Native plants · Iowa

Native plants of Worth County

12 plant species are recorded as native to Iowa in Kew’s World Checklist of Vascular Plants and USDA PLANTS, and recorded in Worth County by USDA PLANTS. 6 of them have growing records you can filter by light, moisture, height and estimated cold hardiness.

County summary · USDA PLANTS and Kew WCVP

Worth County, Iowa

PLANTS records only 6 garden-ready natives here (under 30). County records are thin in some places; the Iowa list is a useful second check.

Native species: 12 Typical Iowa county: 44 (median of 99 counties)
Garden-ready natives: 6 Typical Iowa county: 24
Share by type (all 12 native species): Percent of the 12 native species in each growth type

Wildflower (forb) 50% (6)
Grass or grass-like 25% (3)
Fern 25% (3)

Wildflowers make up the largest share of the native list (50%), followed by grasses and grass-like plants (25%).

Recorded native ranges can include long-established populations that spread from gardens; check your state’s native plant society list for local guidance. How native status is decided.

ZIP codes mainly in this county fall in USDA hardiness zone 5a (2023 map).

The native plant list

Garden-ready natives 6

Native species with PLANTS growing records (height, light, moisture, minimum temperature). “—” means PLANTS has no value.

Garden-ready native plants of Worth County, Iowa
Plant	Type	Height	Light	Water use	Hardy to
big bluestem Andropogon gerardii	Grass or grass-like	6 ft	Sun	Low	Zone 2b
devil's beggartick Bidens frondosa	Wildflower (forb)	4 ft	Sun–part shade	Medium	Zone 12a
field horsetail Equisetum arvense	Fern	11 in	Sun–part shade	High	Zone 3a
fringed brome Bromus ciliatus	Grass or grass-like	4 ft	Shade-tolerant	Medium	Zone 7a
marsh muhly Muhlenbergia racemosa	Grass or grass-like	3 ft	Shade-tolerant	Medium	Zone 3b
smooth horsetail Equisetum laevigatum	Fern	5 ft	Sun	Low	Zone 3b

Other native species recorded here 6

PLANTS has no growing records for these, so light, moisture, height and zone filters cannot include them. Many are wild species seldom sold by nurseries.

big devils beggartick Bidens vulgata
bulblet-bearing water hemlock Cicuta bulbifera
Clayton's sweetroot Osmorhiza claytonii
golden zizia Zizia aurea
sensitive fern Onoclea sensibilis
yellow pimpernel Taenidia integerrima

Compared with Iowa

The typical county is the median of the 99 Iowa counties with PLANTS county records; the statewide figure counts every species native anywhere in the state. More species is not better or worse: counties differ in size, habitat and how thoroughly they have been surveyed.

Native species counts, Worth County and Iowa
Measure	Worth County	Typical county	Statewide
Native species	12	44	1,374
Garden-ready natives	6	24	496
Tree	0	—	110
Shrub	0	—	72
Wildflower (forb)	6	—	779
Grass or grass-like	3	—	298
Vine	0	—	55
Fern	3	—	60

Neighboring counties

Counties that share a ZIP code with Worth County.

Cerro Gordo County, IA 24 garden-ready
Mitchell County, IA 22 garden-ready
Winnebago County, IA 16 garden-ready

Source & data date

Source: USDA NRCS PLANTS Database: county distribution records, native status and plant characteristics. CC0 (public domain dedication, per the data.gov catalog record).; Kew’s World Checklist of Vascular Plants (WCVP): native or introduced status by state. CC BY 3.0.; USGS US-RIIS (ver. 2.0): species listed as introduced are excluded. CC0.
Citation: USDA, NRCS. 2026. The PLANTS Database (https://plants.usda.gov, 11/04/2026). National Plant Data Team, Greensboro, NC USA.; Govaerts R. (ed.) (2026). WCVP: World Checklist of Vascular Plants. Facilitated by the Royal Botanic Gardens, Kew. Data file dated 2026-06-04, http://sftp.kew.org/pub/data-repositories/WCVP/ (retrieved 2026-11-04). Paper: Govaerts R. et al. (2021) The World Checklist of Vascular Plants, a continuously updated resource for exploring global plant diversity. Scientific Data 8, 215.
Data date: Retrieved from PLANTS on November 4, 2026; WCVP data file dated June 4, 2026.
Zones: USDA Plant Hardiness Zone Map (2023) ZIP table: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed November 3, 2026. Plant zones on this site are our estimate, not the official map.
Scope: Worth County (county FIPS 19195), Iowa. 12 native species from PLANTS county distribution records; garden-ready = species with a PLANTS characteristics record.
Method: A species is listed when it is recorded as native to the state in Kew’s World Checklist of Vascular Plants and USDA PLANTS, and recorded in the county by USDA PLANTS. Species PLANTS labels both native and introduced are listed separately. Full method · All sources

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