USDA Zone 4: Deciduous Shrubs

Azalea, Korean (Rhododendron yedoense var. poukhanense), warmer regions
Azalea, Northern Lights series (Rhododendron 'Pink Lights', White Lights', 'Rosy Lights', 'Orchid Lights', etc.)
Barberry, Japanese (Berberis thunbergii)
Blueberry, highbush (Vaccinium corymbosum)
Buckeye, bottlebrush (Aesculus parviflora)
Buffalo-berry (Shepherdia canadensis)
Chokeberry (Aronia arbutifolia)
Cinquefoil, bush (Potentilla fruticosa)
Cotoneaster, cranberry (Cotoneaster apiculatus)
Cotoneaster, many-flowered (Cotoneaster multiflorus)
Cotoneaster, spreading (Cotoneaster divaricatus)
Corneliancherry dogwood (Cornus mas)
Dogwood, Tatarian (Cornus alba)
Enkianthus, redvein (Enkianthus campanulatus)
Euonymus, winged, also called burning bush (Euonymus alatus)
Filbert, European (Corylus avellana)
Fothergilla, large (Fothergilla major)
Fringetree, white (Chionanthus virginicus)
Honeysuckle, winter (Lonicera fragrantissima)
Hydrangea, panicle (Hydrangea paniculata)
Kerria, Japanese (Kerria japonica), Zone 4b
Lilac (Syringa)
Quince, flowering (Chaenomeles speciosa)
Redosier dogwood, redtwig dogwood (Cornus sericea)
Rhododendron, Korean (Rhododendron mucronulatum)
Rose, redleaf (Rosa glauca or Rosa rubrifolia)
Rose, rugosa (Rosa rugosa)
Serviceberry, downy (Amelanchier arborea)
Serviceberry, Saskatoon (Amelanchier alnifolia)
Silverberry (Elaeagnus commutata)
Smoketree, or smokebush (Cotinus coggygria), in protected areas
Spicebush (Lindera benzoin)
Spirea, Bumald (Spiraea x bumalda)
Spirea, thunberg (Spiraea thunbergii)
Spirea, Vanhoutte (Spiraea x vanhouttei)
St. Johnswort, shrubby (Hypericum prolificum)
Sumac, staghorn (Rhus hirta)
Summersweet clethra, sweet pepperbush (Clethra alnifolia)
Sweet fern (Comptonia peregrina)
Sweetshrub, also Carolina allspice, strawberry shrub, spicebush (Calycanthus floridus)
Tamarisk (Tamarix ramosissima)
Viburnum, American cranberrrybush viburnum (Viburnum trilobum)
Viburnum, arrowwood (Viburnum dentatum)
Viburnum, European cranberrybush (Viburnum opulus)
Willow, dwarf blue-leaf Arctic (Salix purpurea)
Winterberry (Ilex verticillata)