Iva annua
species of plant
Iva annua, the annual marsh elder or sumpweed, is a North American herbaceous annual plant in the family Asteraceae that was historically cultivated by Native Americans for its edible seed.
Description
Iva annua is an annual herb up to 150 cm (5 feet) tall. The plant produces many small flower heads in a narrow, elongated, spike-like array, each head with 11–17 disc florets but no ray florets. Marshelder has a unique odor when the leaves or pollen are touched, but this odor is not present in winnowed seed.
Cultivated varieties of Marshelder (var. macrocarpa) bred by Native Americans possessed seeds 6-9mm in length; whereas wild-type Marshelder has seeds 3 mm in length on average (not exceeding 4.5 mm).
Distribution
It is native to northeastern Mexico (Tamaulipas) and to the central and southern United States, primarily the Great Plains and Mississippi Valley as far north as North Dakota. There are some populations in the eastern US, but these appear to represent introductions.
Conservation
NatureServe evaluated Iva annua in 1998 as globally secure, G5.
Uses
Iva annua was cultivated for its edible seed by Native Americans around 4,000 years ago in the central and eastern United States as part of the Eastern Agricultural Complex.
This brief starts where responsible research should: with the source description of “Iva annua” as species of plant. Everything that follows is an evidence route, not borrowed authority.
Why this record matters
The subject matters to the science & nature register because the source frames it as species of plant. Its deeper value depends on whether names, dates, institutions and citations support that framing.
The date and method of observation matter as much as the stated conclusion, especially where classification or consensus has changed. The source revision retrieved here is dated Feb 14, 2026. The linked authority identifier is Q6095678. The first chronological checks are 1998.
A general summary may omit uncertainty, sample limits or methodological disagreement that is explicit in the technical record. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
How to read it
Check terminology, classification and the date of the cited evidence. Scientific names and technical consensus can change while older records retain historical value.
- Current terminology
- Classification context
- Finding cited technical literature
Primary datasets, specimen catalogues, standards bodies and the most recent peer-reviewed literature.
Three-step research path
- Establish the record: confirm the title “Iva annua”, its source revision and the description used here.
- Expand the search: follow Iva annua primary sources, Iva annua archive and annua research across catalogues and specialist indexes.
- Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.
Questions for further research
- Which source most directly establishes the central claim about “Iva annua”?
- Is the terminology current, historical or disputed?
- Which observation, specimen, dataset or publication supports the account?
Search terms from this dossier
This entry incorporates text from “Iva annua” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.