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Certified invasive-free landscape products

Certified invasive-free landscape products

Did you know?

Invasive plants and pests can be moved in landscape products like  gravel, fill, mulch and compost.

Unwanted hitchhikers

When landscape products come from infested sites, they can carry:

  • Seeds.
  • Plant fragments capable of reproducing.
  • Invasive jumping worms.
  • Other invasive organisms. 
A woman walks with two children over a small wooden bridge surrounded by heavy vegetation including invasive phragmites.

How does this happen?

  • When invasive or undesirable plants and pests are present where mulch is produced or where gravel and soils are mined, these contaminants can end up in the final product.
  • Improperly treated compost can contain viable seeds and plant fragments from invasive species and other noxious plants.
  • If you’ve ever noticed invasive phragmites or knotweeds emerging after a construction project or seen weeds or garlic mustard along a newly renovated trail, the culprit may be infested landscape products. 

Some problem species

Invasive plants crowd out native and desirable plants, spread aggressively and are difficult and costly to control once established. 
Garlic mustard

Garlic mustard

Tiny seeds from nearby plants easily are transported to new locations in landscape products.
Japanese knotweed

Invasive knotweeds

Plants can reproduce from small fragments of stem or root material. Knotweed rhizomes (underground stems) can infiltrate and damage infrastructure and building foundations.

Phragmites

Invasive phragmites

Phragmites can reproduce from seeds or rhizomes and create tall, dense walls of vegetation.

A shiny reddish-brown jumping worm outstretched on gravel.

Jumping worms

Worms and their cocoons can exist in improperly treated or handled mulch, compost or soil. They consume organic matter and change soil composition.

What can be done?

Michigan is launching a voluntary invasive-free certification program

  • Michigan is joining other states and provinces participating in the North American Invasive Species Management Association’s Weed Free Products program.
  • The Michigan Invasive Species Program is developing a voluntary invasive-free certification program for gravel, fill, mulch and compost.
  • Michigan’s invasive-free certification program, which is planned to launch in 2027, will provide a means for producers to show that their products have been processed, stored and packaged in ways that guard against invasive species spread.
  • Landscapers, contractors, home gardeners and do-it-yourselfers can rest assured that their efforts at property improvement are not undermined by unwanted, hitchhiking invasive species.  
Read more about NAISMA's Weed Free Products Program

Seeking producers of natural landscape products

  • Do you produce gravel, fill, mulch or compost?
  • With certified invasive-free products, you can assure customers that they will not be introducing invasive species with their landscape improvements.
  • If you are interested in contributing to the development of this program or may want to participate, reach out to Vicki Sawicki, DNR Invasive Species Prevention Coordinator, at SawickiV1@Michigan.gov or 231-942-3982.