Legislation: Illinois Exotic Weed Act
Citation and link to full text: Illinois Complete Statutes, Chapter 525 Part 10
Responsible agency and link to landing page: Illinois Department of Natural Resources (IDNR)
Related regulations: N/A
Advisory body and link to landing page: Illinois Invasive Species Council
Key definition(s): Exotic weeds are plants not native to North America which, when planted either spread vegetatively or naturalize and degrade natural communities, reduce the value of fish and wildlife habitat, or threaten an Illinois endangered or threatened species.
Exotic weeds, woody species only (full list in legislation link above):
| Oriental bittersweet Celastrus orbiculatus |
Saw-toothed buckthorn Rhamnus arguta |
| Russian olive Elaeagnus angustifolia |
Common buckthorn Rhamnus cathartica |
| Thorny olive Elaeagnus pungens |
Dahurian buckthorn Rhamnus davurica |
| Autumn olive Elaeagnus umbellata |
Glossy buckthorn Rhamnus frangula syn. Frangula alnus |
| Fragrant bush honeysuckle Lonicera fragrantissima |
Japanese buckthorn Rhamnus japonica |
| Japanese honeysuckle Lonicera japonica |
Chinese buckthorn Rhamnus utilis |
| Amur bush honeysuckle Lonicera maackii |
Multiflora rose Rosa multiflora |
| Morrow’s bush honeysuckle Lonicera morrowii |
Salt cedar Tamarix spp. |
| Tatarian bush honeysuckle Lonicera tatarica |
Prohibited acts:
- Planting or purposeful distribution of seed, live plants, or plant parts for listed species
- Advertising/offering for sale listed species
- Sale of listed species
- Purchase of listed species
Exemptions: IDNR may issue permits to enable plant production for research on listed species control or eradication and for research to demonstrate that a variety or cultivar of a listed species should be exempted by rule. IDNR may also issue permits (to be renewed annually) to manufacturers of value-added products integrating the berries of exotic olives (Elaeagnus umbellata, E. pungens, E. angustifolia). Production of listed species for sale outside of Illinois is broadly exempted.
Cultivar exemptions: IDNR is obligated to initiate exemptions via rule-making if petitioned with evidence that a cultivar or variety of a listed species does not meet the definition of exotic weed (see above). So far, this has not occurred.
Process for species selection/addition: For the 2016 amendment to the Act, species were nominated to the Illinois Invasive Plant Species Council (IIPSC) and approved by vote of the IIPSC Board. The IIPSC consists of a 16-person voting board (8 representatives of the horticultural industry and 8 representatives for natural resources/conservation interests) and a non-voting expert advisory committee. The species nomination form requires the nominator to describe and cite sources relative to the species’ distribution, biology related to its ability to spread, ecological impacts, economic impacts and benefits, and the feasibility of control. The nomination form is populated with qualitative information (i.e. no numeric risk score or rank is given). Decisions to approve or disapprove nominations are made via IIPSC consensus where possible and via majority vote of the Board when consensus is not possible. Approved nominations were conveyed to IDNR and ultimately to the state legislature for inclusion on the Act amendment of 2016. The Act itself is silent on how additional species might be added. Presumably it would require a legislative amendment and a similar nomination and voting process via IIPSC. After a period of inactivity, the IIPSC reformed as the Illinois Invasive Species Council in 2021.
Photo Credit: The sandy dunes and ridges of Illinois Beach State Park give way to black oak forest (Photo: Mike Steele, under Creative Commons license, via Flickr.com)
