trees Invasive Plant Resources


Last Updated March 15, 2006

This section contains Iowa specific information related to invasive plants in forests. Below are lists of problem species, invasive plant monitoring projects, financial assistance programs, state laws, plus links and contacts for more information on invasive plants and organizations within the state. Please let us know if you have suggestions for changes, additions or updates. We need your help to keep this section current and informative. Contact WDNR Forestry (

Return to the Forest Invasive Plants homepage for species factsheets, federal funding sources for management & control, all-states listing of monitoring/mapping projects, research articles & publications, and more.

  1. Current (and Future) Invasive Plants
  2. Invasive Plant Projects (monitoring, mapping, inventories)
  3. Funding and Cost-share Programs for Invasive Plant Control
  4. State Weed Laws & Regulations
  5. Links to State Forestry and Invasive Plant Groups
  6. Contacts

1. Current and Future Invasive Plants

Note: This list is ranked, approximately, from greatest to least threat in Iowa .
[If underlined, click to see factsheet for that species.]

  • Worst Invasives. Species currently causing the greatest problems in Iowa forests.
    • European Buckthorn (Rhamnus cathartica)
    • Garlic mustard (Alliaria petiolata)
    • Asiatic bush honeysuckles (Lonicera spp)
    • Multiflora rose (Rosa multiflora)
    • Reed canary grass (Phalaris arundinacea)
  • Widespread and Localized Invasives. Plants found in forests in much of the state.
    • Japanese knotweed (Polygonum cuspidatum)
    • Japanese barberry (Berberis thunbergii)
    • Siberian elm (Ulmus pumila)
    • Tree-of-heaven (Ailanthus altissima)
    • Burning bush (Euonymus alatus)
    • Dame's rocket (Hesperis matronalis)
    • Black locust (Robinia pseudoacacia)
    • White mulberry (Morus alba)
    • Autumn olive (Elaeagnus umbellata)
    • Glossy buckthorn (Rhamnus frangula)
    • Oriental bittersweet (Celastrus orbiculatus)
    • Norway maple (Acer platanoides)
  • Future Threats. Species that could become serious problems in the future. These plants are invasive in other states with similar climatic and ecological zones.
    • Black swallow-wort (Vincetoxicum nigrum)
    • Japanese hops (Humulus japonicus)

2. Invasive Plant Inventories

Most states have one or more ongoing projects for inventorying, monitoring or mapping invasive plants. These may be state-sponsored or managed by private organizations and groups, and may cover plants statewide or in a specific area. We encourage the sharing of information among these groups to achieve a more complete understanding of invasive plants in each state.

Known projects in Iowa are listed below. Please see also the All-States Invasive Plants Projects & Resources section for a complete list for each state as well as multi-state and nationwide initiatives. We invite additions or corrections to this information – please contact WDNR Forestry (

  • Title: Iowa Woodland Invasive Species Inventory
    • Contact: Jason O'Brien (, NatureMapping Coordinator,
    • Department of Natural Resources Ecology and Management, 339 Science II, Iowa State University, Ames, IA 50011-3221. (515) 294-6440
    • Websites: & NatureMapping
    • Geographic area: Iowa
    • Species tracked: Garlic Mustard, hybrid bush honeysuckle, common buckthorn, and multiflora rose
    • Description: In 2002 and 2003, Iowa State University and the Iowa DNR trained volunteers to survey and map the distribution and abundance of four woodland invasive plants: garlic mustard (Allairia petiolata), exotic bush honeysuckle (Lonicera tatarica and L. maackii), common buckthorn (Rhamnus cathartica), and multiflora rose (Rosa multiflora). Volunteers (primarily landowners) surveyed both private and public woodlands throughout Iowa using a linear transect method, noting presence or absence of the species at regularly-spaced stops along the transect. Data was electronically submitted and stored in a database. Locations are recorded using UTM coordinates (NAD83) and mapped in ArcView 3.2. On the website, maps of Iowa show abundance of the invasives by county. There also are documents explaining the survey protocol, data sheets, species ID and more.

3. Funding and Cost Share Programs for Invasive Plant Control

  • Cost-Share Programs Available for Private Landowners in Iowa .
  • An Iowa DNR Forestry website – – gives thumbnail descriptions of several state-sponsored programs. While not specifically mentioned, managing for invasives is essential for successful projects.
  • Forest Land Enhancement Program (FLEP)
  • FLEP is a federal cost-share program funded through the USDA Forest Service. FLEP funds are administered through the Iowa DNR Bureau of Forestry. All FLEP practices must have a forest stewardship plan written or approved by a District Forester . To review Iowa FLEP Priority Plan click here . For a list of proposed FLEP practices and cost-share rates click here.
  • Conservation Reserve Program (CRP)
  • The Conservation Reserve Program is administered by the Farm Service Agency (FSA) . It cost-shares tree planting on highly erodible land through the general CRP . It also costs shares tree planting on forested riparian buffers and on eligible bottomlands . All CRP programs will pay a landowner an annual rental payment for up to 15 years. For additional and updated information go to
  • Wildlife Habitat Incentive Program (WHIP)
  • The WHIP program is administered through the Natural Resources Conservation Service (NRCS). WHIP provides cost-share reimbursement for wildlife habitat practices. A portion of Iowa 's WHIP allocation will be set aside for woodland wildlife habitat improvement. WHIP will also cost-share on wildlife practices that improve grassland and aquatic habitat. Contact your District Forester , Private Lands Biologist , or District Conservationist for additional information. For additional information click here.
  • Landowner Incentive Program (LIP), Iowa DNR
  • LIP grants provide cost-share of up to 75% to landowners interested in voluntarily enhancing, protecting and restoring habitats in Iowa for threatened and endangered species. DNR staff will visit the landowner’s property and create a Habitat Improvement Plan, including information on at-risk-species on the property as well as habitat recommendations for common species. If approved, landowners will receive cost-share assistance for implementing the changes suggested in the plan. LIP is funded by the U.S. Fish and Wildlife Service and administered by the Iowa DNR.
  • Eligibility : Private landowners. A Forest Stewardship Plan and project plan are required to be eligible for cost-sharing.
  • Contact: Kelly Smith, Iowa LIP Coordinator, (515) 281-6247,
  • Website:
  • Federal LIP information:

4. State Weed Laws

  • The intent of Iowa 's Noxious Weed Law (Chapter 317, Code of Iowa, 1997) is to protect landowners from having their land invaded by weeds growing on adjacent land.  The law gives each county the authority to order the destruction of weeds classified as noxious by the state.  If the owner of the land fails to address the weed problem, the county can assess the owner a fine and control the weeds and charge the landowner for the costs of the control.  Noxious weeds are classed either as primary or secondary, but this status only applies to the Iowa Seed Law.  The Seed Law defines how many weed seeds can be present in certified crop seed.

    Most of the 25 listed weeds are non-forest plants, but several are of concern to forests. Buckthorns -- Common buckthorn (Rhamnus carthartica) and Lance-leaved buckthorn (Rhamnus lanceolata) -- are listed as Primary Noxious Weeds, and Multiflora rose (Rosa multiflora) is listed as a Secondary Noxious Weed.

    Iowa Weed Law:

    The Iowa State University Weed Science program provides a link to Iowa weed laws as well as a listing of noxious weeds with clickable photos and descriptions.

5. Links to State Forestry and Invasive Plant Groups

6. Contacts

  • Iowa District Foresters. Contact information for the 13 state forestry districts.
  • Iowa DNR Customer Phone Center: (515) 281-5918 or see site for specific contact persons.
  • Invasive plants / Forestry
  • John Walkowiak, State Forester DNR Forestry, (515) 242-5966,