Rudbeckia species

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Scientific Name Rudbeckia hirta USDA PLANTS Symbol RUHI2
Common Name Black-eyed Susan ITIS Taxonomic Serial No. 36765
Family Asteraceae (Sunflower) SEINet
Reference
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Description Life zones and habitat: Foothills to montane (5200 to 10000 ft.); various, usually in sandy soils of fields, pastures, open areas.
Plant: Erect annual or short-lived perennial, rigid, grooved stems 12 to 40 inches tall covered with long, rough hairs.
Leaves: Petiolate basal leaves 3 to 12 inches long; alternate, petiolate or sessile stem leaves 1-1/4 to 8 inches long; blades lanceolate to elliptic, not lobed, covered with coarse hairs.
Inflorescence: Solitary or loose arrays of 2 to 5 large composite flowers on long peduncles, up head to 3 inches across with 8 to 16 drooping yellow rays with lengthwise grooves; central disk often-flattened and dome-shaped, yellowish green to purplish brown.
Bloom Period: June to September.
References: "Flora of Colorado" by Jennifer Ackerfield, SEINet and www.americansouthwest.net.
BONAP Distribution Map
Colorado Status:
Native
Scientific Name Rudbeckia laciniata var. ampla USDA PLANTS Symbol RULAA
Common Name Golden Glow, Green-head Coneflower, Cut-leaf Coneflower ITIS Taxonomic Serial No. 530173
Family Asteraceae (Sunflower) SEINet
Reference
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Description Life zones and habitat: Foothills and montane (5000 to 9000 ft.); moist areas, streamsides, meadows, aspen groves, roadsides.
Plant: Erect, rigid perennial often in colonies, 2 to 7 feet tall, branched at base.
Leaves: Large basal and stem leaves, broadly ovate to lanceolate with toothed edges; lower leaves once or twice pinnately-divided into several segments or pinnatifid; upper leaves are undivided; stem leaves are alternate.
Inflorescence: Very large (up to 6-inces across) composite flower heads in branching clusters; 8 to 12 drooping rays; 150 to 300+ yellow or yellow-green disk florets on central, protruding disc; ovoid-shaped involucre with 8 to 15 wide, pointed phyllaries up to 3/4-inch long.
Bloom Period: June to September.
References: "Flora of Colorado" by Jennifer Ackerfield, www.americansouthwest.net and Flora of North America.
BONAP Distribution Map
Colorado Status:
Native
Scientific Name Rudbeckia occidentalis USDA PLANTS Symbol RUOC2
Common Name Western Coneflower ITIS Taxonomic Serial No. 36782
Family Asteraceae (Sunflower) SEINet
Reference
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Description Life zones and habitat: Plains to montane (3300 to 9200 ft.); moist, open meadows and woods, streamsides.
Plant: Perennial 2 to 5 feet tall with thick, rigid leafy stems.
Leaves: Petiolate basal leaves 5 to 12 inches long; alternate, petiolate or sessile stem leaves 2 tp 10 inches long; blades broadly ovate to lanceolate, not lobed with prominent central vein; margins entire or serrate, hairy undersides.
Inflorescence: One or more large dark brown cylindrical to conical or ovoid flower heads up to to 2 inches long, each with 200-500+ tiny 5-lobed disk florets, yellow but turning purplish brown and blooming from bottom to top; no ray florets; leafy bracts below.
Bloom Period: Summer to fall.
References: www.americansouthwest.net, SEINet and "Wildflowers of the Rocky Mountains" by Carl Schreier.
Note: Some of the images below are from above 10,000 ft., at a location south of Breckenridge, well above the expected altitude range.
BONAP Distribution Map
Colorado Status:
Native

© Tom Lebsack 2021