When I last wrote to you, my garden seemed dead. A few Hepatica acutiloba (sharp-lobed hepatica) flowers were coming up, but little else was happening. I had hoped the cold, snowy winter—like the ones I remember from my youth, before the climate seemed to go haywire—would have been good for the garden, but the herds of deer that roam our town were ravenous and devoured my Rhododendron maximum (rosebay rhododendron) and Kalmia latifolia (mountain laurel), plants that are toxic to them. The nets I hurriedly threw over the plants didn’t help once the snow weighed them down and the deer could reach the leaves again.
Today, the shrubs still look butchered, and some are bound to die, but at ground level, the garden is in full bloom. Thousands of spring ephemerals and ferns are reminding me that life comes back, so long as it is tended and protected. Mertensia virginica (Virginia bluebells) are spreading into blue drifts across my forest floor alongside Podophyllum peltatum (mayapple). Trillium spp. (trilliums) are blooming everywhere, while Sanguinaria canadensis (bloodroot) and Jeffersonia diphylla (twinleaf) have already had their brief blooms. Matteuccia struthiopteris (ostrich fern) is nearly full size, while Polystichum acrostichoides (Christmas fern) and Osmundastrum cinnamomeum (cinnamon fern) are beginning to unfurl. This is the narrow window before the trees leaf out, when sunlight still reaches the ground, and the forest floor can flower—one of the most beautiful times in the native plant year.
The tragedy is that it would be hard to find anything like this in most forests and parks in our state. In too many places, the spring flora has been browsed down by deer and eradicated. Deer browse is a huge problem for native plants in our state, more immediately destructive to the forest understory than climate change. Climate change alters the conditions under which forests grow, but deer can turn the next forest into a veritable biodiversity desert, browsing down native plants while leaving invasive species behind. Due to the topography of my yard, I can’t build a deer-exclusion fence, but a maze of Orbit Garden Enforcer motion-activated sprinklers protects most of my plants during the growing season, allowing my garden to function as a small refugium in a state that now has more deer than at any time before European colonization. Without that protection, much of what is flowering here would simply be gone.
Sadly, the problem isn’t limited to New Jersey. On a recent trip to Japan, I saw how sika deer—native there, just as white-tailed deer are native here—have damaged forests and wetlands when their numbers rise beyond what the land can bear. In parts of Nikkō, deer browse has helped turn the understory over to Sasa nipponica (dwarf bamboo), a native plant that can form dense, persistent carpets and suppress much of the rest of the forest flora. The lesson is not simply that deer are a problem. It is that a species does not have to be non-native to become ecologically overwhelming. We have smaller warnings here—Dennstaedtia punctilobula (hay-scented fern), for example, can expand after heavy deer browse and disturbance—but Japan shows how severe native super-abundance can become when the checks on abundance disappear. I won’t usually promote my own website in these letters, but if you are interested in this topic, I wrote about it in greater depth on my blog.
Humans are part of this story, too. We are not outside nature looking in; we are a native species almost everywhere we live, and the most super-abundant native species of all. Super-abundance of deer is a crisis we created by exterminating predators and then avoiding difficult management questions for decades. If we care about spring ephemerals, birds, forests, and the future of native plants, we have to talk honestly about native super-abundance—and our role in creating it. Until then, all we can do is build refugia.
I also want to offer an apology about this year’s Native Plant Month BioBlitz. I had not realized that the project was set to exclude non-native and cultivated species. That was my mistake. Native-only data is valuable, but so is the broader record of what is actually growing in New Jersey—native, introduced, invasive, and cultivated. Next year, we will plan for two concurrent BioBlitzes: one focused on native species, and one open to all plant observations. Both kinds of data matter.
Thank you to everyone who observed, planted, taught, volunteered, and paid attention during this National Native Plant Month.
Happy gardening,
Kazys Varnelis, Ph.D.
President, the Native Plant Society of New Jersey
It’s still March for a few hours, so it’s time for my much belated President’s Letter. I had hoped to write to you after the Annual Meeting, but as those of you who watched may recall, I caught the flu and that knocked me out for a while. This was a meeting and conference I worked hard on and was proud of, so it was a real disappointment, but such things happen. I am so grateful to everyone who volunteered to help and to our speakers, who were just fabulous. Thank you to everyone who participated and everyone who attended.
James and Kathy’s talk will be on YouTube by the end of April. For now, you can see them (together with Larry’s talk which is only up for ticket purchasers and only for 3 more weeks) on the meeting portal if you bought tickets (if there is demand for folks to see Larry’s talk or you really want to see the other two, drop me a line and we can create a ticket for you).
After we recovered, we embarked on a long trip to Japan to visit our kid, who is studying at college in Tokyo. It’s my fourth trip to Japan, and my wife Jennifer and I visited gardens in Tokyo, Kyoto, and Nikko. It was a fabulous trip, though also mixed with some concerns that the problems we have with biodiversity loss are common there, too. More on that next month.
But I’m back in New Jersey now, and in these last hours of March, when my Virginia Bluebells (Mertensia virginica) and Toadshade Trillium (Trillium sessile) are coming up in my garden, and my Sharped-lobed Hepatica (Hepatica acutiloba) are blooming, I am looking forward to April, which is once again Native Plant Month in the United States.
So, I have two announcements.
First, our third annual BioBlitz is underway. Throughout April, we’re asking you to photograph plants across New Jersey—in parks, backyards, roadsides, anywhere—and upload your observations to iNaturalist, a fantastic citizen science program. Search for “Native Plant Month – April 2026 – NJ” on iNaturalist or go directly to https://www.inaturalist.org/projects/native-plant-month-april-2026-nj.
Last year, 32 observers recorded 2,041 observations of 401 native species. Let’s beat that. Every observation contributes to our understanding of plant distribution and biodiversity in the state. iNaturalist runs on both iOS and Android. Don’t worry if you can’t identify a plant! iNaturalist has the best machine learning around, and you can use it to identify plants (a tip: I prefer the interface on iNaturalist Classic on iOS to the new one). If you’re documenting endangered species or private locations, use iNaturalist’s “obscure” feature to protect their exact locations, and mark if it’s captive or cultivated. If you’re new to iNaturalist, these two short Youtube videos will get you started: How to Make an Observation on iNaturalist using our Mobile App and How to prepare for a bioblitz: iNaturalist tutorial.
Second, I wanted to remind you that grant applications are due by 11:59 PM on April 15. We’re offering mini-grants of $500 or $750 for native plant gardens, conservation, and education projects, as well as two conservation/science grants of $2,000 each for large-scale projects led by scientists.
The Native Plant Society of New Jersey is accepting applications for two grant programs for 2026.
Mini-Grants
NPSNJ is offering mini-grants of $500 or $750 to local volunteer organizations, schools, individuals, and groups working to:
Create native plant gardens and wildlife habitat in community gardens and public green spaces
Engage in conservation or restoration
Engage in education and outreach about the native plants of New Jersey
Conservation/Science Grants
NPSNJ’s 2026 grant cycle will also fund two conservation/science grants of $2,000 each. These grants are intended to support large-scale projects headed or advised by a scientist—for example, a PhD in ecology, entomology, or a related science; a Rutgers Agriculture and Natural Resources Agent; or a certified arborist. The grant will most likely fund a part of an ongoing project.
Eligibility
For both grant programs, applicants (or their non-profit organizations) must reside or be based in New Jersey, must be current members of NPSNJ, and the project must be based in New Jersey. Non-profit organizations may join as non-profit members or apply through a member sponsor.
How to Apply
The application deadline for both programs is 11:59 PM on April 15, 2026. Grants will be awarded during the summer of 2026.
Happy Groundhog Day! I have two bits of good news for you. First, tickets for our Annual Meeting go on sale this Friday, February 6, at 10 am. The meeting is Saturday, March 7, at Ocean County College in Toms River, sponsored by Ocean County College, Jersey Friendly Yards, and Barnegat Bay Partnership, or online via Zoom.
This year’s theme is resilience—how we adapt to environmental uncertainty. Three speakers bring complementary perspectives from design, ecology, and hands-on horticulture: renowned landscape designer Larry Weaner, FAPLD, on ecological landscape design; Dr. James Shepherd of Yale on how biodiversity loss affects human health; and former NPSNJ president Kathleen Salisbury on the Ambler Arboretum’s recovery from a catastrophic 2021 tornado.
Whether you’re new to the movement, a seasoned practitioner, or a landscape professional, there will be something for you here: why ticks and Lyme disease are spreading (and why we need to plant more native plants), what catastrophic storms do to landscapes, and how to design native plant landscapes, big or small, for change rather than against it. In-person attendees will find informative tabling, the Nature of Reading Bookstore (including book signings with Larry Weaner and Wildstory co-host Ann Wallace), and time at lunch to meet others in the Society. We are trying a new caterer this year, so we hope the lunch options will be better.
Full details and tickets on our website.
In-person tickets are $60 (members only); Zoom tickets are $30 for non-members, $20 for members. Membership is only $25, so be sure to sign up today.
We will have a large number of Continuing Education Units available for those who need them: Details and tickets at npsnj.org/event/2026-annual-meeting. In-person tickets are $60 (members only); Zoom tickets are $30 for non-members, $20 for members. Membership is $25. CEUs available for those who need them: 3 NJLTE/LTCO, 3 ISA, 3 NOFA OLC, 3 SER CERP, 2 Urban Forestry
Second, Governor Phil Murphy signed the Invasive Species Management Act on his final day in office, giving New Jersey its first law regulating invasive plants. I want to thank everyone who called or wrote—our continued pressure was essential.We were one of the only states without a list of prohibited species. Now we have one: 31 invasive plants to start, including familiar villains like Callery pear, Norway maple, Japanese barberry, winged euonymus, tree-of-heaven, and autumn olive. Pinelands Nursery made this excellent visual guide to the now-prohibited plants.
Critically, the New Jersey Invasive Species Council, originally created under Governor McGreevey in 2004, will also be reestablished. That Council produced a 220-page Strategic Management Plan, which documented a $290 million annual economic impact on agriculture and found that 30% of the state’s flora were nonnative. Governor Christie disbanded it in 2010, supposedly because of the financial crisis. The council will now have the authority to review the species list every three years and add emergent threats before they become the next barberry. Under the law, Acting Commissioner Ed Potosnak must convene the Invasive Species Council within 60 days, and the DEP must adopt implementing regulations within 12 months. He’s the former executive director of the NJ League of Conservation Voters and widely respected—so we have high hopes he will continue to advocate for the environment in his new role.
This victory was years in the making. In 2022, when Laura Bush and I were co-chairs of Advocacy, we worked with partners including John Landau of Foote’s Pond Wood, Mike Van Clef (Program Director of the Friends of Hopewell Valley Open Space Invasive Species Strike Team), and the New Jersey Nursery & Landscape Association—whose president, Tom Knezick of Pinelands Nursery, helped bridge conservation and industry interests. The bill won bipartisan support, only to be vetoed by Governor Murphy. It again passed with bipartisan support, but Murphy only signed it on his last day in office, and the announcement came only after Governor Mikie Sherrill—a supporter of native plants during her time in Congress—was inaugurated.
Special thanks to our Advocacy Committee, former co-chair Laura Bush and current co-chair Russ Furnari, who represented NPSNJ throughout the legislative process and provided testimony in Trenton, and, once again, to all of you who reached out.
One last thing. Larry Weaner will be speaking on the next episode of the Wildstory podcast. And if you haven’t taken the Rutgers Environmental Stewards Survey, please do. The team will be very grateful for more responses.
Join us Saturday, March 7, at Ocean County College (or online via Zoom) for our annual symposium exploring restoration, resilience, and disease in a changing landscape.
This year’s speakers bring perspectives from ecological design, infectious disease ecology, and arboretum management: Larry Weaner, FAPLD, on integrating ecological restoration with landscape design; Dr. James Shepherd of Yale on biodiversity loss and tick-borne disease; and Kathleen Salisbury on the Ambler Arboretum’s recovery from an EF2 tornado. Go to the 2026 annual meeting page for more.
Tickets go on sale soon. In-person tickets include lunch, a Zoom link, and early access to conference videos. Zoom tickets will also include early access to conference videos. In-person tickets are for members only.
Participants (in person or online) who need Continuing Education credits can earn 3 NOFA OLC CEUs, 3 ISA Credits, 3 JLTE/LTCO CEUs, and 2 Urban Forestry CEUs by attending.
On his final day in office, Governor Phil Murphy signed the Invasive Species Management Act into law. After years of advocacy—and a frustrating veto just two years ago—New Jersey finally has legislation to address the invasive plants degrading our native ecosystems.
This bill passed both houses of the Legislature without a single opposing vote, with bipartisan support of 39-0 in the Senate and unanimous approval in the Assembly. The same thing happened in 2024, when an earlier version passed unanimously before Murphy vetoed it, citing concerns about DEP’s existing authority.
The law prohibits the sale, distribution, import, export, and propagation of certain invasive plant species without a permit from the Department of Agriculture. It also reestablishes a permanent New Jersey Invasive Species Council in statutory law. The Council was originally created by Governor Corzine in 2004 but disbanded under Governor Christie in 2010. With 19 members representing state agencies, environmental organizations, agriculture, the nursery industry, and academia, the Council will advise the state on invasive species identification and management.
The DEP will create an online clearinghouse with information on identifying invasive species, management best practices, and lists of native alternatives. Violations carry penalties up to $5,000 for repeat offenses.
This is long overdue. New Jersey was one of only five states without an invasive species law, even as our neighbors—New York, Pennsylvania, and Delaware—had already taken action. Species like Japanese barberry, burning bush, and Callery pear have been freely sold for years while spreading throughout our forests and outcompeting native plants.
It took until the governor’s last hours in office, but New Jersey finally has a law to fight back against invasive species.
List of banned species
Norway maple (Acer platanoides)
Tree of heaven (Ailanthus altissima)
Mimosa or silk tree (Albizia julibrissin)
Porcelain berry (Ampelopsis glandulosa var. brevipedunculata)
The critically imperiled Hammond’s Spring Beauty (Claytonia virginica var. hammondiae), which only grows in a couple of areas in the state
Did you know that New Jersey has 862 rare plants the DEP is tracking? Of those, 355 are threatened to go extinct. For about 35 years, NJ has been tracking them with the Endangered Plant Species List. This important list helps protect these species from going extinct.
The good news is that after more than 10 years, the DEP has updated the Endangered Plant Species List. However, the Governor needs to sign off on the list. Until he signs off, it cannot proceed to public comment and final adoption.
Please call Governor Murphy today to SIGN OFF on the new list so it can proceed onto Public Comment and Adoption. Thank you for all you do for New Jersey’s biodiversity.
Our Weird NJ Plants conference was another success, with hundreds of members attending. If you missed it, view the whole thing at https://npsnj.org/event/fall-conference-2025/ or directly on our Youtube channel. I made a flub in my introduction to Kate’s talk. I said day lilies (Hemerocallis) are native and aquatic. They are neither. I meant American white water lillies (Nymphaea odorata), which are very lovely in my tiny forest pond. American white water lily (Nymphaea odorata) in my forest pond.
American white water lily (Nymphaea odorata) in my forest pond.
You may have noticed we have a governor-elect now. As a 501(c)(3), NPSNJ doesn’t endorse candidates, but we can advocate for native plant policies regardless of party affiliation. Mikie Sherrill promoted native plants in legislation as a congressional representative so we have high hopes for an improved situation in Trenton. If native plant advocacy matters to you, consider reaching out to her transition team here to encourage her to continue this work as governor.
We also have a great new benefit! Members will get a 10% discount on regional events in the Mid-Atlantic with New Directions in the American Landscape, starting with their 37th Annual Symposium at Kean University in Union, NJ (January 15-16 with virtual options available). The discount code will be in the member portal once you log into the website. Please do not share it! Larry Weaner, NDAL’s founder, will be speaking at NPSNJ’s 2026 Annual Meeting on March 7.
A new round of classes for members is starting up. All classes are on Zoom and are $160 with a max of 30 people so the students can engage more closely with the instructors. Everything but $10 goes to pay the instructors so you can get top quality classes.
March: Dr. Drew Lanhem in March teaching Cultural Ornithology and Conservation. Registration opens Dec. 15.
If you’re a PK-12 teacher or know one, Wild Seed Project is offering free native seed packets to public school educators through their Seeds for Teachers program. Each classroom receives bulk seeds for four easy-to-sow, pollinator-friendly species, perfect for hands-on environmental projects. The deadline to request seeds is very soon November 14th. Click here
Each of these letters has a theme and, in this letter, I want to address a question I hear often: What can I do to help the Society?You’re probably already helping more than you realize. Every time you choose native plants for your garden, share knowledge with a neighbor, or attend one of our programs, you’re advancing our mission. But for those looking to do more, let me share some concrete ways you can support NPSNJ’s work.
Volunteer Opportunities
We have openings for people who want to shape NPSNJ’s future. Our Corresponding Secretary position is perfect for someone interested in strategic communications—you’d help build partnerships with organizations like other native plant and conservation societies both in New Jersey and beyond, coordinate speaker invitations, draft press releases, and maintain media relationships. You’d be at the heart of how we connect with the broader native plant community. Plus, it is an executive committee position, and that is the heart of our state effort. It is a bit of work, but it’s a lot of fun, with a great team.
We’re also looking for a leader for our Highland Park Chapter in Middlesex County, and our Delaware Bayshore Chapter is seeking people to join their steering committee.
Financial Support
With Giving Tuesday on December 2nd, this is an ideal time to consider supporting our mission. As an all-volunteer organization, there are no staff salaries or administrative overhead. Unlike some organizations, we don’t send out junk mail asking folks to join. Our membership system is now electronic and free of paper for everyone except those who expressly opt out. If you need to renew your membership, now is the perfect time. We keep our membership fees lower than almost anybody else out there, but if you can afford to upgrade your membership, we would greatly appreciate it and it will go to good causes. And yes, your membership is fully tax deductible. Many employers will match your contribution (we are on Benevity if your workplace uses that).
Your contributions fund speaker honoraria for our Wednesday webinars, support our fall conference and spring meeting, support chapters, keep the web site running, help us with the grants we give out, enable us to print our publications, and help us keep most programming free.
Consider these two options:
Our Annual Fund supports core NPSNJ operations throughout the year.
Our Mini Grants and Conservation Science Fund provides crucial funding for local projects—school gardens, community plantings, and initiatives that often seed larger efforts benefiting entire communities.
You can donate to NPSNJ at our donations page and direct your funds either way, based on your preference.
Estate planning through bequests of any size helps secure our educational mission for future generations. A generous bequest from Bruce Wands funded our mini grant program this year.
Perhaps you’re not in a position to give financially right now—that’s completely understood. Help comes in many other forms. Share our Wednesday webinar announcements with friends who might be interested. Volunteer with your local chapter. Offer to help with simple tasks. Post about what we do on social media.
Most importantly, keep learning and sharing what you know. Native plant advocacy happens one conversation at a time, one garden at a time, one neighbor at a time.As we head into the Thanksgiving season, I’m grateful for this community of over 1,600 members who understand that protecting New Jersey’s native flora requires both individual action and collective effort. Whether you volunteer, contribute financially, or simply share what you’re learning with your neighbors—your participation matters. That’s how movements grow. Kazys Varnelis, Ph.D.President, NPSNJ
These days, it seems that when people make mistakes they just double down. Whatever your political position, I think we can all agree our government is full of politicians doing that. But in striving to make the native plant world a better community, we should do the opposite. Mistakes are something we can learn from.
In my last e-mail to you, I made a couple of gaffes and a few of you pointed them out, but rather than merely adding an errata section to this letter, I thought it would be interesting to spend a little time thinking about mistakes in the native plant world.
But, first, a reminder that we have our Weird NJ Plants conference at 8:50 in the morning of November 1, the day after Halloween—free to everyone via Zoom. The speakers and I created a slideshow full of creepy images, and our webmaster Marissa Bauman made a spooky logo.
Dead Man’s Fingers (Xylaria polymorpha), is a fungus that feeds on decaying hardwood stumps and roots, forming clusters of erect, black, finger-like fruiting bodies up to 8 cm tall, often emerging in temperate woodlands during spring and autumn. Photo courtesy, Jason Hafstad on iNaturalist.
Dead Man’s Fingers (Xylaria polymorpha), is a fungus that feeds on decaying hardwood stumps and roots, forming clusters of erect, black, finger-like fruiting bodies up to 8 cm tall, often emerging in temperate woodlands during spring and autumn. Photo courtesy, Jason Hafstad on iNaturalist.
Go take a look at the site and please share it with at least one other person, especially young folks like college and high school kids as well as people who have never thought about native plants. Let’s get them into a lifetime of fascination with the botanical world. If you have shared it with every last person you know in New Jersey, great, but we are delighted to have people from outside the state attend. Most of these plants live throughout the Northeast and Mid-Atlantic so let them know too.
Two more quick announcements: our Fall Newsletter came out last week and it focused on Weird NJ Plants. I also discussed the fall conference in the 25th episode of the Wildstory podcast, which features poet Holli Carrell, naturalist Mary Ann Borge, and another episode of Ask Randi.
Now for the last letter. I started with a typo: Trillium erectum not Trillium erechtum for the red trillium (or wake robin, purple trillium, or stinking Benjamin). Ouch. But that’s nowhere near as egregious as the caption in which I stated that American pokeweed (Phytolacca americana) is an annual. Of course it’s not! Pokeweed is a robust perennial with a large taproot. I knew this, but somehow the wrong neuron misfired when I wrote the caption, just like in my talk for NPSNJ last year when—inexplicably—I kept saying Cardinal flower (Lobelia cardinalis) when I meant Scarlet Beebalm (Monarda didyma). I know these things well!
But here’s the thing about mistakes: we’re all going to make them. What follows is my longest letter to date. Feel free to skip it, but I found this deep dive into native plant mistakes fascinating and I hope you do too.
Looking back at my own relationship with the land, I realize I’ve made mistakes. The worst was back in the early 1980s when my father and I decided to turn a meadow on our property in the Berkshires into a lawn. It was full of goldenrod (Solidago spp.) and sensitive fern (Onoclea sensibilis), but also invasives like Queen Anne’s lace (Daucus carota… and yes, it’s the wild version of the root vegetable) and mugwort (Artemisia vulgaris). Still, it was a lovely place, full of buzzing insects. We had no idea what we were doing. What were we thinking, destroying a thriving community?
At least my father and I had better sense another time. Foresters came by our house to explain that we could make money by having them log the wooded hill behind our house. We weren’t wealthy and more money was an appealing idea, so we visited one of their “managed” forests. They talked about the benefits of young forests for wildlife, but we both agreed it looked like hell. We ran. We never allowed foresters on our land and a good thing, too. At least part of that property contains old growth forest, something nobody knew until decades later. It’s still there, although it has been seriously hurt in recent years, not by logging but by Emerald Ash Borer and Hemlock Woolly Adelgid—themselves the product of serious mistakes in global trade. The borer arrived in wooden crates and pallets while the adelgid came through ornamental hemlock trees from Japan.
Unfortunately, I think a lot of us have stories like that. Well, we can’t change the past, but what we do now matters. Moreover, the history of botany and horticulture is full of mistakes, big and small. Common names for plants are full of them. Early colonists made countless naming errors because they tried to fit unfamiliar American plants into familiar European categories. They called our native juniper, Juniperus virginiana, “red cedar” even though it’s not a true cedar at all. Carl Linnaeus, the father of botanical taxonomy, made plenty of mistakes too. For one, he originally classified Twinleaf, now Jeffersonia diphylla, in the genus Podophyllum thinking it was a kind of Mayapple. It was only decades later that it would be understood as a distinct genus, although in fairness both are in the family Berberidaceae (as is the very different Japanese barberry, poster child of invasive ornamentals Berberis thunbergii).
Those are small mistakes, but there were plenty of big ones, sadly. In the 1930s and 1940s, the U.S. Soil Conservation Service actively promoted multiflora rose (Rosa multiflora) as a “living fence” for livestock and a solution for erosion control. State highway departments put it in medians as crash barriers. It seemed like the perfect plant—wildlife could eat its rose hips, thorny thickets would confine cattle, and it would stabilize streambanks. By the 1960s, alarm bells were ringing. Multiflora rose had escaped those farm hedges and was forming impenetrable thickets in pastures and woodlands, crowding out native plants. The same USDA that once promoted multiflora rose was now warning farmers to root it out. Decades of expensive eradication efforts followed—all because of a well-intentioned misjudgment.
The pattern repeated with autumn olive (Elaeagnus umbellata), Norway maple (Acer platanoides), and Bradford pear (Pyrus calleryana). Each time, experts thought they had the perfect solution: a hardy plant for reclamation, a replacement for elms lost to Dutch elm disease, a sterile ornamental that wouldn’t spread. Each time, they were wrong. These mistakes now cost us millions of dollars annually in invasive plant control.
A monoculture stand of Phragmitis australis in Cape May that has outcompeted any other flora.
But other mistakes get more complicated. Take the common reed (Phragmites australis), which now frequently chokes our wetlands. Until recently, I had thought that Phragmites was merely another invasive species. Well, that’s another mistake. Phragmites has been in North America for tens of thousands of years and Native Americans historically used it for arrows, mats, and ceremonial objects. Nonetheless, it was a relatively minor component of marshes, not the dense monoculture we commonly encounter today.
Researchers puzzled over how this native plant could suddenly become so aggressive. Perhaps it was responding to altered conditions in the landscape. In 2002, molecular ecologist Kristin Saltonstall compared DNA from century-old herbarium specimens with modern reeds and discovered a surprising explanation (you can read her paper here). The invasive Phragmites overwhelming the Northeast today is genetically distinct—a Eurasian strain introduced to North America in the late 18th or early 19th century. Genetic evidence clearly shows that this Eurasian strain (known as haplotype M) displaced native North American strains along the Atlantic coast and spread rapidly throughout the continent, facilitated by human activities such as transport and marsh disturbances.
Simultaneously, entomologist Lisa Tewksbury, et al. found that while over 170 herbivore species feed on Phragmites in its native European range, only five native North American herbivores attack it here (unfortunately, that paper is gated, but you can read a detailed guide she wrote over at NOAA). Botanists had long mistaken the invasive Eurasian strain for the native one, a phenomenon Saltonstall labeled a “cryptic invasion,” hidden by mistaken identity. Saltonstall discovered that native Phragmites have been almost completely displaced by the invaders, and remnant populations only exist in isolated pockets (in 2007, there were a few left on the Cohansey River in Cumberland County).
Another example is the hart’s-tongue fern, Asplenium scolopendrium, a fern common in Europe but rare in North America. Our native variety, A. scolopendrium var. americanum, survives mainly in New York, Michigan, and Ontario, with small, isolated colonies in places as unexpected as limestone caves in Alabama and Tennessee and even in a lava-tube cave in New Mexico. NatureServe Explorer notes an introduced population in New Jersey, the result of ex-situ conservation plantings begun in the 1930s, and I was thrilled when, a while back, I found some at a local garden center. Unfortunately, genetic studies show that plantings such as those in New Jersey—and any plants offered for sale—derive from European stock, genetically distinct from the American lineage. In some of New York’s native populations, European DNA appears along the margins of some sites, the result of well-intentioned restoration efforts that inadvertently blurred the line between native and introduced forms (See Heo, 2022 or this excellent podcast episode of the Field Guides with hart’s tongue fern expert, NYS conservation biologist Michael Serviss).
A few years back, when I still bought cultivars, I fell victim to this confusion. I purchased a pretty plant labeled “Lance Corporal” Virginia Jumpseed (supposedly Persicaria virginiana) from a garden center. It said native, so of course it was native—right? Plus, it had such pretty red flowers, unlike the more common one with its white flowers. Well, this plant spread all over my yard and acted wildly aggressive, nothing like the well-behaved native. It turns out that whoever labeled that plant should have labeled it Persicaria virginiana var. filiformis, to indicate this was an Asian variety (these days it seems to be considered not just a variety, but its own species, Persicaria filiformis … read more at the Maryland Invasive Species Council). There is absolutely no evidence that this cultivar, apparently developed from a chance seedling at Rowden Gardens, an exotic plant nursery in Devon, England, is native to the US. But it was good marketing, right? I’m still pulling up this plant years later.
As I ponder these examples: native plants mistaken for invasives, invasive strains mistaken for natives, European genetics contaminating American populations—I find myself questioning the use of cultivars altogether. These have been the subject of much debate lately, and we are assured that some cultivars are harmless, that they won’t spread or hybridize with native populations. But do we really know this? How long will they remain harmless? Haven’t we heard such assurances before? The history of botany is littered with confident predictions that proved disastrously wrong. Each time, we’re told this is different, that we understand the risks now. Each time, it turns out we don’t. Perhaps the only honest answer is that we’re running yet another uncontrolled experiment—this time in our own gardens. I’ve decided to tread carefully with cultivars and avoid them when I can. There’s always a better straight-species native around if I hunt a little.
Mistakes are how we learn, but only if we’re willing to admit we made them. My pokeweed error was embarrassing but harmless. Introducing multiflora rose, misidentifying an invasive reed as native for a century, contaminating native hart’s-tongue populations with European genetics in the name of conservation—these mistakes have consequences that can’t be undone. Yet at each step, someone was confident they knew what they were doing. The pattern repeats: we intervene, we assure ourselves we understand the risks, and decades later we discover we were wrong. The introduced strain outcompetes the native. The “harmless” cultivar escapes. The restoration project inadvertently destroys what it meant to save. Perhaps the real lesson isn’t just that we make mistakes, but that we consistently overestimate how much we understand and underestimate how much damage our interventions can cause.
As we head into late fall and our native plants begin their seasonal retreat, I find myself thinking about how these mistakes should guide us forward. Yes, we need humility about what we don’t know. Yes, we should question confident assurances about “harmless” cultivars or “improved” varieties. But the answer isn’t to retreat from the landscape—it’s to engage more thoughtfully. Plant more natives, but true natives. Create more habitat, but with local ecotypes. Do more restoration, but with species we actually understand. And with winter approaching, read more—dive into the scientific literature, explore botanical history, learn the fascinating stories behind our native plants. Don’t think that learning about plants has to be a chore. On the contrary, it can be an absolute delight! And yes, pokeweed is absolutely, definitely a perennial.
