Part 3 of Making Gardens Last--Westminster Parking Lot

Neighbors on Linden Lane fought hard a couple years ago against the expansion of the Westminster Choir College parking lot. Seeing water collect in the open field, I had often thought it would make a great wetland garden for all the beautiful native species that prosper in wet ground. Despite arguments to the contrary, the parking lot was built, but because of stormwater regulations, some of the land was devoted to receiving runoff from the pavement in a small scale version of what I had imagined. In this first photo, a native wildflower seldom seen in Princeton gardens, Blazing Star (Liatris sp.) was planted in a large raingarden that serves as buffer between pavement and neighbors. It's bizarre to see crew members armed with weed whippers tending this planting, but they somehow manage to keep the grass down and the blazing stars up.

Two other raingardens, though, running in narrow strips between sections of the parking lot, have been left to grow up in weeds that hitchhiked in with the trucked-in topsoil. Blazing star and cardinal flower are blooming just as the landscaper's plans had envisioned,

but most are lost in the ocean of weeds and will likely be killed if the competing weeds aren't removed.

The weeds can be an interesting field trip in and of themselves. Horse weed is a native that grows tall and gangly.

Haven't seen pigweed much around Princeton, but obviously it's flourishing wherever the topsoil came from.

Smartweed (Polyganum sp.) often has what looks like a thumbprint on its leaves.

This weed, Queen Anne's Lace, a.k.a. a wild version of our carrot (Daucus carota) is ornamental. It's not native, and can get rambunctious in midwestern prairies, to the point of displacing native species, but has not been particularly invasive hereabouts.

If you look closely at the middle of the plate of tiny flowers, you'll find a purple dot.

Despite being of some botanical interest, the weeds dominating 2/3rds of the parking lot plantings are not what the original plan called for.

The Westminster parking lot planting is a good example of how native plants and the use of raingardens have become integrated into requirements for construction, but the maintenance side of the equation has not caught up. Maintenance, despite determining the ultimate success or failure of a planting, is given low priority, and ill-trained crews often end up doing more harm than good. The right plants go in, for the most part, but if they aren't knowledgeably maintained, you'll still end up with a failed planting, a lost investment in beauty, and a reversion to a boring trees n' turf landscape.

(Photo shows a Clethra alnifolia competing with the weeds.)

Chain Saw Gardening--the Sequel

A couple weeks ago, after witnessing the now neglected gardens planted at Harrison Street Park three years ago, I walked over to the Whole Earth Center, where a man was trimming the raingarden with a chainsaw. I didn't ask him to pose for a photo, but you can see plant debris littering the sidewalk.

A clipped bit of soft rush, no match for a chainsaw blade, was being held up for examination by the resident frog. It seemed inauspicious, that a garden I had installed a few years back was being given the chainsaw treatment. It happened last year with another raingarden down the street. But this time around the chainsaw treatment didn't go much beyond trimming back some of the native mistflower that had been leaning out over the sidewalk.

Strange to say, this garden is actually prospering despite the complete lack of coordination between the various entities who care for it. There's the crew hired by the out of town landlord, which lays down fresh mulch in the spring and this year added the chainsaw to its arsenal. In addition, there's someone on staff at the Whole Earth Center who does occasional watering, and then I stop by when I think of it, adding a few plants here and there. Some of what I plant gets smothered by the mulch, or gets pulled out unwittingly by the landlord's crew, but actually communicating with the other caretakers would be harder than dealing with the periodic setbacks.

Its success comes also from an auspicious hydrology. Roof water, which normally would go directly from the downspout out into the street, is instead funneled through a perforated pipe running just underground along the garden's full length. This extra dose of water allows the fringed sedge, soft rush, buttonbush and mistflower to prosper.

Before this was a garden, it was an elaborate sculpture of wooden stumps and logs installed by Peter Soderman. From what I heard, the fire officials took exception to all that wood next to a building, so only a couple pieces remain.

If I had thought of it, I might have suggested the man with the chainsaw trim back the pre-flowering stages of cutleaf coneflower and boneset on either side of the flowering oakleaf hydrangia. They'd simply bloom a little later, and be less likely to flop over. But who knows what a little encouragement would cause him to do next time.

Comeback Chestnuts and Butternuts in Princeton

On the 7th day of the 7th month, when the Brits via Andy Murray came back after 77 years to reclaim the Wimbledon men's tennis title, I took a hike with arborist Bob Wells to see some of the comeback kids he had found along the Princeton Ridge, in the form of native chestnuts and butternuts. Bob had recently conducted a tree inventory for Princeton, completing the township portion that can then be merged with the borough's. Along the way, he found a chestnut and a couple butternuts--species that have been laid low by introduced diseases. The number of naturally occurring specimens known to still be growing in Princeton can be counted on one hand.

I found Bob sitting in the woods near Bunn Drive with his dog, Mongo. While waiting for me, he had counted 21 woody species around him, a testament to the Ridge's diversity. Multiple kinds of hickories, maples and oaks, a beech tree, ironwood, cherry, tulip poplar, black birch, sweetgum, two kinds of Viburnum, witchhazel--learn to identify trees and you'll never be alone in the woods.

One of the other species was a solitary American chestnut tree of 6 inch diameter,

its distinctive leaves backlit by the afternoon sun.

One branch appeared already to have succumbed to the blight that laid waste this once dominant species of the eastern forests. The species as a whole went underground, its roots surviving, sending up suckers that would in time be killed off by the blight. Bob wasn't sanguine about this particular tree's chances, but at least it's still there, a century since the species was stricken by imported disease, still growing towards the sun.

Our next stop was further up the road, where clearing for the new Westerly Road Church had left a tall, gangly butternut out in the open. Though the native butternut (Juglans cinerea), also known as white walnut, was never a dominant species, and Princeton is on the southern edge of its range, its numbers have been reduced still further by an imported fungus.

Bob double checked the book's description. Thirteen leaflets, positioned opposite and stalkless, fit well,

and the dark brown pith. The trunk being hollow, Bob wasn't too optimistic about this tree's longterm chances, either, but to find a survivor is always reason for hope.

Heading around the bend onto Herrontown Road, Bob pointed out the thinned out foliage of a number of ash trees. Ash dieback, ash decline, something's going on with Princeton's ashes, and not much is known about the cause. Thinking it might be the arrival of the Emerald Ash Borer, the Asian insect accidentally introduced into Michigan that has been devastating ash trees on its way east, Bob arranged to have some traps set in the area. Results were negative.

To know and love trees is to realize that we cannot take our forests for granted, that behind the facade of static green is a shifting drama of competition, predicted demise, potential comeback, and mystery as engaging on its time scale as any sport. People play negative or sometimes positive roles in this high-stakes game. The easy accident of introducing a new disease to America is followed by a very long and hard struggle to save the species that are then pushed to the brink.

Our last stop was Autumn Hill Reservation, where Bob led me to a healthy butternut back in the woods, with room in the canopy to grow. I thought I saw another some 100 feet further off the trail, with impenetrable brush impeding our effort to confirm.

The bark of a butternut has a distinctive weave to the ridges. As you can see they've been known to sport a green trail marker, though they receive less compensation than famous athletes with product logos attached.

A few days later, I showed these trees to local nut tree expert, Bill Sachs, who has been growing and reintroducing American chestnuts and butternuts in various Princeton parks. He had located three butternuts growing naturally in Princeton, two of which have since been lost--one to a chainsaw, the other to flood and wind. Bob's discoveries bring the number back to three, plus all the seedlings Bill has grown.

We loppered our way through the invasive brush to reach what I had thought was an additional butternut 100 feet off the trail. A closer look proved it to be a black walnut.

Butternuts need more than one tree in order to bear nuts. The hope is that these few survivors have some level of resistance to the attacking fungi, and if we can start new groupings of these trees that will then bear seeds, these species can be coaxed back from the brink, to take their rightful place in Princeton's future.

Harry's Brook's Milky White Mystery Solved?

There's been a possible breakthrough in the case of the milky white color observed in Harry's Brook on June 20.

Reader Bill Sachs, better known for his work to bring the American chestnut back to Princeton, suggested the following: "If this hasn’t already occurred to you, chances are someone emptied the remains of a can of white water-soluble latex paint (or cleaned their brushes and emptied the wash water) in a drain connected to the Brook. The pigment in white paint is titanium dioxide… and it doesn’t take much to create a milky-white suspension. Easy to analyze for, too."

Other possibility:

I passed this idea along to Amy Soli of the StonyBrook-Millstone Watershed Association, which has long been active in monitoring water quality in Princeton's streams. She had been suspecting an algal bloom "that was short-lived in duration", judging from the floc in the sample that I had given them.

My less than ideal sample of the milky water:
She added that the sample "really couldn't be analyzed for anything as the sample was old, wasn't preserved, and was in a plastic bottle (many things can bind to plastic, which is why glass is preferred for most parameters- pathogens and a few other parameters are exceptions). We did consider runoff of sediments but could not identify any construction areas nearby that could have contributed light colored sediments (do you know of any in the area)."

Supporting the paint possibility: Amy said that "the paint theory is a pretty good one. We still have the sample. I can't test it for titanium dioxide, but I can see if one of our labs can do so."

Online data on Harry's Brook's water quality:
You can go to http://thewatershed.org/science/stream-watch/ to explore data on Harry's Brook, going back quite a few years. Most noticeable is the high levels of phosphorous. There may be additional data from the "Water Ambassador" water quality testing program on the state DEP site.

Thanks to everyone who has helped thus far in making sense of this pollution. Lots of pollution is invisible, and I've also heard word that the underground section of Harry's Brook extending upstream to Spring Street may be getting significant infiltration from leaky sewers in the oldest part of town. If so, this sort of pollution is having downstream consequences, as Harry's Brook empties into Lake Carnegie, which in turn feeds the Millstone River.

Backyard Conversation in Color

The days are hot. Deluge has given way to searing sun. Tall meadow rue casts clouds of white.

 Beebalm holds a parade in tattered red.

Buttonbush offers up golf balls from the water trap,

but the lawn chairs say, "Hey, take a load off. Sit back and listen,"

while the daylilies proclaim "Princeton!",

and the ducks say "Quack!"

Would-Be Shrub Lacks Wood

Ever wonder what a shrub would be without wood? It would be a would-be shrub, better known as a vine

that in this case goes by the name Japanese honeysuckle, which years back grew up and over a real shrub that eventually succumbed to the suffocating shade and began a slow-motion collapse under the weight of the vine's boa-like envelopment. It really can be seen as a form of digestion. No doubt the vine has been prospering on the nutrients slowly released by the decaying shrub infrastructure within.

I doubt that anyone at the Senior Resource Center on Spruce Circle even noticed what the vine would, could, and did.

Harrison Street Park Landscaping Threatened

From time to time, the monotony of trees and turf  in town landscapes triggers the impulse to plant native gardens in public spaces. Such was the case with Princeton's Harrison Street Park 3 years ago, when some $30,000 of native plants were installed as part of this formerly borough park's renovation. Ideally, plantings like this can make static landscapes more beautiful and dynamic, reduce runoff by replacing shallow rooted grass with deeply rooted perennials and shrubs, and provide food and cover for wildlife, particularly beneficial insects like pollinators. There's also the chance that adults, at loose ends while their children play, and kids exploring the park, will notice some of the native diversity and take an interest.

But the one-time act of planting is not the same as the long haul of tending, much as a one night stand differs from a marriage. Neighborhood volunteers worked heroically the first season, in 2010, to keep the plantings alive. (Is it pure coincidence that an ambitious planting of native plants always seems to be followed by a horrendous drought?). The success of that first season, critical as it was, still leaves all the years that follow. With municipal funding often skewed towards capital improvements rather than long term maintenance, who will maintain the plantings, or, more to the point, who will care enough, love them enough, or otherwise be paid enough, to be there dependably, knowledgeably, energetically, to safeguard the initial investment and intervene before problems spin out of control?

That question has thus far remained unanswered, as the well-known botanical bully mugwort mugs the intended plants in one bed,

a summersweet shrub struggles to find light amidst towering Canada thistles in another,

weedy grasses overwhelm whatever plantings were meant to occupy the berm next to the swingset,

and a volunteer silver maple seedling juts awkwardly out where low wildflowers were meant to ornament the entryway.

Even these few plants that are well-mulched and free of weeds have a sea of ground ivy headed their way.

"All natural", one might say, as one cites Darwin's survival of the fittest and eases back into the easy chair of indifference. But a town park is not a healthy ecosystem with all the complex components needed to maintain balance. It's a rigged game from the start. The soil is full of seeds of plant species that evolved on other continents and left all their checks and balances behind when they were brought here. One can make educated guesses about which native plants will grow best where, but without ongoing t.l.c. the weeds will take over and the beds will eventually be mowed down, bringing back the trees n' turf landscape that neighbors said they didn't want.

The lack of needed attention points to a longstanding gap in municipal staffing. As far as I know, not one parks maintenance employee can identify even a few of the native plants installed at considerable expense in Harrison Street Park. The town has an arborist, police, teachers--all trained to nurture and maintain a positive and conducive order among, respectively, trees, adults and children, and yet when it comes to the large majority of the plant world that doesn't have the good fortune to contain wood, we put someone on a lawnmower and tell them to have at it.

Maybe the newly formed Princeton parks commission can address this. Maybe there needs to be a skilled landscaper employed for enough hours to help organize and oversee volunteer days of the sort that kept the Harrison Street Park plantings alive their first summer. The more one stays on top of things, the less work it takes. In the meantime, a significant investment and a worthy approach to enriching the park experience is quietly being lost in a sea of weeds.

Garden Expansion and the Unpaving of the American Way

Most gardens are expanded by digging up more of the lawn. My friend Perry in Durham, NC took this approach to another level by digging up an unused portion of his driveway. There's a nice patch of sun above, and having a garden in front means that he can pull a stray weed and catch a taste of arugala on his way into the house. Last year's experimental wooden frame has been replaced by stone, and actually digging out the underlying asphalt.

The intimidating pavement turned out to be only one and a half inches thick, easily broken up with a pickax.

(Just as an aside, another friend once made an attractive walkway out of broken up asphalt.)

First in was the basil, which was immediately put to the test by torrential rains. A less paved American way means less flooding downstream.

Elsewhere in the neighborhood, a deturfed front yard featuring plantings, mulch and some memorable sculpture leaning against one of the town's many willow oak trees. In the photo are woodchips, but in this piedmont forest layered over a residential neighborhood, the narrow willow oak leaves and the big needles of loblolly and shortleaf pine make a fine self-generated mulch for yards, as attractive to my eyes as high-maintenance grass.

Milky White Mystery--The Sequel

Last week's post about Harry's Brook turning milky white has a sequel. Returning to the scene of the milky mystery with my canine assistant, Leo, I came upon two young men in waders, peering with great concentration at the contents of two plastic trays. The water in the trays contained what signs of aquatic life Harry's Brook might hold. Tom McKeon works for Americorps and is based this summer at the Stony-Brook Millstone Watershed Assoc., where he has the title Watershed Ambassador. Peter Zampella works for the Pinelands Preservation Alliance, south of here.

You can tell a lot about a stream by what sorts of aquatic life it holds. Some species are more sensitive to water pollution than others. Whereas a chemical test of the water will give a snapshot of the water quality that particular day, an inventory of the aquatic species able to survive there will reflect water quality over a longer period. Cumulative stress factors like low oxygen and periodic toxic spills will leave only the less sensitive species.

If there were toxins in whatever turned the creek milky white the week before, the more sensitive aquatic species might die off, and not show up in the samples of water Tom and Peter were scrutinizing.

As they do at the many other sites in the area that they monitor, they also measured water temperature, and did a rough calculation of water flow using a sophisticated device known as a rubber ducky. There are specially made floats for the purpose, but the rubber duckies work just as well or better.

Only rubber duckies with the proper paraphernalia need apply for the job. Peter explained that the ducks with goggles, etc. are a bit heavier, giving them the optimum density for measuring the speed of water flow.

Tom agreed to take my sample of last weeks milky water to the Watershed, where it could potentially get transferred to the state DEP offices for testing. We noticed that the white color comes from lots of white particles suspended in the water.

The water quality verdict? Not great, though not surprising, considering that the water comes from a network of pipes that drain Princeton's downtown business district.

Green Roof in Atlantic City

This "green roof" has been growing, or at least persisting, on top of the Atlantic County Utilities Authority for a number of years now. Funny thing is that the portions of it that are green--those blotches of white clover on the right--are actually considered a weed in this context, and should be taken out.

The brown areas consist of several kinds of sedums that despite their appearance are alive.

You'd think that a legume like white clover, which fixes nitrogen from the air and thus makes the soil more fertile, would be a good thing. But in fact there is a reason to keep the soil poor. A more fertile soil will encourage more weedy growth, which in turn will shade out the sedums and leave nothing but weeds. If a drought comes along, and  the weeds die out, the roof will have lost its vegetated cover. Low-fertility is actually beneficial in this situation, and likely has a lot to do with this roof being less weedy than others I've seen. Another reason to limit nutrients is that any runoff not absorbed by the roof will head into the local waterways through the storm drain system.

Rick Dovey, our tour guide (the tour was organized by Sustainable New Jersey), told us that the green roof has markedly reduced heating and cooling costs for the building.

Here are some sedums planted in what is essentially a miniature green roof, on the Mall near the Botanical Gardens in Washington, D.C.

Making Gardens Last, Part 1

Why does one wildflower garden thrive while another becomes weedy, unbalanced, and eventually gets mowed down? Here are some reasons why this garden at the corner of Linden Lane and Spruce Street has thrived:

• The plants are well adapted to this dry site. Butterflyweed (orange flower), threadleaf coreopsis (yellow), phlox (white), hosta and stonecrop (Sedum spectabile) are all well adapted to an upland location. If they grow well, weeds are shaded out.
• None of the species are aggressive spreaders, so minimal work is needed to maintain balance.
• The garden is in the front yard, so a mixture of pride and constant visual reminder insures it will get attention. Weeds will be caught early, before they become a big problem
• The sidewalk protects it on two sides from invasion by weeds like ground ivy and mock strawberry, and runoff from the sidewalk can provide extra water.
• Some lasting affection for the plants, or at least knowledge of which plant is which, and affinity is usually behind gaining that knowledge.

Harry's Brook Turns Milky White

Yesterday, Harry's Brook turned into Princeton's own Milky Way. The source of the pollution is difficult to determine, because every part of the creek upstream of the intersection of Harrison Street and Hamilton Ave. was buried long ago in underground pipes. You can see in the distance where the creek emerges out of the oval pipe, with the intersection just beyond. In another era, kids would seek adventure and cooler temperatures in the summer by exploring these pipes, which extend up towards Palmer Square, where this branch of the creek begins.

I took a sample of the water, and reported the spill to town engineers and the Stony Brook Watershed Association, which does periodic monitoring of the creek. These episodic spills, which may only linger an hour or two, don't show up in periodic water quality testing. There's been as yet no interest shown in testing the sample I took, which to the untrained nose had no telling odor. Hard to say whether it was serious pollution or of the "spilled milk" variety. Whatever it was, it will flow eastward down the length of Harry's Brook to where it empties into Carnegie Lake near Kingston.

Some of Princeton's other underground creeks--those that drain the Witherspoon and Guyot Street neighborhoods, and flow west to join the Stony Brook near Johnson Park School, emerge from pipes in Pettoranello Gardens, and they, too, sometimes have an unusual color. One spill I tracked back to periodic releases by the town swimming pool when it flushed its filters. (There may be a different protocol now with the new pool.) The timing of this Harry's Brook spill is worth considering, with perhaps some end of school year maintenance going on.

Anything poured into the street ends up in the local creek. And sometimes there are cross connections in which materials that should be going down the sanitary sewer to the wastewater treatment plant instead flow untreated through the stormwater system into the creek.

Those who saw Stephen Sondheim's fairy tale-filled musical "Into the Woods" at McCarter may wonder if Jack's cow Milky White miraculously started producing again, but given McCarter's location in the Princeton landscape, that gusher of mythical milk would have headed straight down to Lake Carnegie, far from Harry's Brook's meanderings on the north side of Nassau Street. Still, fairy tales don't necessarily need to obey local topography.

In any case, by today, Harry's Brook was back to its normal clear self, the only evidence of white being the bubbles from a small waterfall.

Note: See update at this link.

Roses and Rose Rosette Disease

Interesting to watch how rose rosette disease is affecting local roses. Both in the wild, where its impact has been beneficial in setting back the highly invasive multiflora rose, and in intended rose plantings, like those blooming at the John Witherspoon Middle School, the impact has been inconsistent.

Here, two bushes are so impacted that they haven't managed any blooms. They are framed by two shrubs that have resisted the disease thus far. What's good news for intended plantings (some specimens may survive or at least have a few more good years) could be bad news for land managers who thought the disease would do all the work of restoring balance and make our nature preserves far less prickly places.