Saturday, May 28, 2011


 The killing of two beavers at Pettoranello Pond two weeks ago brought into the spotlight two sharply contrasting views of the animals. Beavers are adorable, and impressive in their craftsmanship. One of my most serene memories is watching a beaver swim peacefully across a moonlit pond. Their approach to living--find an auspicious spot, transform it to your needs, and make a living there--has parallels with ours, and so can serve as a bridge of kinship between people and nature.
Their inclination to change their surroundings, as in the sticks and mud they were using to obstruct water flow under this bridge, also triggers a distinctly negative view of beavers as nuisance animals. People get a pond just the way they want it, plant some pretty trees, and then a beaver comes along, changes the water level and starts eating the trees. That's what was happening at Pettoranello Pond. Of course, if beavers are stigmatized for changing the environment, imagine what an animal community that could form and hold opinions would be thinking about us.

Beavers have been living in the canal and Lake Carnegie for a long time, and I had been wondering why they hadn't made it up Mountain Brook to Mountain Lakes and Pettoranello Gardens. Now that they have, I'd expect more will come. My hope would be that some way could be found to accommodate the beavers while keeping the pond level stable and any valuable trees protected. There are devices that allow water through dams without the beavers being aware. In my opinion, the beavers would do Pettoranello Gardens at least one favor by thinning out its thick stands of alder along the water's edge. If the beaver's additions to the dam obstructed storm flow, then a spillway for heavy runoff could be dug somewhere along the bank. The pond already has a bypass upstream of it for storm surges.

Monday, May 23, 2011

A Visit To Mercer Educational Gardens

I finally got out to the Mercer Educational Gardens for their annual plant sale. It's out past Terhune Orchards a ways, and features well-tended gardens and various useful demonstrations.
For instance, a variety of rainbarrels are on display. The giant white cistern, which looks like it holds a thousand gallons, is what you'd actually need several of if you were serious about capturing all the runoff from your roof.
I've been starting to see these lately--plastic rainbarrels made to look like pottery. These two are in tandem. The second one has an overflow pipe if they both fill up.
This appears to be a compost bin that actually converts the decompositional energy inside into classical decompositions which, if played backwards through the speaker on top, sound like music. Devotees of this obscure genre may be familiar with some of the more accomplished and experienced decomposers like Nevohteeb and Levar.

This sign explains how 41% of our "household trash" is compostable.

Maybe if more homeowners in Princeton read this sign,

(warning: pet peeve about to be taken for a walk)
they wouldn't keep dumping their high-nitrogen grass clippings on the street, where they create a mess and pollute the local waterways.

Thanks to the Mercer County Extension for encouraging people to do right by their gardens and their local streams, and showing them the way..

Sunday, May 22, 2011

Stalking the Rare Horsteria Westnut

What kind of tree could this be, so bright and fragrant a week or two ago,
with two kinds of flowers--some white, some lavender? Closer inspection showed it to be a horsteria westnut, that is, a horse chestnut being engulfed by wisteria vines.

If one's going to kill a tree--the likely outcome--this is one of the prettier ways to do it.

Lesser Celandine

Among invasive species, the most intimidating are not the giants like kudzu but instead the diminutive species that quietly multiply into millions, defying anyone to pull them all up. Lesser celandine, which has engulfed large areas at Pettoranello Gardens, cannot even be successfully pulled up, as each plant forms many bulblets underground that remain even if the plant itself is pulled. The species, which turns yellow this time of year as it goes into dormancy until next spring, continues to spread downstream into Mountain Lakes and beyond.

I've heard many testimonials from gardeners who love its yellow flower when it first shows up, then become distressed as it begins to take over the garden. Spraying with a low toxicity herbicide like 2% glyphosate (the active ingredient in Roundup) is the only way to get rid of it over time, unless one can cover it all up with a layer cake of cardboard and mulch when it first appears in the spring, robbing it of energy. Leave one plant, however, and the problem begins anew.

My Parents' Garden

One thing I did on May 8, the first Mothers' Day since my mother passed at the age of 94 earlier this year, is to pull garlic mustard at Mountain Lakes Preserve. The logic of this is rooted in my parents' backyard, in the '70s in Ann Arbor. They had just bought an old Tudor house, previously owned by a mathematician. That first spring, yellow primrose popped up along the garden paths, with swaths of pulmonaria, mayapples, solomons seal, bloodroot and trillium grading into a small woods. There was little difference between the cultivated and wild areas, the gardens being little more than a steering of nature's already fortuitous and ornamental energies, with a few gentle introductions like primrose and pulmonaria thrown in.

That order, which seemed timeless at first, began to slowly unravel year to year. A patriarch elm, its graceful arms spreading in a protective arc over the center of the garden, succumbed to Dutch Elm Disease. Myrtle, wisteria and bishop's weed (snow on the mountain) began their relentless expansions. Hours were spent in hand-to-root combat, as rock walls and less aggressive species came under ongoing threat of being engulfed by a monotonous, weedy tide. Garlic mustard slipped into the mix somehow, at first seeming ornamental enough to leave, then turning into brown skeletons later in the summer, flinging its seeds about before I thought to react.

The fight to save a valued balance was not against exotics, but instead against the aggressive plants, the preponderance of which happened to be exotic species introduced into the garden by chance or with the best of intentions. The wildflowers continued to bloom along the path edges, and one year a pawpaw sprouted mysteriously in one of the beds, eventually bearing tropical-tasting fruit. But the beauty and serendipity that make a garden a joy were under constant threat from a subset of plants with imperialistic tendencies.

That garden taught me more than could have been guessed about the forces that tilt the world towards imbalance, and the work required to counter them.

Wednesday, May 18, 2011

FOPOS Annual Meeting and Walk

Friends of Princeton Open Space had its annual meeting May 1 at Mountain Lakes House. Here, president Wendy Mager is pointing out the window to where the newly restored upper dam is now operational. The upper lake, which had become filled with eight feet of sediment over the past 100 years, has regained its original depth.
Water flows in a glistening curtain over the full length of the new spillway.

Guest speaker Bob Martin, who is Commissioner of the New Jersey Department of Environmental Protection and lives in Princeton, told an attentive audience about state environmental policy. During QandA, he was asked about the state's continued desire to dismantle the DR Canal Commission, despite compelling arguments and strong public support for its continued existence.

Afterwards, I led a walk around Mountain Lakes, pointing out various species, including this flowering bladdernut
and the woven bark of butternut (also called white walnut). Both of these species are rarely encountered in Princeton's forests, though there's an effort underway at Mountain Lakes to find and propagate native butternuts.

With the upper lake and dam restored, the lower Mountain Lake will be the focus of work this summer, as the dam gets rebuilt and enlarged, and the historic spillway is reconstructed from a jumble of rocks.
 In the meantime, the great blue heron is trying to go about business as usual.

Tuesday, May 10, 2011

Flying Seeds and Soaring "C"s

These are the days when seeds take wing, as a spring breeze sends the maples' winged achenes helicoptering across the sky. In the midst of this blizzard of genes searching for a new scene, I received a call from further down the piedmont, in North Carolina, where the 13 year cicadas are singing. My friend, sitting on his back porch, reported that they sound to him more musical than the calls of the annual cicadas. I could hear their drone in the background and checked the pitch on the piano. "C," I informed him, so he would know he's living through the time of the soaring "C"s.

Saturday, May 07, 2011

Tickling the Tiger's Belly

It was probably in my 20s when, in a dream, as I was riding in an open truck cab down a street in the neighborhood, a large wild feline--let's call it a tiger--ran up and leaped upon me. In the next moment, I and the cat had tumbled down out of the truck, the tiger had shrunk into a docile kitten lying on its back, and I was tickling its belly.

I thought of that dream this past Sunday as a volunteer and I plucked garlic mustard weeds out of a wooded slope near Mountain Lakes House. Volunteers have been pulling garlic mustard there for years now before the invasive plant has a chance to go to seed, and as the soil's reserve of weed seeds diminishes, our work has become progressively lighter. This year the pulling was easy, the soil soft from rains, the weeds scattered and few, which meant more attention could be paid to the peaceful spring morning, and the native diversity springing up all around--Pennsylvania sedge, solomon's seal, Jack-in-the-pulpit.

In a world often short on sense, with so much of nature thrown out of balance, I tend to look upon a rich gathering of native species as a refuge of sanity. What a pleasure to feel time echoing through that woods, our work made easy by those who had come before, surrounded by plant species that had achieved balanced association over millennia of co-evolution. This is a habitat restorationist's dream--a wild order relieved of past traumas, where the riches of a land's history speak to the future, and nature calls out for nothing more than a scratch on its belly.

Tuesday, May 03, 2011

Spotted Salamander at Mountain Lakes

Most of us haven't seen a spotted salamander. They shun the light, spending their time under logs and leaf litter. Some people have a knack for finding them, like the Princeton Hydro biologist who found one at Mountain Lakes Preserve, just up from the Upper Settling Pond. The pond was built in the 1950s, probably to catch sediment coming downstream before it could get to the upper Mountain Lake.

The pond did its job so well that it became filled with sediment, except for one section whose shallow water allows spring peepers, and apparently a few salamanders, a place to lay their eggs each spring. Wikipedia describes a symbiotic relationship in which a green alga lives in each clear, bubble-shaped egg alongside the developing salamander. The alga produces oxygen for the salamander, and the salamander in turn provides carbon dioxide for the alga with each breath. It reminds me of a miniature Biosphere--the three acre greenhouse in Arizona where eight people lived for a time, sealed off from the outside world, in complete co-dependency with the greenhouse plants.

Since the pond is going to be dredged, and the combination of fish and deeper water will not suit the needs of amphibians, a search began recently for places to dig vernal pools. We found places for three, including a field that once had a swimming pool. If all goes well, the frogs will still sing every spring, and there will still be a chance for the lucky few among us to find a salamander under a log.