Thursday, March 25, 2021

Some Unusual Trees

 Here are some encounters with unusual trees in Princeton. 

In the Institute Woods, we saw a couple beech trees some distance from a trail and took a closer look. Not quite the California redwood that people could once drive a car through, but similar in concept. 

Another beech nearby was harder to pose with.
The view up the inside of the trunk.

Bark with this shaved appearance, seen recently in a deep forest in northeastern Princeton, is called "ash blonding," said to happen when woodpeckers go after the emerald ash borers inside the ash tree. Note the tell-tale "D"-shaped holes where the borers exit. 



More uplifting was this tall spruce, which during the holidays sports a shining star, which then gets replaced on the owner's March 17 birthday 
by an Irish clover. 

Here's an odd sighting. It looks like an ordinary stump, but the tree was clearly cut down and removed. The forest is quite old, so the logging must have been long ago. My guess is that it's the stump of a chestnut tree harvested a century ago. One of the many wonderful traits of the native chestnut, lost to an introduced disease a century ago, was its resistance to decay. Working briefly for a forester in Massachusetts in the 1970s, I saw whole logs of fallen chestnuts still intact despite the passage of many decades. I'm ready to be wrong on this ID, but that's what I'm going with for now.

A month ago, I stopped by the TRI property to check up on a couple native butternuts planted there by Bill Sachs. The two trees are flourishing except for some vines that I really need to get back there and cut. They were planted close to where Bill and I harvested about fifty nuts, perhaps the last native butternut harvest in town before the bounteous tree was blown down in a storm. Thanks to Bill, the harvest turned into many saplings that we've planted in many locations in town, including Harrison Street Park, Herrontown Woods, Mountain Lakes, Stone Hill Church, and TRI. The tree has a gangly growth form, but the nuts are said to be delicious. The tree needs our help because of an introduced disease that has laid it low. This one's look really healthy thus far.

Some other stories about unusual trees:


Sunday, March 21, 2021

Amphibians Risk Their Lives Crossing Herrontown Road

This past Thursday, March 18, I received a phone call from Fairfax Hutter with news that the amphibians would be migrating that night. A long spell of dry weather had held the frogs and salamanders back. Now, with rain and temperatures in the 40s, they would be moving in large numbers towards vernal pools to breed. Fairfax was headed out to the Howell History Farm area to protect amphibians crossing the road, but she was hoping I could grab a reflective vest and flashlight and walk along Herrontown Road. Directing traffic would have required coordination with the police, and lacking the necessary equipment, I didn't get out there until Saturday morning, to see if what sort of traffic control could be warranted in the future. 

The photos I took were reminiscent of the snapshots in Chris Jordon's documentary "Albatross," of birds killed by an accumulation of plastic in their guts. 
No driver means to kill a spotted salamander, and no one wishes plastic waste to ultimately kill an albatross. So much of the damage we do is inadvertent, free of ill intent. Climate change and plastics pollution are a giant, collective "Oops!" 



The number of roadkilled amphibians between the Autumn Hill Reservation parking lot and Stone Hill Church came to ten. The death toll would rise with additional cars passing by. One fascinating aspect of population is that, as the number of people increases, the behavior of each individual becomes more important even as the individual feels less and less responsible for the collective impact.

Predictions of future carnage need to factor in the increased traffic generated by a recovering economy. If the 90 acre Landwin tract on Herrontown Road were to be developed, the combination of lost habitat and more traffic would not bode well for the spotted salamanders, which Fairfax says are about to be listed as an NJ species of state concern. 

Meamwhile, the frog-filled vernal pools near the Herrontown Woods parking lot were drawing a lot of attention from kids passing by on the trail. Fairfax said she had documented a record night along the stretch of road where she had played the role of crossing guard, with 98 crossings

In Princeton, as far as I know, there has been no effort to protect amphibians crossing roads in the spring. Here, at least, is some evidence to spur better preparedness for migrations to come.

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.

Monday, March 01, 2021

Nature as a Partner, Even in Winter

Working With Nature

In winter, with the plant world frozen and the ground cloaked with snow, it's easy for a gardener to feel cut off from the nature that has meant so much to us through this pandemic. It's possible, though, to work with nature even during this season of suspended animation. The elemental aspects of nature are always ready to be tapped. Welcome sunlight through windows to help brighten and warm the house. Hang washed laundry on racks to let the air effortlessly absorb the moisture. Moisten plates in the sink to soften the dirt before washing. To do these things is to participate in a partnership with nature. Snow can be seen as a natural way of recycling light. It brightens the world rather than letting the light be swallowed by the drab browns and grays of the winter landscape.

Nature as Energy Detective

In a way, nature speaks, even in winter, and can offer useful clues to those who listen and observe. The location of spider webs can sometimes indicate where warm air is escaping from the house in winter.  The patterns that snow makes on roofs as it melts tell a lot about what's going on inside. Above the garage of this building is a living space on the left, and a stairwell on the right. Because the living space is insulated, the snow is slower to melt.


The two little spots where snow is melting on the roof of my house suggest heat is escaping there. One of those spots is where the heat duct extends almost to the ceiling in the bathroom, creating a hot spot that could use more insulation above it. 

The ribs on this roof reveal where the evenly spaced wooden rafters insulate the shingles from the warmed attic air.

Massive icicles hanging from the roof of my childhood home were a delight, but looking back with an adult's eyes, their splendor was probably due to heat rising from a poorly insulated house to send melted roof snow towards the gutters. 

Winter Joys

While adults often view snow and ice as an impediment and chore, it's often the kids who serve as conduit for reminding the adult world that snow and ice are really nature's invitation to a good time. 

Skating on Carnegie Lake

It was kids, and the kid in me, that led to these past accounts of skating on Carnegie lake:

2015: "IceLax" -- playing lacrosse on Lake Carnegie

2014: "When Carnegie Ice Melts Memories" -- How Carnegie Lake provided a window into my own childhood.

2010: Patterns in Carnegie Lake Ice -- improbable beauty in the ice, in photos taken from the Harrison Street bridge

2009: Patterns in Carnegie Lake Ice -- more remarkable patterns found while skating

2007: Winter in Residence -- when people flocked to Carnegie Lake in Februrary, 2007




Saturday, February 20, 2021

Gratitude as a Salve for Grief

The snow rests so softly on the land. I want to relax, and rest content like snow perched on a stone.

I want to enter into this photo and give in gladly to gravity's nestling pull. But I live in two worlds right now, 444 miles apart. In one world, there was an Oswald and Elizabeth Veblen, who loved land and bought 100 acres of it, then gave it all away, to us, to enjoy in perpetuity as Herrontown Woods. 

In the other world, up Shoccoree Drive in Durham, NC, there is another 100 acres, similarly perched high in the headwaters of my beloved Ellerbe Creek, with similar riches of plant life rooted in geologic drama, where the Carolina slate belt drops down into the Triassic Basin. That land, which helped inspire my founding of a watershed association in pre-Princeton days, has like Herrontown Woods always felt timeless to me, unique in its splendor, resistant to the bulldozer as heartwood is resistant to rot. 

But without the vision and generosity of a Veblen, nor the collective generosity of an open space tax to pay the owner's price, even timeless land can one day find its time is up. Hills and valleys resonant with beauty and history erased beneath a cookie cutter development. It hasn't happened yet. There's still a scintilla of hope, as neighbors organize in opposition. Might I have done more to save that land, 444 miles away, somehow found a wealthy donor to spare it? Can something still be done? That is the background anguish that now intrudes on the pleasure of a walk through snowbound Herrontown. 

Surprisingly, I feel a bit sad for the landowners in Durham who are selling to a developer. It took sixty years, but the Veblens' donation back in 1957 has contributed to a rediscovery of the much larger legacy they left behind, at Princeton University and the Institute for Advanced Study, in human rights, national defense, and early computer development. Their donation of a beloved nature preserve, house, and cottage is helping keep their story alive. Who could put a price on enduring gratitude--a kind of immortality--or the joys and peace this land of rock, water, and wood brings to so many?

So, let the snow settle,


and the pin oaks cling to their leaves,
and the seeds of wild senna sleep peacefully through winter.
Let the wooden man contemplate his whitening hair,
and a house grow eyebrows in the snow.
Let quiet beauty reign here, no matter what the distant news may bring. 


Let gratitude be a salve for grief.


Thursday, February 18, 2021

Recreational Trails and Resilience

The Friends of Herrontown Woods and other stewards of natural lands in Princeton have been asked to give input to the state bike/ped office and the Federal Highway Administration about trail resilience in these times of rapid change. I decided to put my feedback into a blog post. We steward trails at Herrontown Woods and Autumn Hill Reservation in Princeton, NJ--about 220 acres total. Fit into the categories we were asked to address, here is some of what we've learned over time:

Trail vulnerability and resilience to natural hazards

Climate change is impacting our trails in multiple ways. Trees still pull water out of the soil during the growing season, making most trails reasonably dry during the summer and fall. In the past, winters were cold enough to freeze the ground in the winter. Now, with warmer winters, trails can get wet from rains in the fall and remain wet and muddy until the trees awaken again in late spring. 

Trails are becoming more vulnerable to erosion, give the more intense, longer, and more frequent rains, and the reduction in freezing in winter. Trails on a slope can become like streams as they catch runoff from the surrounding ground and convey it downhill. This makes water bars, which serve to divert runoff from trails, all the more important to build and maintain. 

As ash trees killed by the introduced Emerald ash borer become brittle over time, they will fit in the category of natural hazards. We've been fortunate to be able to take some down in the vicinity of our botanical garden, but it would be impossible to cut down all of them in the forest. They can serve as useful snags for wildlife, at least.

Designing trails for climate change and future conditions

We ground-truth potential new trail routes during the wettest times of the year. This has become all the more important as weather becomes more extreme. It's the only way we can know whether a particular route will be usable year-round. A route that looks dry during the summer may be impassable in the spring, when vegetation has yet to pull moisture out of the soil. This is the problem with having trail consultants spend a couple days in a preserve, and then make recommendations about trail routes. Ongoing observation is really helpful.

In some of our soils, it is the roots that maintain the firmness of the soil. We've been deceived at times by a seemingly dry route that, when it becomes a trail with lots of foot traffic, becomes muddy due to the breakdown of the underlying root structure that had been holding the soil together. 

No trail can be perfectly designed. We fortunately have a source of local "native" stepping stones that we can lay down on particularly muddy patches, and we use some boardwalking. Over time, we hope this will keep trails passable even as rain increases. 

Trails providing ecosystem services

Trails provide access to areas to cut invasive species or do other stewardship work. If invasive species are controlled along trails, the trails become essentially a corridor of restored habitat. Interestingly, trails can sometimes provide the necessary combination of disturbance and additional light necessary for some wildflower to grow that would otherwise get smothered by leaves or shade in off-trail areas.  

On the downside, trails can intrude on habitat, and also provide a route by which invasive plants like stiltgrass can penetrate into otherwise uninvaded areas of the preserve. 

Use of trails during emergencies (evacuation routes, emergency vehicle access, fire suppression, etc.)

We invited the the local rescue squad to do a practice rescue in our preserve. It was very helpful in acquainting them with the lay of the land. We also showed them areas where accidents could potentially happen, and are working on a better map of the preserve showing access points. 

Trails can serve as potential fire breaks, whether for fire suppression or for prescribed burns. We have yet to use fire as an ecological tool in the preserve, but fire often has a positive and historically important role in open spaces if prescribed and carried out appropriately.

Use of recreational trails during public health emergencies

We've seen a dramatic increase in trail use this past year, as well as an increase in volunteers to help at our preserve. Though hikers tend to be conscientious about wearing masks, some will want to avoid encounters along narrow trails. That gets us looking at how we could provide at least one trail that is wider than others. 

Nature has served as an indispensable balm, refuge, and recreational outlet for people during the pandemic. The pandemic has made nature preserves ideal for those who love not only plants and wildlife, but socializing safely with people as well. 

Tuesday, February 02, 2021

A Rather Long Snow Storm

Here in Princeton, we have artisanal snow removal services, as in this thoughtfully crafted mohawk for the Prius.
Good news about the frontyard raingarden: it works great as a snow garden as well.



During this extended, ground-breaking, or at least ground-exposing, Snow Removal Initiative (SNI), it was important to take frequent breaks to document the innovative "shoveling" technique being used. The Royal We Committee believes this approach, if successful, could serve as a model for other homeowners to emulate. Later in the morning, we saw neighbors beginning to utilize this very method, suggesting our demonstration project could have a transformative impact on snow removal in Princeton and beyond. 


The Initiative included a research component. Careful study of this cross-section of the cliff face reveals the various strata laid down by the storm. This having been an unusually long snowstorm, it's understandable that the darker patch in the middle was at first mistakenly dated back to the early Devonian. Further analysis and some equipment tweaking showed that snow in the darker stratum likely fell during the warmer daylight hours the day before, with the lighter layers above and below having been deposited during the preceding and following nights.

Other keen observations: some of the neighbors didn't get the memo. Recycling postponed until Saturday, or the mid-Anthropocene, depending on how long the storm lasts.

What is snow good for? Enforced social distancing, for one. Not likely to have a close encounter with the neighbor for some time to come. And the kids can sort of remember what it used to feel like to get a snow day.

Other writings on excessive snow include an oldie but goodie: Snowbound Language


Monday, February 01, 2021

Sourlands as Big Bro to Herrontown Woods

When my daughters suggested a walk in the sourlands, I took it as an opportunity to test out a theory: that Herrontown Woods is in some ways a miniature version of the sourlands preserve. 

The trails are certainly larger, wider, longer than those at Herrontown Woods, with sections of broad boardwalk between stretches of familiar mud.



Some things are of similar scale. Familiar at Herrontown and the Sourlands are efforts to aid hikers through muddy patches with dense gatherings of stepping stones,
and places where the rocky landscape threatens to swallow the trail whole with its boulders.
Whereas Herrontown Woods has its boulder field, beneath and through which a gentle stream flows, making a kind of stereo music in the spring, the Sourlands has Roaring Rocks, named for the spring rush of water beneath super-sized boulders. 

My daughter provided scale for the jumble of giants spilling down the valley. 
This long, smooth boulder, like a whale surfacing for air,  is an outsized version of a similarly shaped boulder that surfaces near the Veblen Cottage in Herrontown Woods. 
This rock face, too, is a larger version of a prominent geologic feature at Herrontown Woods, 
with a higher, longer view from above.

There's a familar play of lichens and mosses on the boulders,
and a familiar mix of smooth and finely fissured rocks.

These boulders, by the way, are not a legacy of glaciers, which did not extend this far down, but of igneous upwellings exposed by subsequent erosion of the surrounding, less resistant material.
Probably not a source of pride, but the Sourlands even has its own derelict fence, newer and longer than the one at Herrontown Woods. Something there is in a woods that doesn't love a fence.

The Sourlands probably has more examples of trees perched on boulders, if anyone were to count.
It took awhile to figure out the Sourlands' system of trail markers.
A half hour in, my younger daughter had a useful insight, that these two angled squares mean that the trail is about to turn left. 
Where the blue trail splits in two, one of the routes carries a black dot in the middle. Pretty clever.
The gas pipeline right of way at the Sourlands is steeper, with a more dramatic view than the one at Herrontown Woods. My daughters pointed into the distance, where the Manhattan skyline was clearly visible. That was a surprise. 
As at Herrontown Woods, the Sourlands pipeline is a mixed bag of invasive mugwort,
and chinese bushclover, with some native species like Indian grass and tickseed sunflower mixed in. Whenever I walk one of these right of ways, I think of Leslie Sauer's The Once and Future Forest: A Guide to Forest Restoration Strategies. Therein, read long ago, she made the point that these linear openings have a different ecological impact from the small, isolated, more circular forest openings that would naturally be created by fallen trees or fire. The linear corridor facilitates the spread of invasive plants and the parasitic cowbird in ways that natural, disconnected openings do not. 

One of the invasive plants spreading along the edge of the pipeline corridor is Ailanthus, or Tree of Heaven. The Ailanthus has in turn been expediting the spread of the newly arrived invasive insect, the spotted lanternfly. Cutting and treating Ailanthus--a favorite host of the lanternfly--is a way of discouraging both of these introduced species.
Sometimes smaller is better, as in Herrontown Woods' smaller problem with Ailanthus, and its smaller population of deer (thanks to the more intense management Princeton has been able to sustain), which reduces browsing pressure on native species. 

One of my favorite features at the Sourlands are these very shallow stream crossings, where there's no distinct stream channel. The water becomes like us, just one more traveler over stones, and we become like the water. 

The Sourland Mountain Preserve is ten miles from Princeton. Drive up 206 and take a left on Belle Mead Blawenburg Road.