We Need Your Voice One Last Time to Support the Six Invasive Species Ban

May 15 is the Last Day to Register to Testify & May 18 for Written Comments on Michigan's Invasive Plant Ban

What We're Asking Is a No-Brainer — Stop the Sales at the Source

The cycle is simple, and so is the fix:

1. Growers and nurseries sell invasive plants to homeowners and landscapers. Plants like Japanese Barberry, Buckthorn, and Callery Pear escape into our parks, forests, and public lands — and they don't stop spreading. 
   
   
2. We spend a lot of time and labor removing these invasives that are sold in our nurseries. Homeowners, city DPW and Parks departments, and the State of Michigan spend millions of dollars every year trying to eradicate the same plants that are still being sold down the street. Michigan has spent over $42 million in state grants since 2014 alone — and that doesn't count what your local tax dollars are paying.
   
   
3. Native alternatives are a win for everyone. This isn't about putting growers out of business. Nurseries just want to sell plants. Native plants are beautiful, increasingly in demand, and far better for Michigan's ecosystem. Transitioning to natives is a win for:
   1. Growers & nurseries — a growing market with real consumer demand for Michigan native plants—
      
      
   2. Cities, homeowners & the State — money spent growing natives instead of removing invasives
      
      
   3. Michigan's ecosystem — healthy forests, clean waterways, fewer ticks, more pollinators

Stop the source. End the cycle. Support the ban.

Why This Matters — The Details

Six invasive species are proposed for regulation:

Prohibit immediately:

• Water Hyacinth
• Water Lettuce

Restrict beginning January 2028:

• Japanese Barberry
• Callery/Bradford Pear
• Common Buckthorn
• Glossy Buckthorn

The cost to Michigan taxpayers is in the millions. Michigan has spent over $42 million in state grants since 2014 — with an estimated $1.5 to $3 million every year devoted to buckthorn, Japanese barberry, and callery pear alone. Oakland Township spends approximately $100,000 annually. Rochester Hills spends approximately $50,000. Multiply that across Michigan's 83 counties and the true cost becomes staggering. As long as these plants remain legal to sell, governments are locked into perpetual management costs — not eradication, just keeping up.

The ecological harm is real. Japanese Barberry is a tick magnet — its dense, humid thickets create ideal conditions for black-legged ticks that carry Lyme disease. Where barberry is controlled, tick populations and infection rates drop. Water hyacinth and water lettuce clog waterways, kill fish, and require expensive removal — yet both are still legally sold in Michigan today.

Other states have already acted — Michigan is behind.

• Callery Pear — banned in Ohio and Pennsylvania
• Japanese Barberry — banned in Massachusetts, Maine and Minnesota
• Common & Glossy Buckthorn — banned in Illinois, Minnesota, Wisconsin, New York and Massachusetts
• Water Hyacinth & Water Lettuce — banned in Florida, Louisiana, Texas, California, Alabama and Mississippi

"Sterile" cultivars are not a reliable safeguard. Plants marketed as sterile — including Callery pear and purple loosestrife — have repeatedly proven otherwise through cross-pollination and genetic reversion. Sterility cannot be reliably guaranteed outside controlled research settings.

The full Michigan Commission of Agriculture and Rural Development will vote on this proposal — not MDARD Director Dr. Tim Boring alone. Please contact the Commission directly.

HOW YOU CAN HELP:

Email all three Commission members today:

• Dr. Felicia Wu, Commission Chair — WuF@michigan.gov
• Andy Chae — chaea@michigan.gov
• Monica Wyant — WyantM1@michigan.gov
• Full Commission — MDA-Ag-Commission@michigan.gov

Three ways to act:

1. Register to testify — email today, Friday May 15 (last day)
2. Submit a written comment — email by Monday May 18 at 11:59 PM
3. Attend the meeting — Wednesday, May 20, 9 AM in Lansing or via Teams: dial 1-248-509-0316, Conf. ID: 174 280 339#

Every public comment becomes part of the official record. Your voice matters — and right now, it matters more than ever.

Michigan is one vote away from restricting the sale of six invasive plant species that are costing taxpayers millions of dollars and causing irreversible harm to our forests, waterways, and public health.

The Michigan Commission of Agriculture and Rural Development meets Tuesday, May 20 — and what happens in that room will determine whether Michigan continues paying to clean up plants that are still being legally sold down the street.

To join the meeting via Microsoft Teams: by telephone dial: 1-248-509-0316 and enter the Conference ID 174 280 339# or by video conference visit www.michigan.gov/mdard/about/boards/agcommission to join the day of the meeting.

The Meeting Agenda is at the end of the blog post.

Here's why this matters — and why Michigan can't afford to wait any longer.

Restrict:

• Japanese barberry (Berberis thunbergii) 
• callery pear (Pyrus calleryana)
• common buckthorn (Rhamnus cathartica) 
• glossy buckthorn (Frangula alnus)

Details: Begins January 2028. Sale and cultivation allowed in 2026-2027.

Prohibit:

• water hyacinth (Eichhornia crassipes) 
• water lettuce (Pistia stratiotes) 

Details: Begins 30 days after signing the order.
Rationale: These species are not horticulturally produced in high numbers in Michigan; they are not yet widespread in Michigan; and immediate action will better protect Michigan’s aquatic ecosystems. Compliance can be achieved through order management

Rationale: These species are currently widespread in the landscape and may be horticulturally produced in Michigan. Restriction is key to limiting harm to terrestrial ecosystems while reducing impact to industry. Compliance can be achieved through selling existing stock during the phase-out period.

Basis for Action:
These species are widely established across Michigan and are currently present in horticultural production and trade. A restriction, rather than an immediate prohibition, provides a measured approach that limits further spread while allowing time for industry adjustment and depletion of existing inventory. This approach is consistent with invasive species management practices that balance ecological risk reduction with economic considerations.

Other States Have Banned Them because of the Harm that They Do—Michigan Has Them on Thier Invasive Species List
    •    Callery Pear banned in Ohio and Pennsylvania 
Callery pear forms dense thickets that crowd out native trees and wildflowers, leaving little to no habitat for birds or pollinators. Callery pear supports almost no native insects or wildlife, while native flowering trees like Serviceberry, which supports over 120 species of caterpillars, Black Cherry, which supports over 450, and the mighty Oak Tree, supporting over 564 species!
    •    Japanese Barberry Banned in Massachusetts, Maine and Minnesota
Japanese barberry creates humid thickets ideal for ticks that carry Lyme disease, alters soil chemistry, and displaces native shrubs. Its seeds are dispersed by birds and wildlife. Plants are not browsed by livestock or wildlife due to thorns, giving it a competitive advantage over native plants. 
    •    Common and Glossy Buckthorn Banned in Illinois, Minnesota, Wisconsin, New York and Massachusetts
dominate woodlands, trail edges, and wetlands, displacing the native plants that pollinators and wildlife depend on.
    •    Water Hyacinth and Water Lettuce Banned in Florida, Louisiana, Texas, California, Alabama and Mississippi They clog waterways, kill fish by reducing oxygen, and require expensive removal — yet both are still legally sold in Michigan nurseries today.

Because many other states have already taken similar action to restrict or ban these species because of their proven ecological and economic harm, it should not be difficult for Michigan to follow suit. Michigan should not have to keep paying the price for plants that other states have already recognized as destructive.

“Sterile” Cultivars Are Not a Reliable Safeguard (Evidence-Based)

Claims that invasive plants can be made safe through “sterile” cultivars are not supported by long-term scientific evidence. Numerous plants marketed as sterile or self-sterile have later been shown to regain fertility through cross-pollination, genetic instability, or reversion, contributing to widespread invasion. Well-documented failures include Callery pear, purple loosestrife, butterfly bush, rose-of-Sharon, and privet. Research also shows that even large reductions in seed production do not necessarily prevent the spread of populations in long-lived invasive plants. Because sterility cannot be reliably guaranteed outside controlled research settings—and because sterile non-native plants are not ecological equivalents of native species—many states have adopted a precautionary, prevention-based regulatory approach.

Sources:

• Gould, L.L. (2023). “Chlorofiends! What’s Up With ‘Sterile Cultivars’?” Native Plant News, North Carolina Native Plant Society.

• Nature’s Best Hope — Doug Tallamy documents the limited ecological value of non-native ornamental plants, including sterile cultivars.

• Simberloff, D. et al. (2011). “Impacts of biological invasions.” BioScience — shows that reduced fecundity alone often fails to prevent invasive spread.

• US Forest Service & university extension research documenting cross-pollination and fertility restoration in Pyrus calleryana and Lythrum salicaria.

Every public comment becomes part of the official record and helps demonstrate broad public support for preventative action.

Bottom Line for Commissioners:

Approving this regulation:
    •    Protects taxpayer investment
    •    Reduces future fiscal liabilities
    •    Aligns Michigan with best practices in invasive species management
    •    Advances MDARD’s core mission responsibly and proportionately

This action is necessary, fiscally sound, and overdue.

We urge YOU to share your thoughts about this proposal to the email above! If you have questions or comments you want to share with us, please email: