Checklist of Vascular Plants Occurring at the Savanna Army Depot, Carroll and Jo Daviess Counties, Illinois

Kenneth R. Robertson, Loy R. Phillippe, Geoffey A. Levin, and Michael J. Moore
Center for Biodiversity
Illinois Natural History Survey
607 East Peabody Drive
Champaign, IL 61820 USA

Return to Ken Robertson's homepage

Click here for a temporary link to a DRAFT copy of the text for the final report

Genera beginning with A - D are given below.

Go to E - P

Go to Q - Z

In 1917, at the height of World War I, the United States Army was searching for remote, sparsely populated sites to test and store munitions. A huge expanse of sand near the Mississippi River in northwestern Illinois (Carroll and Jo Daviess counties) fit the bill and the Savanna Army Depot was established. Prior to the Army's occupation, this area, known locally as "The Prairie," was studied and observed by Dr. Henry Allan Gleason in 1908. Now, 80 years later, the Depot is being decommissioned. The Illinois Department of Natural Resources, together with various federal agencies, is gathering data to help plan the Depot's future. A team of botanists from the Illinois Natural History Survey's Center for Biodiversity is responsible for evaluating the natural communities and surveying the plants that exist at the Depot.

The Army probably did not recognize the tremendous biological significance of the Depot when it was established, but its extensive sands are very unusual in Illinois. Previous DNR-sponsored surveys of the Depot had located 11 threatened or endangered plant species. With increased access to the base, we discovered one additional state endangered species and many previously unknown populations of the others. We also found at least one plant previously unknown from Illinois that should be a candidate for threatened or endangered status.

Many of the Depot's rare plants are western species that reach their eastern limits on sandy habitats in western Illinois. Two of these, Mirabilis hirsuta (hairy umbrella wort) and Opuntia fragilis (fragile prickly pear), are known in Illinois only in Jo Daviess County, and the latter is known only from the Savanna Army Depot. Others, like Polanisia jamesii (James' clammyweed) and Carex tonsa (shaved sedge) have their largest Illinois populations on the Depot. Some of the Depot's animals show a similar pattern. For example, the only population of Lepus townsendii (white-tailed jackrabbits) in Illinois was on the Depot. Unfortunately, the jackrabbits disappeared in recent years, probably due to habitat changes and increased numbers of coyotes.

Perhaps even more significant than the individual plant species are the Depot's natural communities. Most noteworthy are its extensive prairies, savannas, and river dune forest. The savanna habitat, which consists of trees, typically oaks, scattered through a grassland, has almost disappeared from North America. Only about 6,400 acres (2,591 hectares) of tallgrass savanna remain in the United States, about 0.02% of the presettlement total. Prairies have seen similar losses. The Depot, with about 4,500 acres (1,822 hectares) of savanna and prairie, has the most extensive remaining stands of these communities in the state.

The natural communities of the Depot are not pristine, however. For obvious reasons, the Army has vigorously suppressed fires, which are vital for preserving both prairie and savanna from encroaching forests. Cattle have been used to reduce grassy vegetation and therefore reduce fire intensity. Though the cattle probably have slowed forest encroachment, they have also modified the grassland and forest vegetation. We have been uniquely able to document changes in the Depot's vegetation because not long before the Army acquired the land, noted ecologist Henry Allan Gleason, then at the Natural History Survey, published a paper describing the vegetation of the major sand deposits in Illinois, including the region that became the Depot. Overall, we observed that forest cover of the depot has increased, particular in areas that formerly were savanna. In addition, the abundance of some shrubs and grasses has increased, whereas other late successional grasses and forbs that are probably dependent on periodic fires have decreased in abundance.

Still, much of the Savanna Army Depot remains in vegetation that with proper management could recover significantly. Nowhere else in Illinois can one look across a landscape so extensively covered with prairie and savanna. As decisions are being made for the Depot's future, our research provides useful information will help preserve this remarkable remnant of our state's natural heritage.

A total of 617 taxa (species, subspecies, varieties, and forms) were found during 1996. Gleason (1910) recorded several other plants that we did not observe in 1996, including: Smilacina racemosa, Smilax ecirrhata, Petalostemum candidum, Asclepias exaltata, Scutellaria parvula / S. leonardii, Liatris cylindracea, Solidago missouriensis, and Parthenium integrifolium. Of the total of 617 taxa, 480 are native species, 3 are questionably native, and 134 are introduced.

Below is an annotated List of Vascular Plants at the Savanna Army Depot. Arranged alphabetically by scientific name. This list includes only species we observed during 1996, except for Polygala verticillata, which was collected in 1993 and Orobanche fasciculata (Orobanchaceae), which was last collected at the Depot in 1908 although suitable habitat is still extant. Under "Scientific Names", the authorities are omitted for brevity; they are included on the voucher specimens cited in Table 2. Under "E/T", E = State Endangered, T = State Threatened, FCC = former Federal Candidate Category 2, ND = Newly Discovered in Illinois and likely to qualify for listing as a state endangered species.

Scientific Name	Common Name	Family	Native or Introduced	Frequency and Habitat	E/T
Acalypha rhomboidea	Three-seeded Mercury	Euphorbiaceae	native	Occasional in sand forest and in wet-mesic floodplain forest	--
Acer negundo	Boxelder	Aceraceae	native	Occasional in sand forest, sand savanna, pastureland, and wet-mesic floodplain forest; infrequent in sand prairie	--
Acer saccharinum	Silver maple	Aceraceae	native	Abundant in wet-mesic floodplain forest	--
Acer saccharum	Sugar Maple	Aceraceae	native	Occasional in sand forest	--
Achillea millefolium	Yarrow	Asteraceae	introduced	Frequent in sand prairie and sand savanna; occasional in pastureland	--
Adiantum pedatum	Maidenhair Fern	Adiantaceae	native	Infrequent in sand forest	--
Agalinis tenuifolia	Common Agalinis	Scrophulariaceae	native	Infrequent in wet-mesic floodplain forest	--
Agastache nepetoides	Yellow Giant Hyssop	Lamiaceae	native	Occasional in sand savanna	--
Agrimonia gryposepala	Tall Agrimony	Rosaceae	native	Occasional in sand forest and sand savanna	--
Agrimonia pubescens	Soft Agrimony	Rosaceae	native	Occasional in sand forest	--
Agropyron repens f. aristatum	Quack Grass	Poaceae	introduced	Occasional in sand prairie	--
Agropyron repens f. repens	Quack Grass	Poaceae	introduced	Occasional in sand prairie	--
Agropyron smithii	Western Wheat Grass	Poaceae	introduced	Occasional in developed land, sand prairie and sand savanna	--
Agropyron subsecundum	Bearded Wheat Grass	Poaceae	native	Infrequent in sand savanna	E
Agrostis gigantea	Redtop	Poaceae	introduced	Infrequent in developed land and sand prairie	--
Agrostis hyemalis	Bent Grass	Poaceae	native	Occasional in developed land, sand prairie, and sand savanna	--
Alisma plantago-aquatica var. parviflorum	Small-flowered Water Plantain	Alismataceae	native	Occasional in wet-mesic floodplain forest	--
Alliaria petiolata	Garlic Mustard	Brassicaceae	introduced	Frequent to abundant in sand forest	--
Allium canadense	Wild Onion	Liliaceae	native	Occasional in wet-mesic floodplain forest	--
Alopecurus carolinianus	Common Foxtail	Poaceae	native	Occasional in disturbed sand pond	--
Alyssum alyssoides	Pale Allysum	Brassicaceae	introduced	Occasional in developed land and sand prairie	--
Amaranthus rudis	Water Hemp	Amaranthaceae	native	Frequent in wet-mesic floodplain forest	--
Amaranthus spinosus	Spiny Amaranth	Amaranthaceae	introduced	Rare in wet-mesic floodplain forest	--
Amaranthus tuberculatus	Amaranth	Amaranthaceae	introduced	Frequent in wet-mesic floodplain forest	--
Ambrosia artemisiifolia	Common Ragweed	Asteraceae	native?	Infrequent in developed land and sand prairie	--
Ambrosia psilostachya	Western Ragweed	Asteraceae	native	Common in sand prairie
Ambrosia trifida	Giant Ragweed	Asteraceae	native	Occasional in wet-mesic floodplain forest	--
Ammannia coccinea	Tooth-cup	Lythraceae	native	Occasional in wet-mesic floodplain forest	--
Amorpha canescens	Leadplant	Fabaceae	native	Occasional in sand prairie	--
Amorpha fruticosa	False Indigo	Fabaceae	native	Occasional in wet-mesic bottomland forest	--
Amphicarpa bracteata	Hog-peanut	Fabaceae	native	Occasional in wet-mesic floodplain forest; infrequent in sand forest	--
Andropogon gerardii	Big Bluestem	Poaceae	native	Occasional in sand prairie	--
Androsace occidentalis	Rock Jasmine	Primulaceae	native	Frequent in sand prairie and sand savanna	--
Anemone canadensis	Meadow Anemone	Ranunculaceae	native	Frequent in border with sand forest and wet-mesic floodplain forest	--
Anemone caroliniana	Carolina Anemone	Ranunculaceae	native	Infrequent in sand prairie	--
Anemone cylindrica	Thimbleweed	Ranunculaceae	native	Occasional in sand forest	--
Anemone quinquefolia	Wood Anemone	Ranunculaceae	native	Infrequent in sand forest	--
Anemone virginiana	Tall Anemone	Ranunculaceae	native	Occasional in wet-mesic floodplain forest	--
Antennaria neglecta	Cat's Foot	Asteraceae	native	Occasional in sand prairie and sand savanna	--
Antennaria plantaginifolia	Pussy Toes	Asteraceae	native	Infrequent in sand savanna	--
Apios americana	Common Ground-nut	Fabaceae	native	Infrequent in wet-mesic floodplain forest	--
Apocynum sibiricum	Creeping Dogbane	Apocynaceae	native	Infrequent in wet-mesic floodplain forest	--
Aquilegia canadensis	Wild Columbine	Ranunculaceae	native	Occasional in sand forest	--
Arabis canadensis	Sicklepod	Brassicaceae	native	Infrequent in sand forest	--
Arabis glabra	Tower Mustard	Brassicaceae	native	Rare in sand prairie	--
Arabis lyrata	Sand Cress	Brassicaceae	native	Common in sand prairie and sand savanna	--
Arabis x divaricarpa	Purple Rock Cress	Brassicaceae	native	Infrequent in sand prairie	ND
Aralia nudicaulis	Wild Sarsaparilla	Araliaceae	native	Infrequent in sand forest	--
Arctium lappa	Great Burdock	Asteraceae	introduced	Infrequent in sand savanna	--
Arctium minus	Common Burdock	Asteraceae	introduced	Occasional in disturbed sand savanna	--
Arenaria serpyllifolia	Thyme-leaved Sandwort	Caryophyllaceae	introduced	Frequent in developed land and occasional in sand prairie	--
Arisaema dracontium	Green Dragon	Araceae	native	Infrequent in wet-mesic floodplain forest	--
Arisaema triphyllum	Jack-in-the-Pulpit	Araceae	native	Infrequent in sand forest	--
Aristida basiramea	Forktip Three-awn Grass	Poaceae	native	Frequent in sand prairie and sand savanna	--
Aristida oligantha	Prairie Three-awn Grass	Poaceae	native	Infrequent in sand prairie and successional field	--
Aristida tuberculosa	Beach Three-awn Grass	Poaceae	native	Frequent in sand prairie and sand savana; Infrequent in sand forest	--
Artemisia campestris	Wormwood	Asteraceae	native	Occasional in sand forest, sand prairie, and sand savanna	--
Artemisia ludoviciana	White Sage	Asteraceae	native	Occasional in sand prairie and sand savanna	--
Asclepias amplexicaulis	Sand Milkweed	Asclepiadaceae	native	infrequent in sand prairie	--
Asclepias incarnata	Swamp Milkweed	Asclepiadaceae	native	Infrequent in wet-mesic floodplain forest	--
Asclepias syriaca	Common Milkweed	Asclepiadaceae	native	Infrequent in successional field	--
Asclepias tuberosa	Butterflyweed	Asclepiadaceae	native	Rare in sand savanna	--
Asclepias verticillata	Horsetail Milkweed	Asclepiadaceae	native	Frequent in sand prairie; occasional in sand savanna; infrequent in pastureland	--
Asclepias viridiflora	Tall Green Milkweed	Asclepiadaceae	native	Occasional in sand prairie and sand savanna	--
Asparagus officinalis	Asparagus	Liliaceae	introduced	Occasional in sand savanna	--
Asplenium platyneuron	Ebony Spleenwort	Aspleniaceae	native	Infrequent in sand forest	--
Aster cordifolius	Heart-leaved Aster	Asteraceae	native	Infrequent in sand forest	--
Aster ericoides	White Prairie Aster	Asteraceae	native	Occasional in sand prairie	--
Aster lanceolatus	Panicled Aster	Asteraceae	native	Frequent in wet-mesic floodplain forest	--
Aster lateriflorus	Starved Aster	Asteraceae	native	Occasional in wet-mesic floodplain forest	--
Aster linariifolius	Flax-leaved Aster	Asteraceae	native	Occasional in sand forest, sand prairie, and sand savana	--
Aster oblongifolius	Aromatic Aster	Asteraceae	native	Infrequent in sand forest and sand prairie	--
Aster ontarionis	Ontario Aster	Asteraceae	native	Frequent in wet-mesic floodplain forest	--
Aster oolentangiensis	Sky Blue Aster	Asteraceae	native	Rare in sand savanna	--
Aster pilosus	Hairy Aster	Asteraceae	native	Common in sand prairie and sand savanna
Aster prenanthoides	Crooked-stemmed Aster	Asteraceae	native	Occasional in wet-mesic floodplain forest	--
Aster puniceus	Purple-stemmed Aster	Asteraceae	native	Occasional in wet-mesic floodplain forest	--
Aster sericeus	Western Silvery Aster	Asteraceae	native	Infrequent in sand prairie	--
Athyrium filix-femina var. angustum	Lady Fern	Dryopteridaceae	native	Infrequent in sand forest	--
Bacopa rotundifolia	Water Hyssop	Scrophulariaceae	native	Rare in natural sand pond	--
Barbarea vulgaris	Yellow Rocket	Brassicaceae	introduced	Infrequent in developed land	--
Berberis thunbergii	Japanese Barberry	Berberidaceae	introduced	Infrequent in sand forest and sand savanna	--
Berteroa incana	Hoary Alyssum	Brassicaceae	introduced	Occasional in developed land, sand prairie and sand savanna	--
Besseya bullii	Kitten Tails	Scrophulariaceae	native	Occasional in sand forest, sand prairie, and sand savanna	T
Betula nigra	River Birch	Betulaceae	native	Occasional in wet-mesic floodplain forest	--
Bidens cernua	Bur-marigold	Asteraceae	native	Occasional in wet-mesic floodplain forest	--
Bidens tripartita	Beggar-ticks	Asteraceae	introduced	Occasional in wet-mesic floodplain forest	--
Bidens vulgata	Tall Beggar-ticks	Asteraceae	native	Occasional in wet-mesic floodplain forest	--
Boehmeria cylindrica	False Nettle	Urticaceae	native	Occasional in wet-mesic bottomland forest	--
Botrychium dissectum	Dissected Grapefern	Ophioglossaceae	native	Occasional in wet-mesic floodplain forest	--
Botrychium virginianum	Rattlesnake Fern	Ophioglossaceae	native	Infrequent in wet-mesic floodplain forest	--
Bouteloua curtipendula	Side-oats Grama Grass	Poaceae	native	Occasional in sand prairie	--
Bouteloua gracilis	Blue Grama-grass	Poaceae	native	Rare in sand prairie	ND
Bouteloua hirsuta	Hairy Grama Grass	Poaceae	native	Frequent in sand prairie	--
Brassica nigra	Black Mustard	Brassicaceae	introduced	Infrequent in developed land
Brickellia eupatorioides	False Boneset	Asteraceae	native	Infrequent in sand prairie	--
Bromus inermis	Awnless Brome	Poaceae	introduced	Occasional in developed land and sand prairie	--
Bromus kalmii	Kalm's Brome	Poaceae	native	Infrequent in wet-mesic floodplain forest	--
Bromus racemosus	Smooth Chess	Poaceae	introduced	Occasional to frequent in sand prairie and sand savanna	--
Bromus tectorum	Downy Chess	Poaceae	introduced	Frequent in developed land and sand prairie and sand savanna	--
Bulbostylis capillaris	Autumn Sedge	Cyperaceae	native	Occasional in sand prairie	--
Calamovilfa longifolia	Sand-reed	Poaceae	native	Rare in sand savanna	--
Callirhoë triangulata	Poppy Mallow	Malvaceae	native	Occasional in sand prairie and sand savanna	--
Caltha palustris	Marsh Marigold	Ranunculaceae	native	Rare in wet-mesic floodplain forest	--
Calystegia sepium	American Bindweed	Convolvulaceae	native	Infrequent in developed land along edge of wet-mesic floodplain forest	--
Campanula americana	American Bellflower	Campanulaceae	native	Occasional in wet-mesic bottomland forest	--
Cannabis sativa	Marijuana	Cannabinaceae	introduced	Occasional in sand savanna	--
Capsella bursa-pastoris	Shepard's Purse	Brassicaceae	introduced	Occasional in developed land	--
Cardamine bulbosa	Spring Cress	Brassicaceae	native	Occasional in wet-mesic floodplain forest	--
Cardamine hirsuta	Spring Cress	Brassicaceae	introduced	Infrequent in wet-mesic floodplain forest	--
Cardamine parviflora var. arenicola	Small-flowered Bitter Cress	Brassicaceae	native	Occasional in sand savanna	--
Cardamine pensylvanica	Pennsylvania Bitter-cress	Brassicaceae	native	Occasional in wet-mesic floodplain forest	--
Carduus nutans	Musk Thistle	Asteraceae	introduced	Infrequent in successional field	--
Carex annectens	Large Yellow Fox Sedge	Cyperaceae	native	Occasional in sand prairie, edge of ponds, and wet-mesic floodplain forest	--
Carex bicknellii	Copper-shouldered Oval Sedge	Cyperaceae	native	Frequent in sand prairie and sand savanna	--
Carex blanda	Common Wood Sedge	Cyperaceae	native	Occasional in sand forest	--
Carex brevior	Plains Oval Sedge	Cyperaceae	native	Frequent in sand prairie	--
Carex conjuncta	Green-headed Fox Sedge	Cyperaceae	native	Occasional in wet-mesic floodplain forest	--
Carex cristatella	Crested Oval Sedge	Cyperaceae	native	Occasional in wet-mesic bottomland forest	--
Carex duriuscula	Sedge	Cyperaceae	native	Rare in developed land	--
Carex frankii	Bristly Cattail Sedge	Cyperaceae	native	Occasional in wet-mesic bottomland forest and along streams	--
Carex gravida	Long-awned Bracted Sedge	Cyperaceae	native	Occasional in developed land and sand prairie	--
Carex grayi	Common Bur Sedge	Cyperaceae	native	Occasional in wet mesic floodplain forest	--
Carex grisea	Wood Gray Sedge	Cyperaceae	native	Occasional in wet-mesic floodplain forest	--
Carex hirtifolia	Hairy Wood Sedge	Cyperaceae	native	Occasional in sand forest	--
Carex hystericina	Porcupine Sedge	Cyperaceae	native	Occasional in wet-mesic floodplain forest	--
Carex laeviconica	Long-toothed Lake Sedge	Cyperaceae	native	Rare along edge of ox-bow lake	--
Carex lupulina	Common Hop Sedge	Cyperaceae	native	Occasional in edge of pond and wet-mesic floodplain forest	--
Carex meadii	Mead's Stiff Sedge	Cyperaceae	native	Infrequent in sand prairie and sand savanna	--
Carex molesta	Field Oval Sedge	Cyperaceae	native	Occasional in sand prairie	--
Carex muhlenbergii	Sand Bracted Sedge	Cyperaceae	native	Frequent in sand prairie and sand savanna; occasional in sand forest	--
Carex pensylvanica	Common Oak Sedge	Cyperaceae	native	Occasional to frequent in sand forest, sand prairie and sand savanna	--
Carex rosea	Curly-styled Wood Sedge	Cyperaceae	native	Occasional in sand forest	--
Carex scoparia var. scoparia	Lance-fruited Oval Sedge	Cyperaceae	native	Occasional in sand savanna	--
Carex stipata	Common Fox Sedge	Cyperaceae	native	Occasional in sand forest	--
Carex stricta	Common Tussock Sedge	Cyperaceae	native	Occasional in wet-mesic floodplain forest	--
Carex tonsa	Shaved Sedge	Cyperaceae	native	Frequent in sand prairie and sand savanna; occasional in sand forest	E
Carex tribuloides	Awl-fruited Oval Sedge	Cyperaceae	native	Occasional in edge of pond	--
Carex typhina	Common Cattail Sedge	Cyperaceae	native	Infrequent in sand forest	--
Carex vulpinoidea	Brown Fox Sedge	Cyperaceae	native	Occasional in developed land	--
Carya cordiformis	Bitternut Hickory	Juglandaceae	native	Occasional in sand forest and wet-mesic floodplain forest	--
Carya ovata	Shagbark Hickory	Juglandaceae	native	Occasional in sand forest	--
Carya tomentosa	Mockernut Hickory	Juglandaceae	native	Occasional in sand forest	--
Catalpa speciosa	Northern Catalpa	Bignoniaceae	introduced	Infrequent in wet-mesic floodplain forest	--
Ceanothus americanus	New Jersey Tea	Rhamnaceae	native	Infrequent in sand savanna	--
Ceanothus herbaceus (C. ovatus)	Redroot	Rhamnaceae	native	Occasional to frequent in sand prairie	E
Celastrus scandens	Bittersweet	Celastraceae	native	Occasional in sand forest	--
Celtis occidentalis	Hackberry	Ulmaceae	native	Occasional in sand forest and sand savanna Infrequent in sand prairie	--
Cenchrus longispinus	Sand Bur	Poaceae	native	Frequent in developed land and occasional in sand prairie	--
Centaurea maculosa	Spotted Knapweed	Asteraceae	introduced	Occasional in successional field	--
Cephalanthus occidentalis	Buttonbush	Rubiaceae	native	Occasional in wet-mesic bottomland forest	--
Cerastium brachypodum	Mouse-eared Chickweed	Caryophyllaceae	introduced	Occasional in sand prairie and developed land	--
Cerastium vulgatum	Common Mouse-eared Chickweed	Caryophyllaceae	introduced	Occasional in developed land and sand prairie and sand savanna	--
Ceratophyllum demersum	Hornwort	Ceratophyllaceae	native	Occasional as aquatic in Mississippi River	--
Chaenorrhinum minus	Dwarf Snapdragon	Scrophulariaceae	introduced	Occasional in developed land	--
Chamaecrista fasciculata	Partridge Pea	Fabaceae	native	Occasional in sand prairie and sand savanna	--
Chamaesyce geyeri	Geyer's Spurge	Euphorbiaceae	native	Frequent in sand prairie and sand savanna	--
Chamaesyce maculata	Spotted Spurge	Euphorbiaceae	native	Occasional in developed land	--
Chamaesyce nutans	Eyebane	Euphorbiaceae	native	Occasional in developed land	--
Chenopodium ambrosioides	Mexican Tea	Chenopodiaceae	introduced	Occasional in developed land and successional field	--
Chenopodium gigantospermum	Maple-leaved Goose Foot	Chenopodiaceae	native	Infrequent in sand savanna	--
Chenopodium pratericola	Goosefoot	Chenopodiaceae	native	Occasional in sand prairie, sand savanna and sand forest; infrequent in developed land	--
Chenopodium simplex	Maple-leaved Goosefoot	Chenopodiaceae	native	Occasional in sand forest and sand savanna	--
Chloris verticillata	Windmill Grass	Poaceae	introduced	Occasional in developed land and successional field	--
Cicuta maculata	Water Hemlock	Apiaceae	native	Infrequent in wet-mesic floodplain forest	--
Cinna arundinacea	Common Woodreeed	Poaceae	native	Infrequent in wet-mesic floodplain forest	--
Circaea lutetiana subsp. canadensis	Enchanter's Nightshade	Onagraceae	native	Occasional in sand forest	--
Cirsium arvense	Canada Thistle	Asteraceae	introduced	Infrequent in pastureland	--
Cirsium discolor	Field Thistle	Asteraceae	native	Infrequent in wet-mesic bottomland forest	--
Cirsium vulgare	Bull Thistle	Asteraceae	introduced	Infrequent in sand savanna	--
Claytonia virginica	Spring Beauty	Portulacaceae	native	Frequent in sand forest	--
Clematis virginiana	Virgin's Bower	Ranunculaceae	native	Infrequent in wet-mesic floodplain forest	--
Comandra umbellata	False Toadflax	Santalaceae	native	Occasional in sand prairie and sand savanna	--
Commelina erecta	Erect Day-flower	Commelinaceae	native	Occasional in sand forest and sand savanna	--
Conium maculatum	Poison Hemlock	Apiaceae	introduced	Infrequent in wet-mesic floodplain forest	--
Convolvulus arvensis	Field Bindweed	Convolvulaceae	introduced	Occasional in sand prairie	--
Conyza canadensis	Horseweed	Asteraceae	native	Frequent in successional field, infrequent in sand savanna	--
Coreopsis palmata	Prairie Coreopsis	Asteraceae	native	Infrequent in sand prairie and sand savanna	--
Cornus drummondii	Rough-leaved Dogwood	Cornaceae	native	Occasional in sand forest and sand savanna	--
Cornus racemosa	Gray Dogwood	Cornaceae	native	Frequent in sand forest, sand savanna, and wet-mesic floodplain forest	--
Coronilla varia	Crown Vetch	Fabaceae	introduced	Occasional in developed land, sand prairie, and sand savanna	--
Corydalis micrantha	Slender Corydalis	Fumariaceae	native	Occasional in sand forest and sand savanna	--
Corylus americana	Hazelnut	Betulaceae	native	Infrequent in sand forest	--
Crataegus calpodendron	Hawthorn	Rosaceae	native	Occasional in sand forest, sand prairie, and sand savanna	--
Crepis tectorum	Hawksbeard	Asteraceae	introduced	Infrequent in sand prairie and successional field	--
Crotalaria sagittalis	Rattlebox	Fabaceae	native	Occasional in sand prairie and sand savanna	--
Croton glandulosus var. septentrionalis	Sand Croton	Euphorbiaceae	native?	Occasional in sand prairie and sand savanna	--
Cryptotaenia canadensis	Honewort	Apiaceae	native	Abundant in wet-mesic floodplain forest; occasional in sand forest	--
Cycloloma atriplicifolium	Winged Pigweed	Chenopodiaceae	native	Occasional in developed land, sand forest, sand prairie, and sand savanna
Cynoglossum officinale	Common Hound's-tongue	Boraginaceae	introduced	Occasiona in developed land and sand savanna	--
Cyperus aristatus	Flatsedge	Cyperaceae	native	Occasional in wet-mesic floodplain forest	--
Cyperus erythrorhizos	Redroot Flatsedge	Cyperaceae	native	Occasional in wet-mesic bottomland forest	--
Cyperus esculentus var. esculentus	Yellow Nutsedge	Cyperaceae	native	Occasional in wet-mesic bottomland forest	--
Cyperus filiculmis var. filiculmis	Slender Sand Sedge	Cyperaceae	native	Frequent in sand prairie and sand savnaan; occasional in sand forest	--
Cyperus filiculmis var. macilentus	Slender Sand Sedge	Cyperaceae	native	Occasional in sand forest; frequent in sand prairie and sand savanna	--
Cyperus grayioides	Gray's Umbrella Sedge	Cyperaceae	native	Occasional in blowouts of sand prairie and sand savanna	T
Cyperus odoratus	Flatsedge	Cyperaceae	native	Occasional in wet-mesic floodplain forest	--
Cyperus schweinitzii	Rough Sand Sedge	Cyperaceae	native	Occasional in sand forest; frequent in sand prairie and sand savanna	--
Cystopteris protrusa	Fragile Fern	Dryopteridaceae	native	Occasional in sand forest	--
Dactylis glomerata	Orchard Grass	Poaceae	introduced	Occasional in developed land	--
Daucus carota	Queen Anne's Lace	Apiaceae	introduced	Occasional in successional field	--
Descurainia pinnata subsp. brachycarpa	Tansy Mustard	Brassicaceae	native	Infrequent in sand prairie, sand savanna, and developed land	--
Desmodium canadense	Canadian Tick-trefoil	Fabaceae	native	Infrequent in opening in wet-mesic floodplain forest	--
Desmodium glutinosum	Pointed Tick Trefoil	Fabaceae	native	Occasional in sand forest	--
Desmodium illinoense	Illinois Tick Trefoil	Fabaceae	native	Infrequent in sand prairie	--
Dianthus armeria	Deptford Pink	Caryophyllaceae	introduced	Occasional in sand prairie and sand savanna	--
Dicentra cucullaria	Dutchman's Breeches	Fumariaceae	native	Infrequent in sand forest	--
Digitaria sanguinalis	Hairy Crabgrass	Poaceae	introduced	Occasional in developed land	--
Diodia teres	Rough Buttonweed	Rubiaceae	native?	Frequent in sand prairie and sand savanna and occasional in sand forest	--
Draba nemorosa var. leiocarpa	Whitlow Grass	Brassicaceae	native	Rare in sand prairie	ND
Draba reptans	Common Whitlow Grass	Brassicaceae	native	Frequent in sand prairie and sand savanna	--
Draba verna	Vernal Whitlow Grass	Brassicaceae	introduced	Occasional in developed land	--
Dryopteris carthusiana	Spinulose Woodfern	Dryopteridaceae	native	Occasional in sand forest