Natives by ZIP

Native plants recorded in your state and county

Grass or grass-like · Poaceae

Purpletop tridens

Tridens flavus · includes its varieties and subspecies

Purpletop tridens is recorded as native to 35 states and territories in Kew’s World Checklist of Vascular Plants and USDA PLANTS, and recorded in 1,233 counties of those states by USDA PLANTS.

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.

Key facts · USDA PLANTS

Purpletop tridens at a glance

Native in
1,233 counties, across 35 states and territories
Estimated cold hardiness
Zone 5a PLANTS minimum temperature −23°F
Mature height
2.5 ft PLANTS mature height
Light and water
Full sun (shade-intolerant) Low water use

Estimated cold hardiness: zone 5a. PLANTS gives a minimum temperature of −23°F; zone 5a winters bottom out at −20°F, the coldest half-zone that stays within that limit.

Purpletop tridens is recorded as native to 35 states and territories in Kew’s World Checklist of Vascular Plants and USDA PLANTS, and recorded in 1,233 counties of those states by USDA PLANTS.

Counties where it is native

The 15 counties with the most ZIP codes among the 1,233 where it is listed.

Native counties by state

Growing traits

Values from the PLANTS characteristics record. “Not recorded” means PLANTS has no value; nothing here is estimated except the zone.

Growth

Growth habit
Graminoid
Duration
Perennial
Mature height
2.5 ft
Growth rate
Moderate
Growth form
Bunch
Shape
Erect
Lifespan
Short
Active growth period
Summer

Light and water

Shade tolerance
Intolerant (full sun (shade-intolerant))
Moisture use
Low water use
Drought tolerance
High
Tolerance of waterlogged soil
Low
Precipitation range
17 to 60 in per year

Soil

Soil textures
Coarse, medium and fine
pH range
4.5 to 6.5
Lime (CaCO₃) tolerance
Low
Salinity tolerance
None
Fertility requirement
Low
Minimum root depth
10 in

Climate

Minimum temperature
−23°F
Estimated cold hardiness
Zone 5a and warmer
Minimum frost-free days
150
Fire tolerance
High

Flowers, leaves and fruit

Flower color
Yellow
Showy flowers
No
Bloom period
Late Summer
Foliage color
Green
Showy in fall
Yes
Keeps leaves
No
Fruit color
Brown

Other

Toxicity
None
Nitrogen fixation
None
Nursery availability
Contracting Only
Family
Poaceae
PLANTS symbol
TRFL2

Is it native where you live?

Matches your ZIP to the county it mostly lies in, then lists the plants recorded as native to your state (Kew’s World Checklist and USDA PLANTS) and recorded in that county by USDA PLANTS.

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.
Scope
Tridens flavus (PLANTS symbol TRFL2), including 2 varieties and subspecies folded into the species.
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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