Plant Science — Conservation

Invasive Plants in the Chicago Region

Shrubs

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.

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)

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).