Source: Checklist of Endangered and Threatened Animals and Plants of Illinois
Illinois Endangered Species Protection Board, February 22, 2011
* = Federally Threatened ** = Federally Endangered
| Agalinus skinneriana | Pale False Foxglove |
| Amelanchier interior | Shadbush |
| Aster furcatus | Forked Aster |
| Berchemia scandens | Supple-Jack |
| Besseya bullii | Kitten Tails |
| Boltonia decurrens* | Decurrent False Aster |
| Botrychium biternatum | Southern Grape Fern |
| Buchnera americana | Bluehearts |
| Cakile edentula | Sea Rocket |
| Chamaedaphne calyculata | Leatherleaf |
| Cimicifuga rubifolia | Black Cohosh |
| Cirsium pitcheri* | Pitcher’s (Dune) Thistle |
| Corallorhiza maculata | Spotted Coral-root Orchid |
| Cyperus grayioides | Umbrella Sedge |
| Cyperus lancastriensis | Galingale |
| Cypripedium candidum | White Lady’s Slipper |
| Delphinium carolinianum | Wild Blue Larkspur |
| Dodecatheon frenchii | French’s Shootingstar |
| Drosera intermedia | Narrow-leaved Sundew |
| Epilobium strictum | Downy Willow Herb |
| Equisetum pratense | Meadow Horsetail |
| Helianthus angustifolius | Narrow-leaved Sunflower |
| Hymenopappus scabiosaeus | Old Plainsman |
| Juncus alpinus | Richardson’s Rush |
| Lathyrus ochroleucus | Pale Vetchling |
| Lechea intermedia | Pinweed |
| Liatris scariosa var. nieuwlandii | Blazing Star |
| Matelea obliqua | Climbing Milkweed |
| Melanthium virginicum | Bunchflower |
| Melothria pendula | Squirting Cucumber |
| Menyanthes trifoliata | Buckbean |
| Minuartia patula | Slender Sandwort |
| Oenothera perennis | Small Sundrops |
| Orobanche ludoviciana | Broomrape |
| Platanthera flava var.herbiola | Tubercled Orchid |
| Ranunculus rhomboideus | Prairie Buttercup |
| Rudbeckia missouriensis | Missouri Orange Coneflower |
| Salvia azurea subsp. empitcheri | Blue Sage |
| Schoenoplectus hallii | Hall’s Bulrush |
| Scirpus polyphyllus | Bulrush |
| Sedum telephioides | American Orpine |
| Sisyrinchium atlanticum | Eastern Blue-eyed Grass |
| Solidago sciaphila | Cliff Goldenrod |
| Styrax americana | Storax |
| Sullivantia sullivantii | Sullivantia |
| Talinum parviflorum | Small Flower-of-an-hour |
| Tofieldia glutinosa | False Asphodel |
| Tomanthera auriculata | Ear-leafed Foxglove |
| Tradescantia bracteata | Prairie Spiderwort |
| Trifolium reflexum | Buffalo Clover |
| Triglochin maritima | Common Bog Arrowgrass |
| Triglochin palustris | Slender Bog Arrowgrass |
| Urtica chamaedryoides | Nettle |
| Utricularia intermedia | Flat-leaved Bladderwort |
| Veronica scutellata | Marsh Speedwell |
| Viola conspersa | Dog Violet |