Helianthus nuttallii subsp. rydbergii

(Britton) R. W. Long

Brittonia 18: 77. 1966.

Common names: Rydberg’s sunflower
Endemic
Basionym: Helianthus rydbergii Britton Man. Fl. N. States, 993. 1901
Treatment appears in FNA Volume 21. Treatment on page 167.

Plants usually 100–250 cm. Leaves all or mostly opposite; blades lanceolate to nearly ovate, apices acute to obtuse, abaxial faces hispid to hispidulous. Phyllaries: abaxial faces ± glabrate or sparsely hairy (longer hairs 0.5–1 mm).


Phenology: Flowering late summer–fall.
Habitat: Open areas, sandy dry soils, wet places
Elevation: 200–1000 m

Distribution

V21-404-distribution-map.gif

Alta., Man., Ont., Que., Sask., Colo., Iowa, Minn., Mont., Nebr., N.Dak., S.Dak.

Discussion

Selected References

None.

Lower Taxa

None.
hairy +, glabrate +, hispid +  and hispidulous +
not tailed +, rounded +  and obtuse +
dark-brown +  and black +
pale +  and dark +
connate +  and distinct +
subequal +
scarious +
usually ovate +  and lanceolate +
usually deltate +  and lanceolate +
spiciform +, paniculiform +  and corymbiform +
indeterminate +  and determinate +
Edward E. Schilling +
(Britton) R. W. Long +
cuneate +
Helianthus rydbergii +
light +  and dark green +
4 cm40 mm <br />0.04 m <br /> (20 cm200 mm <br />0.2 m <br />) +
lanceolate;nearly ovate +
0.8cm;4cm +
winged;ribbed;winged;ribbed +
tuberculate +  and rugose +
barbellulate +  and barbellate +
Rydberg’s sunflower +
reddish +  and yellow +
0.5 cm5 mm <br />0.005 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
compressed +  and obpyramidal +
fertile +  and bisexual +
fertile +  and bisexual +
Alta. +, Man. +, Ont. +, Que. +, Sask. +, Colo. +, Iowa +, Minn. +, Mont. +, Nebr. +, N.Dak. +  and S.Dak. +
200–1000 m +
hairy +  and glabrous +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
Open areas, sandy dry soils, wet places +
in more or less corymbiform , paniculiform or spiciform , arrays +  and singly +
indeterminate +
homogamous +  and heterogamous +
each +  and sessile +
1 cm10 mm <br />0.01 m <br /> (2 cm20 mm <br />0.02 m <br />) +
hemispheric +
2 cm20 mm <br />0.02 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
sessile +  and petiolate +
triangular +
serrate +  and entire +
2-carpellate +
3-toothed +
0.8 cm8 mm <br />0.008 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
persistent +
0 +  and 2 +
coroniform +
1 cm10 mm <br />0.01 m <br /> (18 cm180 mm <br />0.18 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
Flowering late summer–fall. +
0.8 cm8 mm <br />0.008 m <br /> (1.6 cm16 mm <br />0.016 m <br />) +
30 +  and 38 +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
bearing subulate enations +, hairy +  and bristly +
flat;slightly convex +
lanceolate +  and aristate +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
exalbuminous +
procumbent +  and decumbent +
Scabrous (?) +, Hirsute (?) +, Hispid (?) +  and Glabrous (?) +
appendaged +  and truncate +
hirsutulous +  and glabrous +
papillate +
Undefined (tribe Undefined) subtribe Lagasceinae +
Helianthus nuttallii subsp. rydbergii +
Helianthus nuttallii +
subspecies +
campanulate +
toothed +  and entire +
300 cm3,000 mm <br />3 m <br /> (500 cm5,000 mm <br />5 m <br />) +
100 cm1,000 mm <br />1 m <br /> (400 cm4,000 mm <br />4 m <br />) +