As reported in TapIntoPrinceton, the Labyrinth Bookstore will be hosting a talk about mushrooms by naturalist, forager, and educator Maria Pinto, Thursday, Feb. 19, at 6pm.
Ms. Pinto's broad interests in cultural and ecological interconnections inform her approach to this fascinating subject. Our Friends of Herrontown Woods is co-sponsoring the event. More info about Ms. Pinto and a colorful description of her debut book is on the Labyrinth website.Princeton Nature Notes
News from the preserves, parks and backyards of Princeton, NJ. The website aims to acquaint Princetonians with our shared natural heritage and the benefits of restoring native diversity and beauty to the many preserved lands in and around Princeton.
Wednesday, February 18, 2026
Maria Pinto Speaks on Mushrooms at Labyrinth Bookstore, 2/19
Thursday, February 12, 2026
End of an Era for Skating on Carnegie Lake?
By chance, I was listening in on this week's Princeton town council meeting via Zoom when the subject of ice skating on Carnegie Lake came up. Turned out that town staff had quietly removed Carnegie Lake last year from the list of potential skating sites. Council member Mia Sacks expressed surprise that council hadn't had an opportunity to discuss the decision.
Staff explained the logic behind discontinuing what had been a long tradition of permitting skating on the lake when the ice reached sufficient thickness. Parking has become limited; staff testing of the ice involves some risk; and emergency services had concerns about the large size of the area between Washington Rd and Harrison Street where skating had traditionally been permitted. Fear of litigation, and fear that social media would draw large, unmanageable crowds, also drove the decision.
Though the concerns had some logic, there was some misinformation put forward in support. Staff knew of only one time after 1996 that skating had been allowed on the lake, but this blog documents five: 2007, 2009, January 2014, February, 2014, and 2015. (Update, 2/16: A sixth occurred in January, 2003.)
One council member claimed people had died from skating on the ice, but offered only the recollections of a relative as evidence. It's very easy to research this sort of thing. The Papers of Princeton website allows word searches of all papers published in Princeton going back to the 19th century. By typing "death" "carnegie lake" into the search box for Papers of Princeton, 78 results come up. Among the 78 I could find no incidents of death from skating on the lake. There was only one incident of death while ice skating, in 1943, when two boys had unfortunately strayed off of Carnegie Lake and skated upstream on the Millstone River. I found five instances of drowning in the lake or canal, unrelated to skating, between 1985 and 1996, and one obituary that told of the deceased's fondness for skating on the lake. If anyone finds documentation that contradicts the above, please contact me.
There was reference at the meeting to a skating injury on Carnegie Lake that had resulted in a lawsuit. The Town Topics reported that the lawsuit dated back to 1996. Skating has been permitted six times in the thirty years since, so it's not clear why the lawsuit would be taking on relevance now.
At the council meeting, four members of the public described how skating on the lake had been a magical experience for them as kids and adults--one of the things that had made living in Princeton special through the years. They pointed to the new parking garage not far from the lake, and asked if the empty Butler tract could be another parking option. One made the argument that during extraordinary cold spells like this, some people will skate on the lake regardless, so it would be safer to provide safe boundaries.
One unspoken cause of the policy change could potentially be the loss of institutional knowledge. The gap between 2015 and the deep cold of 2026 was long enough to weaken a tradition that, like all traditions, is sustained through repetition. Who on staff could remember all the trouble spots to check and mark off on the lake?
Skating has been permitted this winter at a small pond at Smoyer Park, but it's not the same.Though it's conceivable that policy will be reassessed, and at least a small part of Carnegie Lake will be opened to skating if and when we get another sufficiently cold spell in the future, what are the chances that the wonderful tradition will ever be fully revived? For those who weren't around to witness past permitted skatings on the lake, here's a taste of the magical experience that would be missed.
From Winter in Residence, 2007:
The arctic air blew in and Winter, quietly working in its favorite and most deceptively magical medium, transformed a pretty but otherwise cold and unwelcoming lake into a dancefloor, public square and sports arena. Working without a budget or publicity, nor any tools beyond serendipity and physics, Winter drew thousands of local residents to a spontaneous community festival down at Carnegie Lake.
Monday, February 02, 2026
Sweetgum: Embedded Mysteries of a Tree and Its Rare Paneling
A tree can be many things for many people: beautiful or a nuisance, its wood low-grade or its grain profound. A sweetgum tree is all these things for me. This post will give you a tour through sweetgum's beauties and annoyances, including its surprising use as high-end wood paneling in the 1920s and 30s.
First, regard the beauty. What other tree offers such a panoply of colors in the fall? Yellows, reds, purples, orange--sweetgum does it all. True, those powerful colors are only generated by trees that receive adequate sunlight, but there is some wonderful, creative chemistry going on there. Carotenes, xanthophylls, anthocyanins--these are the words that exercise the tongue while stirring curiosity about the possible purpose behind all that color.At least near water, one natural check on sweetgum's rampancy is beavers, who apparently love them for their inner bark laden with sweet gum--the liquid amber found in its latin name, Liquidambar styraciflua. This photo was taken during a walk at Plainsboro Preserve ten years ago. The beavers' preference was so strong, and the sweetgums so numerous, that we saw no other species of tree being chewed upon.
The story of American gum wood dates back many centuries. Nature requires many years of favorable growth to produce a masterpiece, and in the vast stretches of our southland forests, extending from the Atlantic to the Mississippi valley and beyond, the quiet work of building cell and fibre was going on long before DeSoto and his valiant men first beheld in wonder the mighty "Father of Waters." What a marvel of creation, when from soil, moisture, and sunshine this fine wood came into being, now to be transformed by the hand of man into products that contribute to his well being and enjoyment.
Lumbermen have long known gumwood, yet vast tracts have been left standing while other interspersed hardwoods of widely varying species which happened to be wanted at the time, have been cut out.
The tree itself, as it displays its lofty and graceful symmetry, is one of the glories of our native forests. Its sturdy proportions are enhanced by masses of scarlet, orange, and yellow leaves, which change, as the summer wanes. In size, it is heroic; one hundred feet to one hundred fifty feet in height, with a diameter of four or five feet, is not unusual. And some idea of the extent of growth of this important tree may be gained from the fact that with the exception of the oaks, gumwood exceeds all other hardwoods.
Now no wood has more wonderfully interesting patterns than figured gumwood, but it is one of Nature's riddles to account for them. The pattern is not produced in the usual manner by quarter-sawing, although this process will improve any figure if it is already there. All one can say is that some trees have pronounced figured wood, others varying degrees of pattern, and many which show but slight indications of it. Undoubtedly the condition of the soil and the location of the individual tree affect in some mysterious way the structure of the wood. Only when the tree is felled, does the grain show itself as plain or figured. That is what makes the gumwood tree so interesting; it is like finding a }ewel, the value of which depends upon hidden qualities brought out by cutting and polishing.
The figure ramifies through the wood at random, obeying no known laws. Gumwood logs will each display differing patterns, some subdued, some intricate and ornate.
Europe has long recognized the exquisite beauty and texture of American gumwood. In fact, England, France, Italy, Spain, and other countries were first to recognize its fine working qualities. In America, however, its light was for a time hid under a bushel, so far as public acquaintance with its true worth is concerned. But now, due to growing appreciation of its merit, the valuable products of the gumwood tree stand forth proudly as "American gumwood,'* nothing else -so named, and so prized. The old adage, "a prophet is not without honor, save in his own country," no longer applies, if we may adjust this metaphor to a tree.
Here's a career move that musicians know well--a wood that needed to cultivate an audience abroad before it could be valued at home.
Tuesday, January 20, 2026
The Many Things a Snow Can Do
Skiers must be happy with the snow that looks like it will stick around all week, but even if you don't take to skiing, a snowstorm like the one we just had presents all sorts of opportunities.
There's the chance for a no-salt collaboration with nature: scrape as much snow as possible off the driveway in the morning, then let the sun do the rest.Thursday, January 08, 2026
Training Deer to Eat MORE Japanese Knotweed
This post represents a first for PrincetonNatureNotes.org, in that it is written by someone other than me. Mark Nowotarski lives in Stamford, CT, and contacted me more than a year ago after discovering a 2014 post I had written entitled Training Deer to Eat Invasives. Independently, he had begun foraging the Japanese knotweed growing in his backyard (young shoots are edible) and noticed that deer began browsing it as well. Released from any co-evolved limits on its growth, Japanese knotweed has spread across the US and globally, displacing native species and overwhelming any human efforts to counter it. Unlike people, deer are 24/7 land managers. Their appetites decide what can and cannot grow in our yards and woodlands. Training deer to eat a relatively edible species like Japanese knotweed could conceivably, in some situations, relieve browsing pressure on the native plant species deer tend to prefer. As the deer in Mark's backyard continued to consume young sprouts of Japanese knotweed, he sent me photos and text that I incorporated into a post a year ago.
This past growing season, Mark expanded his experiments and observations, exploring how a willingness to browse Japanese knotweed could pass from one generation of deer to another. It's still unclear how much of an impact deer browsing could have on the spread of Japanese knotweed, but it's an interesting inquiry. Along the way, we learn about deer family dynamics, the potential grazability of another uber-invasive, porcelainberry, and even the possibility that deer saliva affects the chemistry of plants. Thanks to Mark for sharing his work with us.
Training Deer to Eat MORE Japanese Knotweed
By Mark NowotarskiIn our post last year, “Training Deer to Eat Invasive Plants – Japanese Knotweed”, I shared observations of white tailed deer (Odocoileus virginianus) browsing a patch of Japanese knotweed (Reynoutria japonica) in my backyard in Stamford CT. The local deer had learned to browse the knotweed continuously from spring to fall resulting in drastically stunted canes. This had allowed numerous native plants to recolonize what had previously been an invasive monoculture. Steve and I speculated that perhaps if we cut the fully mature canes in other nearby patches of knotweed (i.e., coppicing), new shoots would grow and the deer local to those patches might browse the new shoots as well. I’m happy to report that that strategy at least partially worked.
Deer Raising Fawns on Knotweed
Before we talk about manual coppicing, let’s talk about how it’s occurring naturally. This first video, shot in May in my backyard, shows you what deer browsing spring knotweed shoots looks like.
This particular buck may well be one of the fawns raised on knotweed in my backyard in the prior summer of 2024. Does and fawns form a family group when the fawns are born in late spring. They normally stay together and browse in the doe’s home range for a full year before dispersing shortly before the doe, if she’s pregnant, gives birth to the next year’s fawns. This is how last year’s fawns learn to eat the new shoots of knotweed that sprout in the early spring. The early spring browsing by last year’s fawns coppices the knotweed so that when it sends out new shoots at a convenient two foot height, the new shoots will be available for the new fawns born in late spring.
This year, our doe was, in fact, pregnant and sometime in June, she gave birth to triplets. Triplets are relatively rare (1 in 10 pregnancies) and indicate that the doe is well fed. By July, the doe and the new set of fawns were out browsing the knotweed previously coppiced by last year’s fawns before they dispersed.
In the foreground of Fig. 2 you can also see several native plants growing up through the coppiced knotweed. On the left is Canadian goldenrod (Solidago canadensis). On the right is Northern lady fern (Athyrium angustum) and sensitive fern (Onoclea sensibilis). The deer would occasionally take a nibble of the natives, but they concentrated primarily on the knotweed.
I had set up a motion activated trail-cam to monitor how often, and for how long, the doe and fawns browsed the knotweed over the summer. They returned 4-5 times a week and browsed 5-15 minutes for each visit. This lasted from when I set the camera up in July all the way through late October when the knotweed senesced (i.e., dropped leaves and turned brown). So far this winter, the doe and fawns are still stopping by several times a week. In late October an 8-point buck also stopped by in the middle of the night. After a bit of hide-and-seek with the doe in the knotweed, they mated. We can now hopefully look forward to new fawns this spring.
The cycle of fawns being raised on knotweed and then dispersing in the late spring to new territories may be an important mechanism for the spread of knotweed browsing by deer. The question then becomes, can we spread it even further by coppicing canes ourselves.
Expanding Knotweed Browse with Manual Coppicing
At the same time I was monitoring the deer in my backyard I also set out this past year to explore the knotweed stands in our local parks and land trust sites to see if I could find additional evidence of deer browse. About half of the stands I inspected showed signs of early spring browsing. About half of the spring-browsed sites also showed continued summer browsing. Several of the summer-browsed sites showed a significant expansion of the browsed area versus last year. This was evidenced by areas with tall old canes from last year but only shortened canes this year. The deer hadn’t eaten the knotweed last year and it grew to full height. This year, however, they started in the spring and continued through the summer and fall keeping it short.
To try out the manual coppicing experiment, I selected four sites where there was either no early spring browsing or where there was some spring browsing but no rebrowsing of the new shoots emerging from the coppiced canes. Two of the sites did not show any rebrowsing of the coppiced canes. These sites either had no spring browsing or very scattered spring browsing. The knotweed threw out new shoots which grew to full height despite clear evidence (e.g. footprints) of deer wandering by. Apparently, the deer near those stands had not been sufficiently acclimated to knotweed as a source of food.
In the other two sites, however, the deer did resume browsing the new shoots thrown out by the coppiced canes. These sites had heavy spring browsing and well-worn deer trails right next to the knotweed stands.
The next set of figures shows the history of my coppicing experiment at one of the sites where the deer resumed browsing.
Unlike my backyard, however, these new shoots were not rebrowsed. By July they had grown to full height. This, along with the well worn deer trail right next to the knotweed stand, made it an ideal location for the coppicing experiment.
The next photo (Fig. 4) shows a section of the knotweed stand where I cut a 6 foot wide by 12 foot long section of the full grown knotweed canes to about 2 feet off of the ground.
I cut the canes at a bias so that when I inspected them later on, I could tell whether a cut cane was my doing (angle cut) or a deer browse (horizontal cut). Cuttings were placed where they could not resprout or be washed downstream.
A few weeks later I went back to inspect and, much to my delight, the deer were browsing the new shoots emerging from the manually coppiced canes (Fig. 5).
Where I had cut the canes, the ends were frayed and the canes turned black down to the next joint. Where the deer browsed the canes, however, the ends appeared to be sealed off and even flared out as if from accumulated water pressure coming up through the knotweed. The canes below the deer browse remained green. It makes me wonder if there is something in the deer saliva that causes a deer browse wound to heal quickly. Perhaps knotweed has evolved this way from browsing by sika deer (Cervus nippon) in their home range in Japan.
Once I confirmed rebrowsing of the new knotweed shoots at this particular site, I set up another trail cam to see what sort of deer were coming by. I half expected another family of a doe teaching fawns to eat knotweed.
This buck and several others came by 4-5 times a week to browse not only the knotweed, but the invasive porcelain berry (Ampelopsis glandulosa) growing over the area in the foreground and hanging off of the uncoppiced knotweed canes in the background. In fact, I suspect that the porcelain berry is the primary reason the deer were there. The knotweed was just an additional food source.
Deer in a given area learning to eat Japanese knotweed appears to be a multi-year process. It starts with initial occasional browsing of early spring shoots. The spring shoots are then browsed more intensely in the ensuing years. Eventually the deer start browsing the new shoots growing from the spring browsed canes. If the knotweed is in a doe’s home range, then she starts to raise her young on knotweed and then the process spreads as the fawns raised on knotweed go on to establish their own home ranges.
If you try your own coppicing experiments, please let us know how they work out. I’ve joined a project on iNaturalist called “North American Knotweed Ecology Project” where we can share our observations. iNaturalist is a great tool for finding knotweed stands in your area. If you look carefully in the knotweed photos, particularly those taken in April and May, you can often see a deer-browsed shoot here and there. Sites with browsed shoots would be a likely candidates for coppicing experiments.
In the future I hope to learn more about the general phenomenon of deer adjusting their diets to consume invasive plants; how this affects browsing pressure on native plants; and what impact it might have on the deer themselves. The deer won’t solve all of the problems with invasives, but they may very well be an important part of the solutions.
Sunday, December 28, 2025
Year-End Update on Herrontown Woods - 2025
If you appreciate this blog, one way to give back is to support the work of the Friends of Herrontown Woods (FOHW), the nonprofit that we founded in 2013 to make the preserve usable again after long neglect. Our group now manages trails and habitat on 230 acres of municipally owned land in Princeton, and rely on donor support to pay our expenses. It's been a great year, and I'd like to share some of our accomplishments. Each donation provides support and inspiration for our work to restore habitat and history at Princeton's first nature preserve.
GOOD NEWS FOR PRINCETON'S SALAMANDERS
Herrontown Woods' large size, clean water, and wet terrain make it a haven for amphibians. The Princeton Salamander Crossing Brigade, founded by FOHW board member Inge Regan, is in its third year of helping hundreds of salamanders and frogs safely cross the road during their spring migration. 30 participants include experts and beginners, Princeton High School students and faculty, professors and community volunteers. A lively dialogue via whatsapp continues yearround. 2026 will mark a breakthrough, as Princeton municipality has agreed to close the road during the rainy nights in early spring when the amphibians are on the move. The initiative was written up in the Town Topics, TapIntoPrinceton, and the Daily Princetonian.
THE BOTANICAL ART GARDEN ("BARDEN")
Visitors to Herrontown Woods often describe it as "magical" and "unique." The award-winning Barden contributes a lot to that impression, having evolved since 2017 through a merging of many talents and visions. We keep adding native plants--some 160 species thus far--and have done surprisingly well at catching the weeds before they can spread. Kids love the charismatic wood frogs in the spring and the green frogs that take up residence in the summer. On the first Sunday morning of each month, we host a May's Cafe next to the gazebo, with coffee, tea, and baked treats.
SURPRISING SUCCESS WITH INVASIVE SPECIES
People are used to bad news about invasive species, but by being proactive we have largely vanquished many kinds of invasive plants that plague other preserves. In particular, through early detection and rapid response, we continue to protect Herrontown Woods and Autumn Hill Reservation from the uber-invasive lesser celandine. We also saved many trees by slaying a giant "wisteria monster" around Veblen House, and more recently have subdued another, nearly 3 acres in size, over near the main parking lot. Timely intervention is also protecting the preserves from Japanese angelica tree, bush honeysuckle, jetbead, porcelainberry, garlic mustard, mugwort, Chinese bushclover, and a new invasive shrub/tree so little known that it lacks a clear name. Late summer intervention is helping limit the spread of stiltgrass. All of this has been achieved through steady, incremental effort year after year by our volunteers and paid interns.
A COMBACK STORY FOR NATIVE SHRUBS
Native shrubs have a hard time of it in Princeton preserves. The combination of deep shade, deer browsing, and competition from invasive species has caused many types of native shrubs to literally lay low. The town's deer management program has helped, but pinxter azaleas, Hearts a' Bustin', and shadbush in Herrontown Woods still persist only in miniature, unable to flower. By transplanting some of these to sunnier spots in the Botanical Art Garden and caging them to protect them from deer, we are showing the public a beauty and vitality that had previously been suppressed. We're giving other native shrubs the sunlight and protection they need as well: alternate-leaved dogwood, silky dogwood, elderberry, buttonbush, and swamp rose.
A FLOURISHING WET MEADOW
Another successful FOHW project is managing the wet meadow at nearby Smoyer Park. Fed by runoff from the parking lot, it's actually a lowly detention basin converted by Partners for Fish and Wildlife long ago to native meadow through our initiative. Girl scouts had fun adding wildflower seed collected locally. A meadow is vulnerable to takeover by invasive plants like mugwort, Chinese bushclover, Canada thistle, and crown vetch, but strategically timed work each year to discourage those species has paid off. Each year the work has gotten easier as the weeds become fewer and fewer. Natives flourish if given a chance.
NATURE WALKS
In addition to periodic nature walks by Steve Hiltner, Sarah Roberts, and others, FOHW offered forest bathing walks this year, led by Rich Collins of the Friendly Territory. Steve continued to lead walks through the Princeton Adult School on Herrontown history, ecology, and geology.
Friday, December 19, 2025
Playing the Healer of Nature
One of PrincetonNatureNotes' sister blogs is FOHWard.org, specific to our work and play at Herrontown Woods, the fabled preserve that our nonprofit Friends of Herrontown Woods takes care of. Posts range from the celebratory to the comic, as in when we intervened to scuttle an attempted "theft" of a portapotty.
For those who imagine cutting invasive species to be dull work, a recent post on that blog, Stewardship and Discovery at Herrontown Woods, might be of particular interest. It captures how elements of beauty, effort, strategy, serendipity, and discovery can come together to make a stewardship session a rich and satisfying experience.
Cutting nonnative invasive shrubs, we are essentially deer with loppers. Deer move through the forest looking for something edible to browse. They generally leave the nonnative shrubs uneaten, and so to prevent those nonnative, inedible shrubs from taking over, we move through the forest with our loppers with an eye for "browsing" the nonnatives, to balance out the deer's persistently lopsided appetites. Unlike deer, we aren't in the woods 24/7, and so to have a lasting effect it's necessary to treat the cut stem so it won't grow back. By releasing native plants from competitive pressure, over time we make the forest more edible for deer and other wildlife, essentially expanding the acreage of functional habitat in Princeton.
Some would say that humans are an invasive species, so who are we to presume we can make a positive difference. But if we can be considered invasive, we are also equipped to play the role of stewards, to see the consequences of our invasiveness and act to heal the altered earth. As we move deer-like through the forest, our appetite is not an extractive search for food but for restoring balance. To abdicate on that role would be to deny what it means to be human.
I don't know if deer can appreciate beauty or serendipity as they browse, but we can. In Herrontown Woods in autumn, each leaf reveals its inner color. Each boulder is a work of nature's art, mottled with varied shapes of lichen and moss, like the mottled skin of whales navigating the oceans. To steward a preserve is, of course, a considerable task and responsibility, but in another way, working with nature is a great privilege, allowing us to realize our highest role, as stewards, appreciators, and healers of nature's creations.
Friday, December 05, 2025
Encounters With Old-Growth Forest
Ever since attending the induction of Rutgers' Meckler Woods into the Old-Growth Forest Network, I've wondered whether any woodlands closer by could be rightfully considered old-growth. Rare is the woods that was never logged. The forests we typically encounter are of more recent vintage, having mostly grown up from abandoned farm fields. There's a valley at Herrontown Woods with giant tulip trees whose massive roots have lifted the ground around them, as if perched on a pedestal of their own making. Might these and the nearby big oaks and hickories meet the standard? And what exactly is the standard for deciding? Below is an account of encounters with old-growth, old stuff, and different forms of timelessness during recent travels.
When we headed north from Princeton to attend the wedding of a young couple in upstate NY, we had no idea that the theme of the trip would turn out to be old stuff and old growth. On the way up, we stayed overnight with friends whose house is filled with old furniture--a grandfather clock, of course, but also what may as well be called grandfather chairs that had been inherited or adopted from the curb, valued for their uniqueness and style regardless of how practical they might be. Each chair around the dining room table, each lamp, vase, and bureau, had a story behind it. A crank telephone perched on the wall in the kitchen, ready to call up the whisperings of distant ancestors. I found great comfort in this approach to stocking a house, even if a chair's quirky ergonomics didn't conform to modern expectations.
The next morning, we walked through Borden's Pond, a second growth woods whose scattered "wolf" trees and sedge meadows also have a story to tell. When the area was logged long ago to make pasture, farmers left a few scattered trees as shade for the livestock. Those trees, lacking any competition, with sun all around, grew thick lateral branches, so different in shape from the straight, younger trees--the "second growth"-- that grew up after the pasture was abandoned. This can't be called old-growth, I suppose, but it certainly has individual trees that go way way back.On this particular shortleaf pine, the bark changed dramatically about 20 feet up, from shaggy to smoother, platy bark extending to the top. That would suggest the tree is well over 150 years old."The bark changes on most species when the trees are over 150 years old, looking very different from the bark of younger trees.
Excellent signs include balding bark, shaggy bark (separating or curling strips), craggy bark (deeply grooved, fissured bark), and platy bark."


















