Showing posts sorted by relevance for query celandine. Sort by date Show all posts
Showing posts sorted by relevance for query celandine. Sort by date Show all posts

Thursday, March 11, 2021

Be On Guard for Lesser Celandine

(This post is from 2021. Click here for more recent posts about nature.)

From backyards to front yards to curbsides to parks and nature preserves, a small invasive flower is on the march. Dominating the landscape in early spring with its yellow blooms, it turns March into LOOK AT ME, ME, ME!, because that's all you will see when lesser celandine coats the ground. Just to hoodwink homeowners, the name "lesser celandine" has sometimes been supplanted by the name "fig buttercup," but it's all the same plant, whose latin name is Ficaria verna

My posts about the plant date back to 2007, when I heard people mistakenly calling it "marsh marigold," which it most emphatically is not. Back then, lesser celandine was most entrenched at Pettoranello Gardens and rapidly spreading downstream into Mountain Lakes. Hopefully, when Princeton hires an open space manager, a more coordinated effort can be launched to reduce the plant's spread and protect areas not yet infested. Homeowners tend to like the plant at first, then become appalled as it begins taking over the yard and spreading to the neighbors'. 

Use herbicides on lesser celandine? The nature of good and evil.

Those who care enough about their yards and the local ecology to want to stop the plant's spread may also feel qualms about using herbicides, which are the only practical means of control. Removal by digging is cumbersome, time-consuming, and adds unnecessary weight and bulk to your trash can. I encourage people to think of herbicides for nature the same way we think of medicines for people. We know all medicines have some level of toxicity, but we use them in a minimal and targeted way to protect our health. Doesn't nature deserve the same sort of intelligent intervention? It's important to make a distinction between spot spraying for lesser celandine and the blanket application of pesticides and chemical fertilizers on lawns. Glyphosate and Roundup are not synonymous. There are wetland-safe forms of glyphosate available online, not made by Monsanto. If treating lesser celandine that has invaded lawns, use an herbicide that is selective for broadleaf plants so that the grass survives.

While avoiding blanket condemnations of herbicides, I also like to avoid thinking of invasive species as "bad plants." Like so many of the problems that plague us, they are "too much of a good thing." Unfortunately, though it might be tempting to keep a few lesser celandines in the yard, its super aggressive behavior makes that very risky. Best to eliminate it altogether. Winter aconite, on the other hand, is a nonnative that looks a lot like lesser celandine but has not to my knowledge spread into natural areas.

Selected past posts:

2019: Fig Buttercup--Little Flower, Big Problem - Photos of fig buttercup's (lesser celandine's) spread, along with a discussion of why this invasive species creates more problems than other common invasives.

2018: A World Paved With Fig Buttercup? - Lesser celandine's other common name is fig buttercup. This post documents in photos and text the astonishing spread of this plant in the Mountain Avenue neighborhood.

2017: Winter Aconite and Fig Buttercup--Related Flowers, Contrasting Behaviors - These two early blooming yellow flowers look very similar, but behave very differently.

2016: Letter On Lesser Celandine Strikes a Nerve - a letter in the Town Topics that got quite a response

2016: Alert, Monitoring for Lesser Celandine - This post includes links to treatment options.

2015: Marsh Marigold vs. Lesser Celandine - Lesser celandine is frequently mistaken for the native marsh marigold, which is a larger plant and very, very rarely seen.

2013: Will the Real Marsh Marigold Please Stand Up--a Confusion of Yellows - Some photos help distinguish lesser celandine from marsh marigold, dandelion, and celandine poppy.

2007: Pretty, but... - My earliest post on lesser celandine.

Friday, April 15, 2022

Lesser Celandine Alert!

It's time for the annual call to action to prevent lesser celandine from taking over all of Princeton. Also called fig buttercup, it's a highly invasive nonnative plant that is spreading rapidly, yard to yard and into parks and nature preserves, where it degrades habitat for wildlife. It thrives on homeowners' indifference and inaction, so I've been doing what I can, urging town officials to defend our parks and preserves, urging homeowners to take action in their own yards, explaining that herbicides are not anti-nature if they are used selectively and medicinally. My letter to the Town Topics and other local publications starts like this:

Blooming in many people’s yards right now is a small yellow flower that, upon closer inspection, proves not to be a dandelion. Variously called lesser celandine or fig buttercup, its radical invasiveness triggers a predictable progression of emotions in the homeowner. Delight at its pretty flower soon turns to alarm as year by year it takes over the yard, spreading through flower beds, across lawns and into neighboring properties. What may start as a few scattered, harmless-seeming clumps quickly becomes the equivalent of a rash upon the landscape. Unlike the dandelion, lesser celandine also spreads into nature preserves. Poisonous to wildlife, it forms thick stands reminiscent of pavement. Over time, our nature preserves become less and less edible to the wildlife they were meant to support. Native diversity shifts towards non-native monoculture.

Below are some photos to help with identification, and here is a link that includes suggested means of stopping it from taking over your yard. Though the link says only to spray through early April, I'd suggest that spraying is helpful for as long as its leaves are green. Lesser celandine is a spring ephemeral, meaning that it comes up early, then dies back in June, going dormant until the next spring. Gardeners who like to dig up plants of this or that to give to friends should be aware that, if their yards have been invaded by lesser celandine, some of it may hitchhike in whatever plants they dig up later in the season to give away. They may unwittingly be giving a fellow gardener the beginnings of a major headache.

Lesser celandine is poisonous, and yet some websites declare it edible and offer recipes. Why the contradiction? Apparently, lesser celandine accumulates toxins later in the spring. The toxins break down during cooking or after drying. Still, one takes one's chances trying to eat it, and, alas, wildlife don't cook.

I've seen bees collecting pollen and nectar from the flowers, which is all fine and good, but this doesn't compensate for the inedibility of the leaves. The invasion of our lands by nonnative plants that wildlife don't eat essentially shrinks the acreage of functional habitat in Princeton, even though a great deal of open space has been preserved. Thus the need for management.

Given that some areas of Princeton have been overrun by lesser celandine, it's important to defend those areas that have not, by closely monitoring and spot spraying where the plant is just starting to move in. Invasions begin with just a few plants here and there. An absolute minimum of herbicide is needed to easily defend these areas. Lesser celandine can easily be distinguished from dandelion. Walk the grounds before the grass gets mowed in the spring and while the plant is blooming. For lawns, a product like Weed B Gone works. For other areas, a 2% solution of glyphosate does the trick. Since glyphosate can take a week to show visible effect on the plant, it's best to spray early in the spring so that there's time to see results and spray any areas missed. For those near wetlands, wetland-safe formulations of glyphosate are available, so Roundup is not the only option.

In terms of aesthetics, lesser celandine's dense, exclusionary growth does to the landscape what people badly afflicted with narcissism do to social situations. A woodland that once hosted a diversity of native wildflowers becomes, when overwhelmed by lesser celandine, one species' declaration of Me! Me! Me! 

Here's what it looks like up close.

Here's an example of the blotchy appearance an early invasion creates on a lawn. These blotches expand until the whole yard is coated.

The closest lookalike in the lawn is the violet, whose leaves are darker, more curled, and more toothed along the edges. 





Monday, April 10, 2023

Protecting Areas of Princeton Not Yet Infested with Lesser Celandine

Each spring I send out an alert about the spread of a hyper-invasive plant called lesser celandine (also called fig buttercup, or Ficaria verna). Through website posts, letters to the editor, and social media like facebook and nextdoor, I've urged people to take action in their yards to prevent lesser celandine from taking over. The latest effort was a writeup in TapIntoPrinceton

Some weeds, like dandelions, proliferate only in lawns and gardens and pose no threat to natural areas. But lesser celandine spreads from lawn to garden to nature preserve, growing in sun or shade, lowland or upland. If left to grow, one plant will ultimately multiply to pave the landscape. Pettoranello Gardens, Marquand Park, Rogers Refuge, Mountain Lakes--these are some of the preserves with rampant infestations. As it displaces native flora, this poisonous plant makes our nature preserves less edible for wildlife.

It can be easy to despair, but the good news is that there are many yards, parks and preserves where lesser celandine is just now starting to invade, and could be easily controlled.
This is what lesser celandine looks like when it first moves in to a new area--a dense mound of leaves with a few flowers in late March and early April.
Westminster Choir College's huge lawn has only five or six of these clumps. It could easily be treated with a little spritz of weed killer (see below for some of the rationale for using herbicide). Five minutes of strategic intervention, and one's work would be done until following up with the same monitoring and treatment next year. 
Here's a sprinkling of just a few plants in Smoyer Park, all in a line, demonstrating how the weed is spread by rainwater that runs along the bottom of this detention basin. Again, this is a very quick job with minimal use of herbicide, with even less needed the following year. 
Here's a big clump next to the school garden at Community Park elementary. If they wanted to be organic about it, they could try covering it with cardboard and thick mulch for two growing seasons and hope the roots die off. Or they could dig it up very carefully and thoroughly, and throw all the plants and associated dirt in the trash.

But that doesn't deal with the clumps of lesser celandine that have spread to the CP lawn nearby. You can't dig up or mulch a lawn, and other alternatives to standard herbicides have not been proven to kill the roots, so you pretty much have to spot spray the lawn with weed killer, or else allow a poisonous plant to take over the very school grounds that a town-wide initiative is seeking to make more edible.

There's a similar dilemma at tiny Barbara Boggs Sigmund Park, where a patch of lesser celandine is spreading across the lawn for lack of strategic intervention. If not treated, that patch will begin to spread downhill, infesting neighbors' yards. 
It's common for one neighbor to let an early invasion expand, unaware of what's going on. This patch is at the back of a property that the owner seldom visits.

Here's another patch spilling under the fence and out towards the street from an infested backyard. This is the only infestation on this particular block, and could be prevented from spreading.


I told the caretaker at Nassau Arms apartment buildings about an early invasion on that property, and he promptly dug it up. Hopefully the diggings went into the trash so that they don't spread elsewhere. We'll have to wait until next year to see how effective it is, but at least there was a quick response. 

What the dramatic and largely hopeless invasions at Pettoranello Gardens and elsewhere can teach us is to treasure and protect those parts of town that can still be spared. To make such protection time- and cost-effective, we must begin by reassessing our blanket condemnation of herbicides as poisons. We don't condemn all medicines as poisons, but instead manage their varied toxicities by applying them selectively and minimizing dose. The same applies to managing a park or one's yard. 

The pandemic dramatically taught us that what each of us does, intentionally or not, affects others. The lesser celandine in one yard or park can easily spread to neighboring areas. This is both humbling and empowering. It tells us that what we do matters beyond the borders of our lives and our yards. Strategic action by the town,  businesses, and residents can stop these infestations while they're still easy to stop. 

Sunday, February 26, 2017

Winter Aconite and Fig Buttercup (lesser celandine)--Related Flowers, Contrasting Behaviors

Both of these non-native wildflowers are in the family Ranunculaceae. Both bloom early and have pretty yellow flowers. While one appears to be modest and highly local in its spread, the other spreads so quickly across yards and into neighbors' yards and floodplains as to pose a threat to gardens and natural areas alike.


Here's winter aconite (Eranthis hyemalis) opening up a week ago in my garden, a legacy from the previous owner. Its modest spread is easily contained. I've never seen it spreading into nature preserves. Note the leaf shape, which distinguishes it from the related wildflower below.

Update: For comparison, here is one of the first blooms of lesser celandine in 2021, on March 30. Note the shape of the leaves, which are "entire" rather than lobed. Just to confuse things, lesser celandine is also called fig buttercup, and its latin name Ranunculus ficaria has apparently changed to Ficaria verna

People think lesser celandine is pretty, transplant it to their gardens, then begin having regrets as it spreads uncontrollably to dominate their gardens and yards. If you are one of the distraught gardeners wishing you didn't have this flower, and not wanting to impose its spread on the rest of the neighborhood, late winter is the time to deal with it. 

Other posts on this subject can be found on this website by typing "celandine" into the search box. A post called "Will the real lesser celandine please stand up--a confusion of yellows" helps with identification.

Though I'm no fan of herbicide, that tends to be the only workable option in the majority of cases. I'm no expert on herbicides, but have been told that for lawns, a broadleaf herbicide like Weed Be Gone is effective. For flower beds, a 2% formulation of glyphosate (Roundup or equivalent) works well. Monsanto doesn't hold the patent any longer on glyphosate, so it's possible to buy if from other companies on the internet. I use a wetland-safe formulation, but for most yards, away from wetlands, some spot spraying with Roundup or equivalent should be okay. The plant itself is poisonous to wildlife. 

There have been other proposed means of killing the plant: 
Mulch
If you blanket the whole infestation thoroughly with mulch, e.g. a layer of cardboard covered leaves or hay or woodchips, it might kill the lesser celandine if you mulch as soon as the plants leaf out in late winter. Chances are, you won't cover it soon enough, or you'll miss some spots, and the lesser celandine will benefit next year from the fertilizer in the mulch. 

Vinegar/salts/detergent
This concoction has shown up on the internet: 1 gal white vinegar, 2 cups Epsom salts, 1/4 cup Dawn dishwashing detergent in a hand held 2 gal pump sprayer. Spray in bright sun on a windless day.
But I couldn't find evidence that it has been carefully tested, nor that it would kill the roots. If the roots survive, the plant will be back next year. The concoction contains an acid, and the salts are made of magnesium and sulphates. These may or may not be harmful to the soil if used to excess. 

Thursday, April 28, 2016

Letter On Lesser Celandine Strikes a Nerve

A letter I sent recently to the Town Topics newspaper in Princeton struck a nerve. It was about a pretty but very aggressively spreading nonnative flower called lesser celandine. One reader, I was told, even printed the letter out and distributed it to her neighbors, in hopes that they would take a look in their yards, and take action before the plant took over the neighborhood's flower gardens and lawns. My next post on the subject was going to be a critique of You Bet Your Garden, the widely heard radio program, whose website posting on lesser celandine is full of misinformation. It's both fascinating and alarming to see how even a supposedly authoritative source like Mike McGrath can end up spouting nonsense, which then spreads to listeners, one of whom in turn further spread McGrath's misinformation in a response to my letter published in the Town Topics this week. As with climate change, the intimidating reality of invasive species has led many people to seek refuge in denial of either the problem or the solution, or both.

In the meantime, below is the letter I wrote:


If you’ve noticed a little yellow flower starting to take over your lawn and garden, you aren’t alone. Appreciation soon turns to distress as the plant spreads to become a form of green pavement, outcompeting other plants, then leaving the ground bare when it dies back in early summer. It has lots of names—lesser celandine, fig buttercup, figroot because of its fig-shaped underground tubers, or the scientific name Ficaria verna.

Like many introduced species, it gains competitive advantage by being inedible to the local wildlife. Along with nonnative shrubs that wildlife also avoid, like honeysuckle, winged euonymus, privet and multiflora rose, lesser celandine prevents solar energy from moving up the foodchain from plants to insects to birds. This foiling of natural processes effectively shrinks the acreage of functional open space Princeton has worked so hard to preserve.

The most dramatic example of this plant’s dominance locally is in Pettoranello Gardens, from where it has spread downstream into Mountain Lakes Preserve. That situation is beyond control, but in homeowners yards, and many local parks and preserves, early detection and treatment can nip invasions in the bud. I’ve been encouraging homeowners and the town rec. department to take this work seriously, because one small infestation can quickly spread to affect downhill neighbors, parks and preserves. Effective treatments can be found online, but typically consist of using 2% glyphosate, the active ingredient in products like Roundup, the wetland-safe Rodeo, and other similar formulations.

As with the abuse of antibiotics by the meat industry, glyphosate is now vastly overused to grow bio-engineered corn and soybeans. That abuse has in part driven a demonization of herbicides in general. But just as antibiotics remain a critical medicine, various herbicides remain a critical means of dealing with invasive plants. Personally, my avoidance of herbicides is nearly total, but in the case of lesser celandine, with its tuberous roots, no other approach is practical. Only if there are just a few plants can one dig them out, bag them up and throw them in the trash, not the compost.

Adding to the distress of these radical transformations of our landscapes is a strange narrative that is showing up in places like the New York Times and the radio show You Bet Your Garden. Through a denial of both the problem and the solution, reminiscent of climate change, it claims that we should learn to love invasive species, and hate those who dare to take action against them.

This view cheats us of the deep satisfaction of identifying a problem and working together to solve it. This past weekend, as part of my work for Friends of Herrontown Woods, I was able to convince a couple neighbors of the preserve to treat their lesser celandine. By doing so, they will not only spare their own yards but also the stream just down the hill.

As a bonus, I got to meet some new neighbors. By taking our local nature’s problems seriously, we also build community.

Thursday, March 31, 2016

Alert: Monitoring for Lesser Celandine

Memory was finally jogged that this is the time of year to be scouting Princeton's natural areas for the dreaded Ficaria verna, a.k.a. fig buttercup, or lesser celandine. Dreaded because it has an alluring yellow flower that makes one want to leave it be when it starts showing up in the yard or local preserves, but then quietly takes over, paving whole valleys. Pettoranello Gardens is carpeted with the plant. In Durham, NC, I once tracked an infestation upstream to a homeowner's yard. He was greatly relieved to find out what plant had taken over his garden, and proceeded over the next several years to completely eliminate it. Unfortunately, by then the plant had spread far downstream and would transform a whole watershed, from one small infestation in someone's yard. He was, however, able to remove some he had put in his son's yard elsewhere in town, before it had a chance to spread downstream. This is why it's so important to get the word out about these highly deceptive species.

When I was working at Mountain Lakes, I'd walk the valley leading down from Stuart School, searching for any small patches that could be eradicated before they expanded beyond remedy. It's satisfying to be able to nip invasions in the bud. Now that my focus is Herrontown Woods, the spring ritual is playing out there. Yesterday's walk yielded no sightings until the very end, when I checked the pawpaw patch we planted New Year's weekend, and headed back through the woods towards the parking lot. There, right where the groundwater seeps out of the ground in what originally may have been a primitive septic system, was a patch of lesser celandine. Already, it has spread down the ditch about fifty feet, but is still of a size that we can eradicate it before it spreads down the valley, beyond control.


Control options can be found at this link. A comparison of lesser celandine with other yellow spring flowers, such as marsh marigold and celandine poppy, can be found here. If possible, avoid hiking through an area with lesser celandine--there's a risk of inadvertently spreading it into new areas in the treads of your shoes.

Monday, May 04, 2015

Marsh Marigold vs. Lesser Celandine


Yellow is not so mellow in April and May, when one of the uber-invasives, lesser celandine, carpets many floodplains and spreads across lawns. The now massive population at Pettoranello Gardens no doubt started as a clump here and there. In an example of how the management of one park can affect others, the lesser celandine at Pettoranello Gardens has since spread downstream to infest the lower portion of Mountain Lakes preserve, where it is displacing the native species that have long filled a similar niche in a less domineering way.

The lesser celandine is often confused with the native marsh marigold, which I've never seen growing naturally in Princeton. To show how they can be distinguished, I planted some marsh marigold (bought at Pinelands Nursery) down near the stream at Pettoranello Gardens, in a spot that would benefit from the stream's steady water supply but not be swept away by floods. The location proved a good choice, because it has survived many years now. You can see it at the top of the photo, taller and with larger leaves than the lesser celandine in the lower half of the photo. More marsh marigold has been thriving at the Princeton High School ecolab wetland, which too has the stable presence of moisture the native requires.


Ecologically, the only good news I know about lesser celandine is that there are still some parts of Princeton that have not been colonized by it. But those locations must be monitored each year to catch invasions before they get out of hand. To take a for instance, in Community Park North, which is upstream of Pettoranello Gardens, I found only two small patches that could easily be treated to prevent spread. The plant likely got there on the shoes of someone hiking on a muddy day.


Monday, April 22, 2013

Will the Real Marsh Marigold Please Stand Up--a Confusion of Yellows


A lot of people call this flower "marsh marigold". It's not. Notice the leaves stay close to the ground, and the small flowers have many petals. This plant is actually Lesser Celandine, a pretty but highly invasive exotic plant that will spread across lawns and coat floodplains in what looks like green pavement. I found this one specimen in my yard, and because there was only one, I was able to dig it up, hopefully before any seeds were produced, put it in a plastic bag, and threw it in the trash, not the compost.

(Update: Most homeowners don't notice lesser celandine, also called fig buttercup or Ficaria verna, until there are too many to dig. Digging also requires getting every last tuber in the roots. Oftentimes, the only practical option is to use a targeted dose of herbicide. Though herbicides are demonized due to their overuse in agriculture, the selective use of low-toxicity herbicides is an important part of invasive species control, just as low-toxicity medicines are selectively used in medicine. I use a 2% wetland-safe version of glyphosate, which can be bought from companies other than Monsanto.)


The real marsh marigold, shown here, is a native with five-petaled flowers, stands more upright, and is so rare that I've only seen it growing wild once in my life. These particular plants are in my backyard, purchased from Pinelands Nursery in Columbus, NJ. I also planted some at the Princeton High School Ecolab Wetland that are in full bloom right now.

The flower and leaf of marsh marigold (Caltha palustris) are on the left, with lesser celandaine (Ranunculus ficaria) on the right.


Dandelions blooming now can make it harder to tell if you have lesser celandine in your yard.

Adding to the confusion of yellow this time of year is the Celandine Poppy (Stylophorum diphyllum), a native in the poppy family that was common in the University of Michigan arboretum, but seldom seen elsewhere. A friend in Princeton gave me some, and it has seeded into the flower bed of my backyard. Like the marsh marigold, its rareness in the field bears no relation to its willingness to grow when planted in the backyard.

Thursday, April 21, 2016

Native Plant Event at Whole Earth Center


On Sunday, May 1, 11-2pm, the Whole Earth Center in Princeton will have a native plant shindig. That's what Alex Levine, Whole Earth's master artisan of deli cuisine calls it. The official title is "Landscaping With Native Plants", and will feature native plants for sale and free advice from some of us landscaper, native plant seller, naturalist types. There's more info and a pretty photo of Alex's wildflower garden at this link.

Unrelated to the sale, some flowers to be enjoyed this time of year, native species occurring in gardens but not in the wilds of Princeton, is this Fothergilla I planted in the raingarden in front of the Whole Earth Center,



and, if I can get the chicken out of the way,

some celandine poppy. Unrelated to the lesser celandine that's radically spreading through gardens, parks and natural areas of Princeton, the celandine poppy is in the poppy family, makes small mounds that look good even when they aren't blooming. New ones pop up nearby, but not in a way that threatens to take over or spread unwanted into the neighbor's.

Saturday, April 14, 2018

Lesser Celandine Spreads Through the Neighborhood


It sure is pretty, but beware. It will take over your garden and your lawn. Too much of a good thing--it's the dominant story of our time, whether it be carbon dioxide in the air or a pretty wildflower spreading along the curb.

Lesser celandine (Ficaria verna), also called fig buttercup so as not to confuse it with the native celandine poppy, has essentially paved whole valleys. It's poisonous, and no wildlife have adapted to eat it, giving it a big competitive advantage. The most dramatic local examples are in Pettornello Gardens over at Community Park North, and downstream areas in Mountain Lakes. I've been watching it spread into the neighborhood one block from my house. Homeowners think it pretty at first, then feel distress at its aggressiveness.

Best to knock it out when it first arrives, with 2% glyphosate (wetland-safe formulation recommended when close to streams and wetlands). Digging it out is fraught with risks, as it spreads via small underground tubers, and probably via seeds as well.

Visiting my former home in Durham, NC, some years back, where it has only recently appeared, I found it growing in a couple adjacent yards, poised to spread via runoff into the local watershed. We asked the homeowners for permission to knock out the infestation. One neighbor agreed, while the other refused, indifferent to the impact her infestation would have when it inevitably spread beyond the boundaries of her yard. I had tracked another infestation elsewhere in Durham back to a homeowner's yard. He was grateful to find out what the plant was, and promptly eliminated it, as well as some he had given to his daughter in yet another watershed, thinking it was pretty.

These sorts of experiences put the lie to allegations that invasive plants are already so numerous that it's not worth trying to stop their spread. On the contrary, these plants' negative impact can be greatly reduced at the local level through timely action.

Thursday, April 11, 2013

Spring Sightings


Here is lesser celandine, which people tend to like at first, but then soon regret as it starts to take over the yard. A non-native spring ephemeral, the leaves will die back in a couple months. It's often mistaken for marsh marigold--a native that is larger and so rare I've never seen it growing naturally hereabouts. Though it's pretty, I recommend digging out the highly invasive lesser celandine as soon as it shows up in your yard, and before it sets seed. There's another (unrelated) wildflower called celandine, in the poppy family, that blooms later and is not invasive.


Another exotic, but not known to be invasive, is astroturf, here used by a neighbor as some sort of lawn bandage.

In the "look down to see what's up" category are the spent flowers of red maple scattered on sidewalks all across Princeton.

Here's the flower on a red maple donated to Potts Park a few years back in honor of a new-born son. The play equipment the tree is intended to eventually shade is in the background. Anyone who has felt how hot play equipment can get in the summer sun understands the need to get some trees strategically placed on playgrounds.

Friday, April 27, 2007

Pretty, but......



Lesser Celandine (Ranunculus ficaria),
is rapidly spreading into Mountain Lakes from its upstream stronghold at Pettoranello Gardens. Though attractive, its aggressive growth habit is ecologically destructive, as it quickly excludes other spring ephemerals.






The end result is a seamless carpet of this exotic species, offering none of the diversity needed to sustain wildlife. Lesser Celandine is sometimes confused with Marsh Marigold, a native that, like many natives, is rarely seen. In a month or two, the Lesser Celandine will disappear back into the ground, remaining dormant until the following spring.

Friday, May 04, 2018

A World Paved With Fig Buttercup?

There are many types and degrees of invasive behavior in plants. Dandelions are weedy in lawns but cannot survive in the shade of a forest. Japanese maple and Rose of Sharon may seed prolifically in a garden, but rarely show up in the nearby nature preserve. Bamboo, kudzu and Asian wisteria become like castles in the landscape--formidable, exclusionary, and deeply entrenched but limited in extent. They form dramatic, isolated clones that fortunately leave most of the forest untouched. Stiltgrass by contrast is a frail annual easily pulled, which nonetheless can have a far greater impact, coating the ground of large swaths of forest with billions of plants. It thrives in shade but tolerates sun, spreading into garden beds and lawns.

We, with our big brains and bodies, are built to take on large, distinct foes, yet quickly grow discouraged when faced with a threat that is small but hugely numerous, whether it be an overabundance of carbon dioxide in the atmosphere, plastic in the ocean, those tiny odorous house ants in the kitchen, or a ubiquitous weed in the garden. That pile of papers on the desk falls into this category as well. If the small, numerous thing is a disease pathogen that attacks us directly, we have strong institutions that engage to defend us. But if the small, transformative force represents an indirect threat, impacting our environment--our oceans, landscape or climate--rather than us directly, we lack both sufficient institutions and the will to resist. This can be considered society's achilles heel.

As a local example, our big-little hamlet of Princeton is being gradually paved over by a little plant that is pretty, and seemingly benign, yet is also extraordinarily aggressive, poisonous to wildlife, and overwhelming in its numbers and rate of spread. By mid-summer, it will have faded back into the ground, but in spring it looks like an expanding rash coating the land. It numbers in the billions, and cannot be easily pulled. Even its common name is hard to get a good hold on, with "fig buttercup" having displaced "lesser celandine" because the plant has the buttercup flower and fig-shaped tubers. The scientific name is Ficaria verna, with verna referring to its spring growing habit.

In the photo is an advanced invasion in Pettoranello Gardens that long ago spread downstream to Mountain Lakes Preserve. The more land it covers, the less edible the landscape is for wildlife. Our investment in open space acquisition is undermined as the acreage of functional wildlife habitat continues to shrink due to displacement of natives by introduced species that wildlife won't eat.



Now the fig buttercup is spilling into the nearby neighborhood along Mountain Avenue, spreading down-slope from one yard into the next. This patch spread through the fence, and through the neighbor's yard,

then popped out under the fence on the other side, ready to head further down the street. This species behaves like plastics pollution in that it becomes widely spread for lack of any organism able to eat it. Nature's checks and balances, developed through eons of co-evolution and adaptation, are circumvented when a new species like fig buttercup is introduced from another continent.

Here it is at Elm Court, a few blocks further on, poised to spread into and eventually coat their detention basin.

There used to be some solace in thinking that fig buttercup was limited to low, wet ground, but here it has become established along a slope next to the stage at Pettoranello Gardens. Audience members will slip on it, pick up some of the underground bulbs in the treads of their shoes, and transport the plant to new locales. What will stop it from eventually paving all of Princeton?

For contrast, here is the native marsh marigold, with which the fig buttercup is often confused. It's growing on the edge of the stream in Pettoranello Gardens because I planted it there a few years back. It's bigger and more showy, but doesn't take over like the fig buttercup. This is the classic example of how many landscapes have become dominated by invasive introduced species, while the native plants become rare.

Another attractive native yellow flower in spring is celandine poppy (unrelated to "lesser celandine"). I've never seen it growing naturally in the Princeton area, but it is used in landscaping. It has a nonnative lookalike that can be weedy but not as invasive as stiltgrass or fig buttercup.

Because fig buttercup is so aggressive and so hard to remove manually, careful use of herbicide is really the only means homeowners and preserve managers have to prevent it from getting established and ultimately taking over. Early detection and rapid response are the best recipe for minimizing herbicide use. We can't wait a million years for nature to adapt and re-establish balance, as one of the more bizarre books on invasive species has claimed.

Maybe research could eventually lead to a biological control being introduced to limit the fig buttercup's aggressive spread, but that requires that institutions be in place that can afford to do the many years of research and testing required, with no guarantee of success. In the meantime, fig buttercup continues to pave Princeton, one nature preserve and yard at a time.

Wednesday, January 25, 2023

Princeton's Nowhere Land Might Have a Future

The municipality of Princeton's newsletter broke the news last week that the town has been awarded a $552,000 Climate Solutions grant to restore 45 acres of forest at Community Park North. Kudos to the town, and to FOPOS, which will help with the project. Now, what sort of forest, you might ask, is so degraded that it requires more than $10,000/acre to restore? I stopped by last week to have a look.

It's appropriate that the sculpture that now graces the entrance to the woods at the back of the Unitarian church parking lot appears to be in mourning. 

Many hikers who head down the trail won't notice anything amiss, but for me, Community Park North woods has the feel of a post-apocalyptic landscape. Walking its trails, you can imagine yourself to be one of the fortunate or unfortunate survivors after civilization has extinguished itself, leaving invasive species to overrun the wreckage. 

For a virtual tour, click on "READ MORE," below.

Thursday, May 02, 2013

Lesser Celandine On the March


I thought my photo here of Lesser Celandine at Pettoranello Gardens demonstrated the plant's capacity to completely "pave" lowland areas.


But Pat Palmer sent me some even more demonstrative photos, taken April 16, showing its rapid spread through the lower portion of Institute Woods close to Rogers Refuge.

If one's looking for good news, one could point to the multi-stemmed shrubs, which are likely spicebush that have grown back since deer culling has reduced browsing pressure. Birders link increased nesting activity in Rogers Refuge in recent years to the resurgence of spicebush.

Saturday, June 04, 2016

Central Park in Spring


Central Park back in April, where a glorious nature is framed by a Manhattan skyline, like a verdant postage stamp in the Forever series, 50 blocks long and 3 long blocks wide.

The land's mix of rock outcroppings and swamps, a desire to emulate parks in European countries, and a healthy dose of 20/20 foresight (short history here) all played a role in sparing this ground from economic imperatives, a place where nature can have its day, every day.

Central Park is ringed by museums of art and history, but Central Park's history is of the living sort, etched in infinite varieties of green and blue, enduring but ever changing, bottomless in its imagination, needing no roof other than the sky.


Spring migratory birds, shuttling like ambassadors between earth and sky, continent and continent, drew a crowd of admirers welcoming their return, cheering their journey, as if the birds were sailers just off the ship.


The warblers gobbled down proteins and energizing fat in the form of insects nourished by a patron oak's foliage,


while a raccoon's interest in the tree was more structural. Indifferent to our earthbound attention, it snoozed through the day in its high rise apartment (no elevator but rent controlled) in the crotch of the tree.

I could count on one hand, well, maybe two, my visits to Central Park, and yet it strikes deep chords within. Buildings are usually framed by nature, but in Central Park, its the buildings that do the framing. Get to know plants on a first name basis, and they will become like old friends you run into wherever you go. Central Park is like seeing an old friend all dressed up in a suit for the first time.

The habitat restoration being done along the trails of the Ramble are not yet Shakespearian in depth--Shakespearian here defined as the more you look, the more you see. But the restoration of expanses of native wildflowers, grasses, sedges and ferns on the forest floor is sufficient to trigger memories of the rich understory many eastern forests had just a few decades ago. Though ringed by concrete and highrise buildings, Central Park has in some ways a better chance to be natural than more rural areas thrown out of ecological balance by intense browsing pressure and unfettered invasive species.


I know of only one bluebell growing in Princeton's preserved open spaces. Central Park has many, protected from their primary threat, straying pedestrians.


A cool-season grass, presumably native, is being used on slopes for erosion control.

One reason why prospects are good for native plant restoration in Central Park is the vast pool of potential volunteers to draw on, given the auspicious ratio of NY's residents per acre of greenspace.


Not that one needs any additional evidence of the shear scale of human numbers in NY, but the Run-As-One fundraiser that day in Central Park drew 8000 participants, royally served by a row of Royal Flushes extending as far as the eye could see, that might rival some nearby buildings if stacked one upon another. Might this be an irreverent artist's vision of infinity?


How does one capture the scale of the operation, all of which must be periodically latched to stretched out trailers and hauled away for a bit of refreshing? Clearly, I digress, but then again, how many nature posts are thoughtful enough to provide a bathroom break midway through?


Segueing smoothly back into nature, here, a Fothergilla ornamenting some snazzy bins.




Park volunteers were spending a beautiful spring afternoon immersed in their own sort of marathon, pulling weeds, including the lesser celandine, that pretty but very rapidly spreading plant that had a post devoted to it earlier this spring.

The leader explained that herbicide use is not allowed in the park, so they're having to pull each lesser celandine individually. They showed me the tuberous roots. Pretty slow going, but fortunately, there isn't much of it in the park.


A few places in the park benefit from a thoughtful lack of intervention. These spent daffodils are being left unmowed so the post-bloom leaves have a chance to feed their roots for the next year.


There was some conspicuous smooching between a tree and boulder, familiar to anyone hiking the Sourlands or the Princeton Ridge. Nature has always thrived on an intimate relationship between the animate and the inanimate.

A gentle breeze propelled sailboats and memories of daysailer days.

Princeton has a couple of these Carolina bells (Halesia), one on Snowden, one on South Harrison. Strangely, almost no dogwoods were to be found in Central Park.


A frame within a frame, as nature, framed by the city, frames a sculpted shelter.


A grove of elm trees brings back memories of what American streets used to look like before Dutch elm disease swept through.





Leaving the park, we found Teddy Roosevelt in good company at the entryway to the Natural History Museum. Might he offer them horses as well? Looks like they're all trying to get back to the nature in Central Park.

Just inside the Natural History Museum, there appeared to be an allegorical confrontation between Truth and Towering Ignorance. Might Congress's high dome be accommodating something similar? Nice to see that T-rexian Truth had a nice set of choppers, though it wasn't clear who was going to win.