Iva axillaris Pursh

Family: Asteraceae, Tribe: Heliantheae

Pertinent Synonyms & Notes (particularly those used in California; go to GRIN for other synonyms)

Iva axillaris ssp. robustior (Hook.) Bassett

Pertinent Common Names (particularly those used in California; go to GRIN for other common names)

povertyweed, poverty sumpweed

Primary Disseminule Type


Description (diagnostics are in brown)

Fruit a cypsela, obovate to obtriangular, slightly curved near base, mildly compressed, cross-section elliptic with rounded to narrowed ends or trigonous to quadrangular, (2)2.5–3 mm long x 1.1–1.8 mm wide x 1–1.6 mm thick. Surface glabrous, brown to nearly black, covered with minute glistening bumps. Pappus none.

Style base missing or inconspicuous to present as a small stump, surrounded by the small (0.1–0.2 mm diameter) whitish ring that is the apical scar.

Fruit attachment scar basal, thin (compressed), often crescent-shaped, light-colored.

Risk Assessment (codes in yellow or red indicate cause for concern; assessments are current as of mid-2011; click AUQP, NZBORIC, or NZBPI for access to the most recent versions of these databases and possible assessment changes)