Heterotheca villosa var. ballardii

(Rydberg) Semple

Novon 4: 53. 1994.

Endemic
Basionym: Chrysopsis ballardii Rydberg Brittonia 1: 100. 1931
Treatment appears in FNA Volume 20. Treatment on page 251. Mentioned on page 250.

Stems ascending to erect, 22–50 cm, moderately to densely strigose, eglandular, often abundantly long-hirsute. Distal cauline leaf blades oblong, (18–)22–34(–42) × 4.3–9.3(–12.5) mm, little reduced distally, bases rounded, margins flat, faces moderately strigose (hairs usually not obscuring faces, 20–56(–70)/mm2), eglandular. Heads (2–)4–16(–24), in corymbiform arrays. Peduncles (5–)12–47(–67) mm, moderately to densely hispido-strigose, eglandular; bracts subtending heads leafy, oblanceolate, often exceeding involucres. Involucres broadly campanulate, (5.5–)6.5–9.3 mm. Phyllaries narrowly triangular-lanceolate, moderately to densely strigose, eglandular to sparsely glandular, margins often reddish purple distally. Ray florets (12–)17–30 (avereaging 21), laminae (8.5–)9.9–14.5 mm (averaging 11.5 mm; showy). 2n = 36.


Phenology: Flowering (Jun–)Jul–Aug(–Oct).
Habitat: Dry sandy clay, thin silty loam, sandy loam, gravel soils, dry, rocky, granite-gravel soils, prairies, fields, roadsides, railroad rights-of-way
Elevation: 300–2300 m

Distribution

V20-546-distribution-map.gif

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

Discussion

Variety ballardii grows in the northeastern Great Plains; it is rare and probably introduced in Colorado, Montana, and northwestern Ontario. In its typical, large-leaved and many-rayed form, var. ballardii is quite distinct. It is distinguished by its rounded leaf bases, indument of short hairs, eglandular, and large, many-rayed heads often subtended by one or more large, narrow, leaflike peduncle bracts. Plants of var. ballardii are sufficiently similar to those of var. foliosa that the two taxa might be treated as convarietal under the name var. foliosa. V. L. Harms (2003) treated the Saskatchewan plants as members of a more broadly defined var. villosa.

Selected References

None.

Lower Taxa

None.
John C. Semple +
(Rydberg) Semple +
Chrysopsis ballardii +
Alta. +, Man. +, Ont. +, Sask. +, Colo. +, Minn. +, Mont. +, Nebr. +, N.Dak. +  and S.Dak. +
300–2300 m +
Dry sandy clay, thin silty loam, sandy loam, gravel soils, dry, rocky, granite-gravel soils, prairies, fields, roadsides, railroad rights-of-way +
Flowering (Jun–)Jul–Aug(–Oct). +
Chrysopsis villosa +, Diplogon villosum +  and Diplopappus villosus +
Heterotheca villosa var. ballardii +
Heterotheca villosa +
variety +