Olney's Threesquare
Schoenoplectus americanus
Found in tidal freshwater to brackish marshes. Weakley, Flora of the Southeastern United States (2025), South Central edition What its natural habitat tells you
Native to Alabama. How scores work Is it native here?
Profile 76%
- Height
- It has erect, sharply triangular and deeply concave-sided culms growing up to 5 feet in height [10,21].
- Light
- Partial shade, Full sun
- Soil moisture
- Wet to standing water
No photograph yet. Looking for an old drawing…
At a glance
- Life cycle
- Perennial
- Bloom
- May to June
- Fruiting season
- June to September
Not yet recorded · Spread · Leaves
Recorded in 3 Alabama counties.
Natural habitats
Places it grows wild. Not a planting requirement. Each habitat page lists the plants and wildlife also found there.
Coastal marshes flooded by salty or brackish tides.
Also found with this plant
Wildlife whose habitat models include habitats this plant grows in, in Alabama. Shared habitat, not food. 199 animals.
- Sharp-shinned HawkAccipiter striatus
- Song SparrowMelospiza melodia
- SoraPorzana carolina
- Spotted SandpiperActitis macularius
- Tree SwallowTachycineta bicolor
- Turkey VultureCathartes aura
- White-throated SparrowZonotrichia albicollis
- Yellow-breasted ChatIcteria virens
- Yellow-crowned Night-heronNyctanassa violacea
- Acadian FlycatcherEmpidonax virescens
- Alder FlycatcherEmpidonax alnorum
- American AvocetRecurvirostra americana
- American BitternBotaurus lentiginosus
- American GoldfinchCarduelis tristis
- American KestrelFalco sparverius
- American OystercatcherHaematopus palliatus
- American PipitAnthus rubescens
- American RedstartSetophaga ruticilla
- American RobinTurdus migratorius
- American White PelicanPelecanus erythrorhynchos
- American WigeonAnas americana
- American WoodcockScolopax minor
- AnhingaAnhinga anhinga
- Bald EagleHaliaeetus leucocephalus
Who uses this plant?
11CaterpillarsGenus host records with ranges including AL
Genus host records with ranges including AL · Scirpus
- Bactra furfuranaRush Bactra
- Bactra verutanaJavelin Moth
- Euphyes dionDion Skipper, Sedge Skipper
- Globia oblongaOblong Sedge Borer Moth, Large Noagria
- Ledaea perditalisLost Owlet, 3-Stripe Cephalanthus caterpillar, Buttonbush Owlet
- Meropleon diversicolorMulticolored Sedgeminer
- Neonympha areolataGeorgia Satyr, Helicta Satyr
- Bactra maiorina
- Cosmopterix attenuatella
- Cosmopterix ebriola
Show all 11
- Cosmopterix scirpicola
27BirdsRecorded genus food-resource interactions; not a state feeding claim
Recorded genus food-resource interactions; not a state feeding claim · Scirpus
- Agelaius phoeniceusRed-winged Blackbird
- Anas platyrhynchosMallard
- Anthus rubescensAmerican Pipit
- Aythya affinisLesser Scaup
- Aythya americanaRedhead
- Aythya collarisRing-necked Duck
- Aythya marilaGreater Scaup
- Aythya valisineriaCanvasback
- Bucephala clangulaCommon Goldeneye
- Bucephala islandicaBarrow's Goldeneye
Show all 27
- Calcarius lapponicusLapland Longspur
- Calcarius pictusSmith's Longspur
- Cygnus buccinatorTrumpeter Swan
- Cygnus columbianusTundra Swan
- Fulica americanaAmerican Coot
- Gallinula galeataCommon Gallinule
- Loxia curvirostraRed Crossbill
- Mareca americanaAmerican Wigeon
- Mareca streperaGadwall
- Molothrus aterBrown-headed Cowbird
- Oxyura jamaicensisRuddy Duck
- Plectrophenax nivalisSnow Bunting
- Porzana carolinaSora
- Rallus limicolaVirginia Rail
- Spatula cyanopteraCinnamon Teal
- Spizelloides arboreaAmerican Tree Sparrow
- Sturnus vulgarisEuropean Starling
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
Plant details
- Family
- Cyperaceae
- Flower color
- Yellow or brown
- Fruit begins
- June
- Fruit ends
- September
Safety has not been reviewed for this plant; check toxicity and thorns before planting.
Growing sources and scope
- Bloom · “Late May to June” · Weakley, Flora of the Southeastern United States (2025), Carolinas & Georgia edition · Carolinas and Georgia
- Flower color · “Yellow or brown” · Lady Bird Johnson Wildflower Center
- Fruit begins · “June” · Weakley, Flora of the Southeastern United States (2025), Carolinas & Georgia edition · Carolinas and Georgia
- Fruit ends · “September” · Weakley, Flora of the Southeastern United States (2025), Carolinas & Georgia edition · Carolinas and Georgia
- Height · “It has erect, sharply triangular and deeply concave-sided culms growing up to 5 feet in height (1.5 m) [10,21].” · Fire Effects Information System: Schoenoplectus americanus (ranked first; Lady Bird Johnson Wildflower Center differs) · Source botanical description; original units and scope retained
- Life cycle · “Perennial” · Lady Bird Johnson Wildflower Center
- Light · “Partial shade; Full sun (documented habitat)” · Weakley, Flora of the Southeastern United States (2025), Carolinas & Georgia edition · Carolinas and Georgia
- Soil · “Water; Wet (documented habitat)” · Weakley, Flora of the Southeastern United States (2025), Carolinas & Georgia edition · Carolinas and Georgia
Also known as
Scirpus olneyi Gray; bulrush
Conservation status
| Alabama rank | SNR |
|---|---|
| Global rank | G5 |
| AL status | Not verified |
| Federal status | Not verified |
Will it fit your yard?
Check this plant against your county, sun and soil moisture. Conditions are checked in your browser.
Sources
- Alabama Plant Atlas
- 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

























