Showing posts sorted by relevance for query mile a minute. Sort by date Show all posts
Showing posts sorted by relevance for query mile a minute. Sort by date Show all posts

Wednesday, July 05, 2017

Mile a Minute--A Wave Growing Across NJ's Countryside

You can spot it a mile away. Early summer, and already this annual, thorn-covered vine called Mile-a-Minute is rising like a wave along fencelines in New Jersey's countryside. Thus far, in my ramblings around Princeton, I have found only two tiny patches--at the Battlefield and along the driveway into Rogers Refuge--both of which have been knocked out the past two years. Is this sort of early intervention and annual followup worth it? The answer becomes abundantly clear just outside of town, halfway to Hopewell, where Mile-a-Minute vine is demonstrating just how much of a prickly menace it can be if not caught early.



It's a plant that seeks to be seen everywhere, and with all the other players on the plant scene. Here it is growing up a tree,

and sprawling over another invasive, garlic mustard.

Even those thistles with their prickly personalities aren't off-putting for a Mile-a-Minute vine.

It's said to have been an accidental introduction from eastern Asia via the nursery trade, originally gaining a foothold in York County, PA, in the 1930s and spreading from there.


Rampancy rules in this photo, as mile-a-minute swarms an autumn olive--a highly invasive shrub. When mile-a-minute's around, the curtain doesn't fall on other plants, but rises, in a wave of triangular leaves.

Here's Mile-a-Minute chasing the growth tip of a blackberry. Check back in a month to see who won the race.

Here, a privet's growing a prickly skirt.


Those pink flowers are Canada thistle, invader of many a garden bed, which is about to meet its match.

Long-time ubiquitous invasives, multiflora rose and Japanese honeysuckle, are joined by Mile-a-Minute.

You'd think perennial vines like wild grape would have a big advantage over an annual vine that has to spring anew from the soil every year, but Mile-a-Minute is looking up to the challenge.

Note the holes in the Mile-a-Minute leaves. Those are most likely from a weevil that was introduced as a biological control. The hope is that the weevil will become numerous enough, and consume enough triangular leaves to slow the wave of Mile-a-Minute engulfing the countryside.

Thus far, the Mile-a-Minute looks undeterred, growing over the slowly maturing fruits of wineberry,


and the pale stems of native black raspberry.




Beyond any ecological impact of such rampancy, it's interesting to reflect on the aesthetic and emotional impact of seeing a landscape being overrun by Mile-a-Minute. A healthy native prairie, for example, teaming with many species of grasses and wildflowers, all reaching for the sun with no inclination to crawl over one another, gives a feeling of striving, freedom, diversity, peaceful cohabitation, tolerance of one species for another. In contrast, a vine like Mile-a-Minute creates a smothering effect, a sense of clutter and thorny entanglement, a suppression of difference, an oppressive dependency that plays out as a punishment for any plant that dare reach a sturdy stem for the sky.

Tuesday, August 20, 2019

Invasive Mile-a-Minute Spreading at Princeton Battlefield


Ever find yourself caring deeply about something the rest of the world ignores? We all pick our battles, and here's a really good one for the Friends of Princeton Battlefield and/or our governing institutions to pick.

Princeton has been graced in many ways of which it is not even aware, and one of those is the up-to-now absence of Mile-a-Minute, a thorny annual vine that grows up and over everything if allowed. Gardeners beware. This one's particularly nasty, and though it has gained a foothold in nearby areas, I've encountered it in only two locations in Princeton. One location is the Princeton Battlefield. The other is on the gravel road in to Rogers Refuge. Each year I pull it out, but by the time I remember to do it, a few of the vines' little blue berries have matured, so the infestation has been growing.

Obviously, my efforts are not enough. The town of Princeton has fortunately hired the NJ Invasive Species Strike Team in recent years to treat invasions by new species, but the Battlefield is state owned, and because of a lack of intervention it is now serving as a seed source that will affect all Princetonians, and not only for Mile-a-Minute.



Another issue at the Princeton Battlefield is the massive invasion by porcelainberry--a vine that rivals kudzu in its capacity to sprawl over anything and everything. Its overwhelming presence may seem to dwarf the problem with Mile-a-Minute, yet it can also be seen as proof that we really need to catch these invasions early, before they get out of control. Porcelainberry is not only at the Battlefield, but is also dominating large areas all along the Stonybrook in Princeton.

Here are the copious berries produced by porcelainberry vines as they smother the flowering dogwoods planted in 1976 for the nation's bicentennial. The berries turn pretty colors--blue, purple, pink, or white--thus the name, and the original appeal of the plant. But the plant has escaped the usual checks and balances that otherwise sustain balance in nature.

Birds eat the berries of porcelainberry and Mile-a-Minute, thus the concern that what's allowed to grow at the Battlefield will impact the rest of Princeton.


The Friends of the Battlefield group, by the way, has been doing a great job knocking out big stands of bamboo around the Clark House during its annual workday in April. Look in the distance in the photo and you'll see an open field, with only a small remnant of bamboo back near the woods.

But bamboo doesn't spread by seed, and so poses no threat beyond the Battlefield's borders. Volunteer sessions can slow down porcelainberry and Mile-a-Minute a bit, but for any lasting benefit, we need to get some professional intervention. Maybe the Friends of the Battlefield could apply for a grant.

In the meantime, be on the lookout for its distinctive triangular leaf, put on some gloves, and pull it out.


Saturday, September 05, 2015

Mile-a-Minute Found at Princeton Battlefield


As if the massive invasion of porcelainberry, the "Kudzu of the North", at the Princeton Battlefield were not enough, I just discovered a patch of Mile-a-Minute there. This is, fortunately, only my second sighting of the prickly, fast-growing invasive in Princeton. The first sighting was in August of 2007, when I spotted it in a flower bed across Harrison Street from the Princeton Shopping Center.

For that first patch, it was relatively easy to contact the owner and convince her that it needed to be removed. The patch at the Battlefield is somewhat larger, about ten feet square, and has already produced berries that could be transported by birds to other locations. The next step is to go back with a sturdy pair of leather gloves and trash bags, and remove every last bit.

That Mile-a-Minute has a small foothold at the Battlefield suggests that it could have popped up most anywhere else in Princeton, so keep an eye out. The plant is an annual with distinct triangular leaves and a prickly stem reminiscent of our native tear-thumb. It should be pulled out and, if it has berries, placed in a garbage bag and put out for the trash. DO NOT put it in the compost, because the berries could then be spread.


It should be noted just how vulnerable we are to invasions of this sort. The Emerald Ash Borer's arrival in Princeton is a prime example. Accidentally imported to southeastern Michigan twenty years ago, it became established and therefore impossible to eradicate, because there was no "early detection, rapid response". Maintenance of the Battlefield grounds consists of mowing. Anything in the plant world beyond lawn requiring intervention is thus left to the chance interest and commitment of volunteers without a budget.




I happened to notice the Mile-a-Minute vine while checking the status of the ornamental flowering dogwoods planted long ago along the edges of the northern field at the Battlefield. I've been cutting the vines off, most years, but the porcelainberry is becoming increasingly dominant, smothering many of the dogwoods and other trees along the field's edge.

Here's a dramatic example, a dogwood barely visible beneath an oppressive cloak of porcelainberry.

On a planetary level, climate change was detected, but many with power to act have lacked a basic understanding of the consequences of delay. Here's where a naturalist's experience with invasives, or even a backyard gardener's experience with weeds like stiltgrass, mock strawberry, or ground ivy, can give insight into the importance of quick response. A ten foot patch of Mile-a-Minute seems minor, but without action, its berries will spread and the problem will quickly become too intimidating to dare act against. Bureaucracies do this all the time, as with Burmese pythons in the Everglades. Early warnings are ignored, and the problem doesn't become officially recognized as a problem until it's too big to solve.

Meanwhile, the vast lawn continues to be mowed, offering a superficial reassurance to passersby that the landscape is under control.

Sunday, September 19, 2021

Mile-a-Minute Spreading into Princeton

 One of the more noxious invasive plants that has been spreading across NJ is Mile-a-Minute. It's a prickly vine that, though an annual that must grow back from seed each spring, grows so fast that it can cover large areas of roadsides and field edges. Over the past several years, I've been knocking out small infestations at the Princeton Battlefield and near Rogers Refuge, but this year I'm finding new patches springing up around town.

Then, driving my daughter to MarketFair along Canal Pointe Blvd a week ago, I saw a massive infestation that surely is a major source of the seeds that birds are then spreading across Princeton. 

The vine has a distinctive triangular leaf. Berries are just beginning to ripen. If you encounter it, put some gloves on, pull it out and put it in the trash. Putting it in the compost would allow the seeds to spread. 




The infestation along Canal Pointe Blvd is behind 701 Carnegie Center Drive. In the aerial, you can see rows of solar panels over the parking lot. To the left of the solar panels is a big mowed lawn, and to the left of the lawn in the photo is the unmowed land upon which the Mile a Minute is growing. My friend Peter researched the owner, which on the deed appears to be "BXP Carnegie Owner, LLC%G". The land has a farm easement, so is only valued at $39,000, which means the owner is paying next to no taxes to hold very valuable property, meanwhile expediting the spread of Mile a Minute and the associated nuisance it will cause. 

It's hard to photograph the cocktail of invasive species at the site. The white flowers are of white snakeroot, a native wildflower, which is besieged by a layer cake of stiltgrass, porcelainberry, and Mile a Minute climbing on top of it all. 

Further down the road is a series of trees damaged, perhaps by a small tornado or similar localized intense winds as the remains of Hurricane Ida came through on Sept. 1. Similar damage to trees was seen in Princeton Battlefield, where a row of mature white pines along the edge of the field was decapitated.

What we're seeing is the increasing impact of plants out of place (species that turn invasive after being introduced from other continents) and carbon out of place (carbon fuels extracted from underground that we burn, thereby releasing additional carbon dioxide into the atmosphere). Our machines have increased global warming CO2 by a whopping 50% over pre-industrial levels thus far. This year has felt like a radicalization of both invasive species and climate change. 

Saturday, October 03, 2015

Mile-a-Minute Strikes Again


The second sighting of Mile-a-Minute, a.k.a. Persicaria perfoliata--Princeton's new invasive species with triangular leaves, sharp spines, and speedy growth--came two weeks ago during a tour for a visiting friend of my various habitat restoration projects around town.

First stop was Rogers Refuge, to see Princeton's improbable marsh, nestled between the Institute Woods and the Stony Brook, where birds and birders congregate,

and wild rice thrives. Runoff and seepage from the slopes of Institute Woods are augmented by water pumped from the Stony Brook to keep the marsh wet through summer droughts. For anyone seeking auspicious partnerships between people and nature, between private, public and nonprofit, will find it here. The land is owned by the American Water Company, which pays for the electricity to run the pump, which in turn is maintained by the municipality. The Friends of Rogers Refuge, not quite a nonprofit but an official volunteer organization nonetheless, is the entity that cares most deeply about the marsh and the birds it provides habitat for, and so pays the attention necessary to make sure the pump and everything else is running smoothly.

But I was talking not about functioning habitats and symbiotic institutional relationships, but about the new invasive threat on the block, which we encountered on the drive back out of the refuge.


There, climbing up a big blob of porcelainberry surrounding a telephone pole, was the Mile-a-Minute. It was a smaller patch than I had found at the Princeton Battlefield several weeks prior, but that two patches have now been found suggests that this invasive has gotten a foothold somewhere in the Princeton area, and birds are spreading the seeds across town.

This patch, too, found its way into a plastic bag that was sealed and will be put out for trash collection, lest its seeds spread.



The gravel driveway into Rogers Refuge, by the way, is exhibit A of how invasives can take over a landscape and render it inedible to wildlife. The original alteration of hydrology to build the road discouraged natives and made perfect habitat for invasive species. Japanese stiltgrass lines the edges.

Here, the "grass on stilts" reaches up towards another invasive that's much better at climbing, porcelainberry.

That moundy appearance is porcelainberry vine growing over everything. As stiltgrass coats the ground of our forests and displaces the turfgrass in our lawns, porcelainberry expands its elevated, kudzu-like dominance across Princeton.

Asian photinia, note the unusually obovate leaves (wider towards the tip) whose capacity to take over the forest understory was first demonstrated at Mountain Lakes preserve, is also having a good year.

Even if this invasive multiflora rose is succumbing to rose rosette disease, another invasive, Japanese honeysuckle, comes along to climb over it.



This sign, from back in the '70s when invasives must have seemed a minor annoyance, says not to take or injure any plants.



But some of those rules that seemed to make sense in the 1970s make no sense now. I made sure to return to take one plant, that prickly Mile-a-Minute.

You, too, can be a plant keeper. Keep an eye out for Mile-a-Minute, and contact me if you see it.



Saturday, August 01, 2020

Mile-a-Minute Vine in Princeton



Each year I conduct a solo campaign to keep the highly invasive weed Mile-a-Minute out of Princeton. It's a prickly annual vine that grows each year from berries produced the year before. Knock it out before it produces berries, and eventually there will be no berries to sprout. Otherwise, the infestation will grow and birds will spread the berries across all of Princeton, to spring up in backyards and vex homeowners with its thorns and rampant growth.

I know of two infestations--one at the Princeton Battlefield, the other down off West Drive on the gravel road to Rogers Refuge. Yesterday, passing by Princeton Battlefield, I stopped to uproot what Mile-a-Minute I could find and leave it on the lawn to dry in the sun. Like most annual plants, it has whimpy roots and can easily be pulled, wearing a good pair of gloves.



Princeton Battlefield has a remarkable history, which makes it all the more remarkable how ahistoric the landscaping is. Non-native turf is surrounded by giant kudzu-like topiaries of non-native porcelainberry vine growing over the native dogwoods that were proudly planted for the 1976 bicentennial. There's little hint of what the Clark Farm looked like on that fateful day in January of 1777. The lack of botanical context doesn't fit with the people and era the Battlefield is meant to celebrate. Plants were important to George Washington and other leaders of his time. They were farmers. It's not coincidence that the United States Botanic Garden was built to stand next to the U.S. Capitol building. What grew upon the land mattered back then. They didn't mow the lawn and think their work done.

Seeing a landscape so invaded and out of balance, I sometimes imagine a hospital with no doctors or nurses, only custodians dedicated to keeping the place clean. The patients are on their own, unless a volunteer doctor happens by to treat some localized infection. That's the situation in the vast majority of our landscapes, cared for by custodians armed with raucous mowers and leaf blowers, oblivious to the complexities of nature and its needs. 

In the meantime, I pull the Mile-a-Minute, trim back some small portion of the porcelainberry vines so the dogwoods might live another year, and wonder at the world's disconnect with nature.

The two photos show 1) porcelainberry vines overwhelming a dogwood tree, and 2) another sea of porcelainberry in which only the similarly invasive Canada thistle can manage to lift its pink flowers above the swarm.

Tuesday, October 03, 2017

Wanted: A Few Good Herbivores

If you encounter a book or article that claims that, surprise!, invasive species aren't such a big problem after all (a few were written over the past decade), you'll probably find no mention of herbivory. They'll say that invasive plants are being falsely maligned, because actually they do wonderful things, like provide berries and nectar for wildlife. But it's to the plant's advantage to have its flowers visited and its berries consumed. What the plant doesn't "want" is to be eaten, and therein lies the problem with plants that become invasive. For whatever reason, be it an invasive's chemical defenses or ingrained dietary habits, the wildlife tend not to eat them.

Nature depends on consumption to keep things in balance. We love nature for its beauty and variety, but behind the scenes there's a whole lot of mastication going on. Take away predators and the deer population explodes. Introduce a new plant that the wildlife won't eat, and there's potential for that species to make habitat less and less edible as it displaces the natives. To fill this void in consumption, people have had to play the role of herbivores. What we do at Herrontown Woods, as we cut down dense groves of winged euonymus and other nonnative invasive shrubs, is to play the role of the missing herbivores, using our loppers for teeth.

There's some pleasure in the work--pleasing vistas created, serendipitous discoveries. But all things being equal, it would really be nice if the resident wildlife could show some flexibility in food preferences and fill the void in consumption. Invasives, after all, represent a huge, untapped food source for any animal willing and able to broaden its palette.

Given how much work it would be for humans to play the role of herbivores in the forest, any evidence of wildlife gaining an appetite for invasive plants stirs some hopefulness.


For instance, an invasive honeysuckle shrub was recently found stripped of its leaves. A closer look revealed something had been hard at work, its mandibles outshining our loppers: the caterpillar of a snowberry clearwing moth, also known as the "hummingbird moth" or "flying lobster", for its capacity to hover in front of flowers as it sips their nectar. Maybe if we had more summer wildflowers for the adult moths to feed from, their caterpillars would help control the populations of bush honeysuckle in Princeton's preserves. Nice to think, anyway.


And what's this orange plant growing on a dense expanse of invasive mugwort that grows as a monoculture along the gas pipeline right of way in Herrontown Woods? Dodder is a parasitic plant with little capacity to gather energy from the sun. Instead, it wraps itself around other plants and sucks out their juices.

Usually, its impact is small, but this must have been a particularly good year, because a sizeable patch of mugwort was sucked dry.

If only we could get the dodder (genus Cuscate) to preferentially neutralize the mugwort all along the right of way, some diversity might return. Again, a nice thought and tall order.

A new invasive trying to gain a foothold in Princeton is mile-a-minute vine, with a distinctive triangular leaf, a prickly stem, and a growth habit to match its name. Another post shows how invasive this annual vine can be , on farms just outside of town. Fortunately, after weeding out a small population back in 2007, I know of only two patches currently growing in Princeton, still small enough to control and hopefully eliminate altogether.

One's at the Princeton Battlefield. This year's growth was pulled out in early summer, and when checked in late August, the patch had only managed to produce a few leaves, all of which were being very effectively munched on by a weevil intentionally introduced to the U.S. to bring this rampant new species under control.

Ah, I concluded, to control mile-a-minute vine, simply reduce the patch in early summer, leaving enough for the weevils to sustain their population on. Their appetites appeared to be sufficient to prevent any flowering or fruiting that could lead to the patch spreading elsewhere.

Nice concept, but it wasn't working at the other site, down along the driveway into Rogers Refuge, where the vine had sprung back up, flowered and fruited, undeterred by the minor nibblings of the weevil. That patch had to again be pulled out by hand.


Another discovery was the work of the Ailanthus webworm moth, which had completely defoliated a young tree of heaven near the parking lot of Herrontown Woods. The moth, like the tree, is an introduced species.

If you have flowers like boneset growing in your backyard, you may be helping the adult moths to prosper.

Here again, though, the larvae have thus far been seen only on very young trees, with larger ones largely left untouched.

These are glimmers of hope, sprinkled across Princeton. It will take some concerted mastication by as yet unnamed herbivores to stem the tide of rapidly spreading species like porcelainberry, callery pear and stiltgrass--a giant uneaten salad that grows by the year. A little salt and pepper, perhaps?




Sunday, May 21, 2017

Invasive Plant Species in Princeton


This Monday, May 22 at 7pm, the Princeton Public Library will host a presentation on invasive species in Princeton by Mike van Clef, of the NJ Invasive Species Strike Team. There will also be representatives of FOPOS and DR Greenway participating. Princeton municipality hired Mike to develop a report on invasive species in Princeton preserves, and in 2016 he and two interns worked through the summer on invasive species control. Because of the massiveness of the problem, they focused on emerging species--those whose populations are still small enough that a summer's worth of control would make a difference. 

We may look back on 2016 as a pivotal year, when the town began investing in invasive species management, much as 2000 marked the beginning of professional deer management in town. 

Although it may sound self-congratulatory, another important date in Princeton's history of invasive species management would be 2006, when the Friends of Princeton Open Space hired me as their first Natural Resources Manager. 

When I arrived in town in 2003 on the coattails of my wife's appointment to the Princeton University faculty, a couple things quickly became obvious. First, Princeton had done wonderful work preserving land for open space. Second, the open space itself needed a lot of work. Though the trees in Princeton's woodlands were mostly native, the understory vegetation was often dominated by nonnative, invasive plants. Stiltgrass, honeysuckle and privet, to name but a few, had filled the void created long ago when the diverse native understory had been plowed under, back in Princeton's agricultural era. In the decades since, the native trees had rebounded, but the understory had either not come back, or succumbed to heavy browsing pressure from deer.

Because wildlife tend not to eat the leaves of nonnative plants, their proliferation in preserves renders the habitat largely inedible. Yes, birds can eat the berries of nonnative shrubs like honeysuckle, but if the insects and other wildlife aren't eating the leaves, then much less of the solar energy captured in the plants can move up the food chain. 

I proceeded to make the case that Princeton could expand its effective acreage of open space through management for native species. As most readers know, I've been leading workdays and nature walks ever since, for six years as an employee of FOPOS, and more recently as president of the Friends of Herrontown Woods (FOHW). Highly motivated volunteers like Tim Patrick-Miller and Andrew Thornton, and more recently Kurt and Sally Tazelaar at Herrontown Woods, have had a positive impact over time. Meanwhile, FOPOS has sustained its Natural Resources Manager position--having just hired the fourth to hold that position--and continues to do invasive species removal at Mountain Lakes Preserve. After so many years of nonprofit, largely volunteer efforts, to finally get municipal support through Mike's crew this past summer was a real boost that we hope will continue.  

It's important to note that Mike van Clef's study of invasive species in Princeton is limited to parks and preserves owned or managed by the town. There are large expanses of open space owned by the state (Princeton Battlefield and DR Canal) and by the Institute for Advanced Study (the 600 acre Institute Woods). Portions of the Battlefield and the DR Canal are being overrun by porcelainberry (in photo), which barely registers in Mike's survey, and mile-a-minute vine is beginning to show up there as well. I've been trying to help fill a void in management, co-leading workdays at the Battlefield and, in the proactive "early detection, rapid response" tradition, dealing with two small infestations of Mile-a-Minute in town before they become unmanageable. Another nonnative plant that's spreading rapidly, both in people's yards and in nature preserves, is lesser celandine (a.k.a. fig buttercup). It can only be controlled in the spring, long before summer interns begin work. Ideally, a town-wide coordination to manage invasive species would be developed.

The town's investment in invasive species control comes at a critical time. With the emerald ash borer (another highly invasive introduced species) poised to decimate Princeton's most numerous native tree, large gaps will be created in our forest canopy, allowing light to penetrate to the understory. Princeton's long investment in deer culling has allowed native shrubs like spicebush to make a comeback, but in many woodlands, the understory is dominated by nonnative shrubs and stiltgrass. Wildlife have evolved over millenia to eat native species. It's a question of whether edible natives will capture that extra sunlight in the understory, or the privet, winged euonymus, honeysuckle, barberry and Photinia. The foodchain depends on our intervention.

The primary argument for habitat management remains that, by improving the quality of habitat, Princeton effectively increases the functional acreage of open space. This is true not only for wildlife but also for people. Controlling invasive species also makes the human experience in preserves more rewarding. As we've cut down invasive shrubs at Herrontown Woods, we've not only made more sunlight, water and nutrients available for native species to prosper, but also have opened up pleasing vistas and made the woods more navigable. 

The problem of invasive plants may seem overwhelming, but we can take our inspiration from the deer, who transform landscapes through the cumulative impact of browsing here, there, and everywhere, one mouthful at a time. The pioneers, too, thought the continent too vast to ever tame. Though their goal wasn't exactly to increase native plant diversity, they showed how steady effort makes a difference over time. Ideally, professionals will complement existing volunteer efforts, and the locals who know the preserves best will help steer the professionals' interventions. 


At Monday's presentation, there will also be discussion of a list of invasive species that people are being discouraged from planting. It's a very long list, and I wish it could better reflect the broad spectrum of invasive behavior we see in the field. One reason the list is so long is that, though many of the species on the list may not be found spreading into Princeton's nature preserves, history shows that invasive behavior in nonnative species may not become manifest until many decades after they've been introduced. Chinese silver grass (Miscanthus sinensis) is a case in point. Though it has yet to spread to Princeton's Tusculum meadows, it is now posing a big problem for meadows at Duke Farms up in Hillsborough. The flyer for the library event includes a photo of butterfly bush, which I've never observed exhibiting invasive behavior. Monday's presentation may help put local observations in a broader context.

Update: Full house for the program! Good to see.