Plant Science — Conservation
Invasive Plants in the Chicago Region
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Plants with a dash under the "alternatives" column are not commonly used ornamentally. You can find more information on alternatives at Illinois' Best Plants or www.bestplants.org.
| HERBACEOUS PLANTS | |||
| Species | Common Name | Status | Alternatives |
| Aegopodium podagraria | Goutweed | R | Asarum (wild ginger), Epimedium spp. (barrenwort), Glandularia canadensis (mock rose vervain), Hosta (hosta) |
| Alliaria petiolata | Garlic mustard | R | ______ |
| Arctium minus | Lesser burdock | R | ______ |
| Carduus nutans | Nodding plumeless thistle | R | Echinacea spp. (coneflower), Silphium spp. (rosinweed, prairie dock, compass plant) |
| Centaurea maculosa | Spotted knapweed | R | Echinacea spp. (coneflower), Silphium spp. (rosinweed, prairie dock, compass plant) |
| Cirsium arvense | Canada thistle | R | Echinacea spp. (coneflower), Silphium spp. (rosinweed, prairie dock, compass plant) |
| Cirsium palustre | Marsh plume thistle | R | (see C. arvense) |
| Cirsium vulgare | Bull thistle | R | (see C. arvense) |
| Conium maculatum | Poison hemlock | R | Achillea spp. (yarrow), Aruncus spp. (goatsbeard), Actaea racemosa (black cohosh), Filipendula spp. (meadowsweet) |
| Coronilla varia | Crown vetch | R | Asarum spp. (ginger), Epimedium spp. (barrenwort), Glandularia canadensis (mock rose vervain), Hosta (hosta), Viola (violet) |
| Daucus carota | Queen Anne's lace | R | Aruncus spp. (goatsbeard), Achillea spp. (yarrow) |
| Dipsacus laciniatus | Cutleaf teasel | R | Echinacea spp. (coneflower), Rudbeckia spp. (black-eyed Susan) |
| Dipsacus sylvestris | Teasel | R | (see D. laciniatus) |
| Duchesnia indica | Wild strawberry | R | Waldsteinia ternata (barren strawberry) |
| Echinops sphaerocephalus | Globe thistle | R species E cultivars |
Liatris spp. (blazing star), Monarda spp. (beebalm), Phlox spp. (phlox), Salvia spp. (sage), Thalictrum spp.(meadowrue), Veronica spp. (speedwell) |
| Epilobium hirsutum | Hairy fireweed | R | (see E. sphaerocephalus) |
| Euphorbia cyparissias | Cypress spurge | R | Origanum laevigatum (ornamental oregano), selected Sedum spp. (stonecrop) |
| Euphorbia esula | Leafy spurge | R | Aurinia saxatilis (basket-of-gold) |
| Glechoma hederacea | Ground ivy | R | Ajuga spp. (bugleweed), Ceratostigma plumbaginoides (leadwort), Plumbago auriculata (cape leadwort) |
| Gypsophila paniculata | Baby's breath | W | Boltonia asteroides (boltonia), Panicum virgatum cvs. (switch grass), |
| Hemerocallis fulva (locally invasive) | Tawny daylily | R | Hemerocallis hybrids (daylily), Lilium spp. & cvs. (lily), Papaver orientale (Oriental poppy) |
| Hesperis matronalis | Dame's rocket | R | (See E. sphaerocephalus) |
| Houttuynia cordata | Chameleon plant | W | Alchemilla mollis (lady's mantle), Asarum spp. (ginger), Chrysogonum virginianum (green and gold) |
| Hypericum perforatum | Common St. Johnswort | R | Other Hypericum spp. (St. Johnswort) |
| Iris pseudacorus | Yellow flag iris | R species E cultivars |
Iris fulva 'Lois Yellow' (copper iris), Iris virginica var. shrevii (interior blue flag iris) |
| Lespedeza cuneata | Chinese bush clover | R | Baptisia spp. (wild indigo) |
| Linaria vulgaris | Butter-and-eggs | R | Antirrhinum majus cvs. (snapdragons), Calibrachoa cvs. (million bells), Digitalis spp. (foxglove), Nemesia fruticans cvs. (nemesia) |
| Lotus corniculatus | Bird's-foot trefoil | R | ______ |
| Lysimachia nummularia | Moneywort | R | Chrysogonum virginianum (green and gold), Origanum laevigatum (ornamental oregano) |
| Lythrum salicaria | Purple loosestrife | R | Asclepias incarnata (swamp milkweed), Liatris spp. (blazing star), Physostegia virginiana 'Vivid' (obedient plant) |
| Melilotus alba | White sweet-clover | R | Baptisia spp. (wild indigo) |
| Melilotus officinalis | Yellow sweet- clover | R | Baptisia spp. (wild indigo) |
| Pastinaca sativa | Wild parsnip | R | ______ |
| Perilla frutescens | Beefsteak plant | R | Hibiscus acetosella (red leaf hibiscus), Ocimum basilicum cvs. (basil), Solenostemon scutellarioides (coleus) |
| Polygonum cuspidatum = P. japonicum | Japanese knotweed | E | Actaea racemosa (black cohosh), Aruncus dioicus (goatsbeard), Polygonatum spp. (Solomon's seal), Smilacina racemosa (false Solomon's seal), Tricyrtis spp. (toad lily) |
| Polygonum sachalinense | Giant knotweed | R | (see P. cuspidatum) |
| Portulaca oleracea | Purslane | R species E cultivars |
Aurinia saxatilis (basket-of-gold), selected Sedum spp. & cvs. (stonecrop) |
| Potentilla argentea | Silver cinquefoil | R | Chrysogonum virginianum (green and gold) |
| Rorippa sylvestris | Creeping yellow-cress | R | Aurinia saxatilis (basket-of-gold), selected Sedum ssp. & cvs. (stonecrop) |
| Rumex acetosella | Garden sorrel | R | Beta vulgaris 'Bright Lights' (Swiss chard) Solenostemon scutellarioides (coleus) |
| Saponaria officinalis | Bouncing bet | R species E cultivars |
Liatris spp. (blazing star), Monarda spp. (bee balm), Phlox spp. (phlox), Salvia spp. (sage), Thalictrum spp. (meadowrue), Veronica spp. (speedwell) |
| Sonchus arvensis | Field sow-thistle | R | Coreopsis spp. (coreopsis); Helianthus spp. (sunflower) |
| Valeriana officinalis | Common valerian | R | (See E. sphaerocephalus) |
| Verbascum thapsus | Flannel mullein | R | Digitalis spp. (foxglove) |
| Verbena bonariensis | Purpletop verbena | W | (See E. sphaerocephalus) |
| GRASSES | |||
| Species | Common Name | Status | Alternatives |
| Agropyron repens | Quack grass | R | Panicum virgatum cvs. (switch grass), Sporobolus heterolepsis (prairie dropseed) |
| Bromus inermis | Smooth brome | R | ______ |
| Festuca elatior (=F. arundinacea) | Tall fescue | R | ______ |
| Festuca pratensis | Meadow fescue | R | ______ |
| Microstegium vimineum | Japanese stilt grass | R | ______ |
| Miscanthus sacchariflorus | Amur silver grass | R | (see A. repens) |
| Miscanthus sinensis | Chinese silver grass | R var. | (see A. repens) |
| Miscanthus sinensis 'purpurascens' | Autumn Red Miscanthus, Flame Grass, Eulalia, Maiden Grass, Zebra Grass | R | ______ |
| Phalaris arundinacea | Reed canary grass | R | Spartina pectinata 'Aureomarginata' (variegated prairie cordgrass) |
| Phragmites australis | Common reed | R | Erianthus ravennae (Plume grass) |
| Setaria faberi | Japanese bristlegrass | R | ______ |
| Sorghum halapense | Johnson grass | R | ______ |
| SHRUBS | |||
| Species | Common Name | Status | Alternatives |
| Berberis thunbergii | Japanese barberry | R species E cultivars |
Physocarpus opulifolius (ninebark), Ribes odoratum (clove currant) |
| Berberis vulgaris | European barberry | R | Physocarpus opulifolius (ninebark), Ribes odoratum (clove currant) |
| Cotoneaster multiflorus | Many-flowered cotoneaster | P | Physocarpus opulifolius (ninebark), Ribes odoratum (clove currant) |
| Elaeagnus angustifolia | Russian olive | W | Aesculus parviflora (bottlebrush buckeye), Aronia melanocarpa (black chokeberry), Corylus americana (American filbert) |
| Elaeagnus umbellatus | Autumn olive | R | Aesculus parviflora (bottlebrush buckeye), Aronia melanocarpa (black chokeberry), Corylus americana (American filbert) |
| Euonymus alatus | Winged euonymus | R | Euonymus americanus (American strawberry bush), Itea virginica (Virginia sweetspire), Rhus copallina var. latifolia 'Morton' (Prairie Flame shining sumac) |
| Euonymus europeaus | European spindletree | R | Euonymus americanus (American strawberry bush), Itea virginica (Virginia sweetspire) |
| Hippophae rhamnoides | Common sea buckthorn | R | ______ |
| Ligustrum obtusifolium | Border privet | P | Physocarpus opulifolius (ninebark), Ribes odoratum (clove currant) |
| Ligustrum vulgare | Common privet | P | Physocarpus opulifolius (ninebark), Ribes odoratum (clove currant) |
| Lonicera x bella | Bell's honeysuckle | R | Amelanchier spp. & cvs. (serviceberry), Calycanthus floridus (Carolina allspice), Diervilla spp. (bush honeysuckle) |
| Lonicera japonica | Japanese honeysuckle | R | ______ |
| Lonicera maackii | Amur honeysuckle | R | Amelanchier spp. & cvs. (serviceberry), Calycanthus floridus (Carolina allspice), Diervilla spp. (bush honeysuckle) |
| Lonicera morrowii | Morrow's honeysuckle | R | Amelanchier spp. & cvs. (serviceberry), Calycanthus floridus (Carolina allspice), Diervilla spp. (bush honeysuckle) |
| Lonicera tatarica | Tatarian honeysuckle | R | Amelanchier spp. & cvs. (serviceberry), Calycanthus floridus (Carolina allspice), Diervilla spp. (bush honeysuckle) |
| Rhamnus cathartica | Common buckthorn | R | Alnus rugosa (speckled alder), Carpinus caroliniana (American hornbeam), Corylus americana (American filbert), Thuja occidentalis (American arborvitae) and Thuja plicata (giant arborvitae) |
| Rhamnus frangula | Glossy buckthorn | R | Alnus rugosa (speckled alder), Carpinus caroliniana (American hornbeam), Corylus americana (American filbert), Thuja occidentalis (American arborvitae) and Thuja plicata (giant arborvitae) |
| Rosa multiflora | Japanese rose | R | Rosa spp. & cvs. (hardy shrub roses) |
| Spiraea japonica | Japanese meadowsweet | W | Clethra spp. (summersweet), Hydrangea spp. (hydrangea), native Spiraea (spirea) |
| Syringa reticulata | Japanese tree lilac | W | Clethra spp. (summersweet), Hydrangea spp. (hydrangea) |
| Viburnum opulus | European cranberrybush viburnum | R species E cultivars |
Viburnum dentatum cvs. (arrowwood viburnum), Viburnum trilobum (American cranberrybush viburnum) |
| TREES | |||
| Species | Common Name | Status | Alternatives |
| Acer ginnala | Amur maple | P | Acer rubrum (red maple), Quercus alba (white oak) |
| Acer platanoides | Norway maple | R species E cultivars |
Acer x freemanii 'Marmo' (Marmo maple), Acer miyabei (Miyabe maple), Acer rubrum (red maple), Quercus alba (white oak) |
| Ailanthus altissima | Tree-of-heaven | R | Fraxinus spp. (ash species) |
| Alnus glutinosa | European black alder | P species E cultivars |
Celtis laevigata (sugarberry), Celtis occidentalis (common hackberry), Nyssa sylvatica (black tupelo) |
| Malus spp. (crabapple) | Crabapple | E | Crataegus spp. (hawnthorn species), Prunus serotina (black cherry) |
| Morus alba | Mulberry | P | Crataegus spp. (hawthorn species), Prunus serotina (black cherry) |
| Phellodendron amurense (except male cultivars) | Amur corktree | R | Acer rubrum (red maple), Phellodendron amurense (male cvs.), Quercus alba (white oak) |
| Populus alba | White poplar | P | Betula nigra (river birch), Catalpa speciosa (Northern catalpa), Platanus occidentalis (American sycamore) |
| Prunus mahaleb | Mahaleb cherry | P | Crataegus spp. (hawthorn species), Prunus serotina (black cherry) |
| Pyrus calleryana | Callery ornamental pear | W | Chionanthus virginicus (fringetree), Crataegus spp. (hawthorn species), Prunus serotina (black cherry) |
| Robinia pseudoacacia | Black locust | R species E cultivars |
Catalpa speciosa (Northern catalpa), Gleditsia triacanthos (honeylocust) |
| Ulmus pumila | Siberian elm | R | Dutch-resistant cvs. of Ulmus americana (American elm) |
| VINES AND GROUND COVERS | |||
| Species | Common Name | Status | Alternatives |
| Ampelopsis brevipedunculata | Porcelainberry vine | R | Clematis spp. (clematis) |
| Celastrus orbiculatus | Oriental bittersweet | R | Aristolochia durior (Dutchman's pipe), Celastrus scandens (American bittersweet) |
| Dioscorea batatas | Chinese yam | R | No ornamental alternative; medicinal purposes only |
| Euonymus fortunei | Wintercreeper | E | Asarum spp. (ginger), Helleborus spp. (hellebore) |
| Lonicera japonica | Japanese honeysuckle | R | Clematis spp. (clematis), native Lonicera spp. (native honeysuckles) |
| Polygonum perfoliatum | Mile-a-minute weed | R | ______ |
| Pueraria montana =P. lobata | Kudzu vine | R | ______ |
| Vinca minor | Common periwinkle | E | Asarum spp. (ginger) |
| Vincetoxicum nigrum | Black swallowwort | R | ______ |
| Vincetoxicum rossicum | Swallowwort | R | ______ |
| Wisteria sinensis | Chinese wisteria | W | Wisteria macrostachya (Kentucky wisteria) |
| AQUATICS | |||
| Species | Common Name | Status | Alternatives |
| Alternanthera philoxeroides | Alligator weed | R | ______ |
| Azolla spp. | Water fern | R | Lemna minor (lesser duck weed) |
| Butomus umbellatus | Flowering rush | R | Juncus effusus (common rush), Sagittaria, Schoenoplectus americanus (bulrush) |
| Cabomba caroliniana | Fanwort | R | ______ |
| Eichhornia crassipes | Water hyacinth | R | ______ |
| Egeria densa | Brazilian elodea | R | Elodea canadensis (water weed) |
| Hydrilla verticillata | Hydrilla, water thyme | R | ______ |
| Hydrocharis morsus-ranae | European frog-bit | R | Native Nuphar (yellow pond lily) and Nymphaea (waterlily) |
| Ipomoea aquatica | Water spinach | R | Justicia americana (American water willow) |
| Myriophyllum aquaticum | Parrot feather | R | Elodea canadensis (water weed) |
| Myriophyllum spicatum | Eurasian watermilfoil | R | Elodea canadensis (water weed) |
| Najus minor | Toothed water weed | R | ______ |
| Nasturtium officinale | Watercress | R | ______ |
| Nymphoides peltata | Yellow floatingheart | R | Native Nuphar (yellow pond lily)and Nymphaea (waterlily) |
| Pistia stratiotes | Water lettuce | R | ______ |
| Potamogeton crispus | Curlyleaf pondweed | R | ______ |
| Salvinia minima | Water fern | R | ______ |
| Salvinia molesta | Aquarium water moss | R | ______ |
| Trapa natans | European water chestnut | R | ______ |
Chicago Botanic Garden Conservation Science Department Status:
| R = | Remove as soon as possible, including all cultivars, and/or do not add to collection in future; |
| P = | Phase out (species that pose a lesser invasive risk, form significant structural features in landscape, and will be time-consuming to replace will be phased out over a five- to ten-year period); |
| E = | Evaluate species and cultivars, then remove invasive taxa; |
| W = | Watch list (taxa not posing a serious invasive risk in the Chicago area currently, but may do so in the future). |