This page provides resources for both the natural areas manager involved in restoration and the gardener looking to avoid the use of potentially invasive ornamental plants.
Native Plant Use in Landscaping (INHS)
University of Illinois Extension
USEPA Illinois Natural Landscaping Resource List
Illinois Best Plants: USDA Plant Hardiness Zones
GLIN: Plants of the Great Lakes Region
Illinois Green Industry Association
Programs Promoting Native Gardening

Cylindrical Blazingstar (Liatris cylindracea) (photo from illinoiswildflowers.info)