Perennial Ragweed
Ambrosia psilostachya
Found in calcareous prairies (westwards); in loamy sandy soil of flats and slight depressions in periodically burned longleaf pine uplands; also in disturbed areas. Weakley, Flora of the Southeastern United States (2025), Florida edition What its natural habitat tells you
67
Strong
Native to Florida. How scores work Is it native here?
Profile 94%
- Height
- usually 1 to 2 feet tall
- Light
- Partial shade, Full sun
- Soil moisture
- Dry to moist
At a glance
- Life cycle
- Perennial
- Bloom
- July to November
JFMAMJJASOND
Not yet recorded · Spread · Leaves
Recorded in 12 Florida counties.
Natural habitats
Places it grows wild. Not a planting requirement. Each habitat page lists the plants and wildlife also found there.
1 of 2
Roadsides, fields and disturbed ground
Ground opened by people: roadsides, old fields, pastures, fencerows and lots.
Ecological relationships
Who uses this plant?
56CaterpillarsGenus host records with ranges including FL
Genus host records with ranges including FL · Ambrosia
- Achyra rantalisGarden Webworm Moth
- Adaina ambrosiaeAmbrosia Plume Moth, Ragweed Plume Moth
- Argyrotaenia velutinanaRed-Banded Leafroller Moth, Jack Pine Tube Moth
- Astrotischeria ambrosiaeellax
- Azenia obtusaObtuse Yellow
- Caenurgina erechteaClover Looper Moth, Common Grass Moth, Forage Looper
- Carmenta texanaTexana Clearwing Moth
- Chionodes mediofuscellaBlack-Smudged Chionodes
- Chlorochlamys chloroleucariaBlackberry Looper Moth
- Choristoneura rosaceanaOblique-Banded Leafroller Moth, Rosaceous Leaf Roller
Show all 56
- Condica sutorThe Cobbler, Cobbler Groundling
- Dichomeris juncidellaOrange-Dotted Dichomeris
- Dichomeris serrativittellaToothed Dichomeris
- Ephestiodes infimellaReddish Ephestiodes
- Epiblema otiosanaBidens Borer Moth
- Epiblema strenuanaRagweed Borer
- Eupithecia miserulataCommon Eupithacia, Common Pug
- Exelastis pumilioDwarf Plume Moth
- Helcystogramma chambersellaChambers' Twirler
- Hellinsia inquinatusBlack-Marked Plume Moth
- Herpetogramma bipunctalisSouthern Beet Webworm, Two-Spotted Herpetogramma
- Hypena scabraGreen Cloverworm Bomolocha, Black Snout
- Lascoria ambigualisAmbiguous Moth, Ambiguous Litter Moth
- Leptostales pannariaPannaria Wave
- Mythimna unipunctaArmyworm Moth, White Speck
- Ogdoconta cinereolaCommon Pinkband Groundling
- Ostrinia obumbratalisSmartweed Borer
- Papaipema cataphractaBurdock Border, Potato-Stalk Borer
- Pelochrista cataclystianaSolidaga Eucosma, Solidaga Pelochrista
- Pholisora catullusCommon Sootywing
- Plagiomimicus pityochromusBlack-Barred Brown, Ragweed Seedcropper
- Platynota stultanaOmnivorous Leafroller
- Pleuroprucha insulsariaCommon Tan Wave
- Polygonia interrogationisQuestion Mark
- Ponometia candefactaOlive-Shaded Bird-Dropping Moth
- Ponometia erastrioidesSmall Bird-Dropping Moth
- Rachiplusia ouGray Looper
- Schinia gracilentaIva Flower Moth, Slender Flower Moth
- Schinia rivulosaRagweed Flower Moth
- Schinia thoreauiThoreau's Flower Moth
- Scopula inductataSoft-Lined Wave
- Sparganothis sulfureanaSparganothis Fruitworm Moth, Sulfur Leafroller, False Yellow-Head
- Spilosoma virginicaVirginian Tiger Moth, Yellow Woolybear Moth, Yellow Bear
- Spragueia guttataSpotted Spragueia
- Spragueia jaguaralisCounfounding Spragueia
- Spragueia leoCommon Spragueia
- Spragueia onagrusBlack-Dotted Spragueia
- Synchlora frondariaSouthern Emerald
- Thyridopteryx ephemeraeformisEvergreen Bagworm Moth
- Tricholita signataSignate Quaker, Signate Groundcat
- Dejongia californicus
- Epiblema minutana
- Gnorimoschema saphirinella
- Omiodes simialis
- Paralobesia sambuci
- Paralobesia vernoniana
2BeesSoutheastern regional records
Southeastern regional records · Ambrosia
Individual names are not available yet.
Noori, Seltmann & Orr 2026, A curated and integrated dataset for exploring global bee-plant interactions (GloBI), Zenodo, CC BY 4.0
0Specialist beesPollen specialists
31BirdsRecorded genus food-resource interactions; not a state feeding claim
Recorded genus food-resource interactions; not a state feeding claim · Ambrosia
- Acanthis flammeaCommon Redpoll
- Agelaius phoeniceusRed-winged Blackbird
- Ammodramus savannarumGrasshopper Sparrow
- Anthus rubescensAmerican Pipit
- Anthus spragueiiSprague's Pipit
- Calcarius lapponicusLapland Longspur
- Calcarius pictusSmith's Longspur
- Cardinalis cardinalisNorthern Cardinal
- Colinus virginianusNorthern Bobwhite
- Columbina passerinaCommon Ground Dove
Show all 31
- Corvus brachyrhynchosAmerican Crow
- Dolichonyx oryzivorusBobolink
- Eremophila alpestrisHorned Lark
- Haemorhous mexicanusHouse Finch
- Junco hyemalisDark-eyed Junco
- Loxia curvirostraRed Crossbill
- Loxia leucopteraWhite-winged Crossbill
- Melospiza lincolniiLincoln's Sparrow
- Melospiza melodiaSong Sparrow
- Molothrus aterBrown-headed Cowbird
- Ortalis vetulaPlain Chachalaca
- Pinicola enucleatorPine Grosbeak
- Plectrophenax nivalisSnow Bunting
- Quiscalus quisculaCommon Grackle
- Rhynchophanes mccowniiMcCown's Longspur
- Sialia sialisEastern Bluebird
- Sturnus vulgarisEuropean Starling
- Turdus migratoriusAmerican Robin
- Tympanuchus phasianellusSharp-tailed Grouse
- Zenaida macrouraMourning Dove
- Zonotrichia querulaHarris's Sparrow
Direct food only: birds recorded eating this genus across North America. Caterpillars on host plants also feed nesting birds. NC Native Plant Society: butterfly gardening
No records yet · Ants · Beetles · Flies · Adult butterflies / moths · Other wasps · Other insects
Growing and identification
Plant details
- Family
- Asteraceae
- Flower color
- White or green
Safety has not been reviewed for this plant; check toxicity and thorns before planting.
Growing sources and scope
- Bloom · “July to November” · Weakley, Flora of the Southeastern United States (2025), Carolinas & Georgia edition · Carolinas and Georgia
- Flower color · “White or green” · Lady Bird Johnson Wildflower Center
- Height · “usually 1 to 2 feet (30-60 cm) tall” · Fire Effects Information System: Ambrosia psilostachya (ranked first; Lady Bird Johnson Wildflower Center, Minnesota Wildflowers differ) · Source botanical description; original units and scope retained
- Life cycle · “Perennial” · Minnesota Wildflowers
- Light · “Partial shade; Full sun (documented habitat)” · Weakley, Flora of the Southeastern United States (2025), Carolinas & Georgia edition · Carolinas and Georgia
- Soil · “Dry; Moist (documented habitat)” · Weakley, Flora of the Southeastern United States (2025), Carolinas & Georgia edition · Carolinas and Georgia
Also known as
Ambrosia psilostachya and Ambrosia rugelii
Conservation status
| Florida rank | SNR |
|---|---|
| Global rank | G5 |
| FL status | Not verified |
| Federal status | Not verified |
In your garden
Will it fit your yard?
Check this plant against your county, sun and soil moisture. Conditions are checked in your browser.
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Sources
- Atlas of Florida Plants
- USDA PLANTS
- Vascular Plants of North Carolina (NC Natural Heritage Program)
- Weakley, Flora of the Southeastern United States (2025)
- Shropshire & Tallamy 2025, Lepidoptera of North America north of Mexico, ZooKeys 1261 (ODbL)
- Noori, Seltmann & Orr 2026, A curated and integrated dataset for exploring global bee-plant interactions (GloBI), Zenodo, CC BY 4.0
- Smith, Bachelder, Russell, Morales, Mosher & Seltmann 2024, Bee-Specialization-Modeling v0.6.1 (specialist host table compiled from J. Fowler's pollen specialist bee lists), Zenodo, CC BY 4.0
- Hurlbert, Olsen, Sawyer & Winner 2021, Avian Diet Database, Scientific Data 8: 260 (CC0)
- Narango, Tallamy & Shropshire 2020, Few keystone plant genera support the majority of Lepidoptera species, Nature Communications