newsletter Vol. 13.