Some Summer Gardening Success at Princeton Schools

There can be a tendency for school gardens to suffer neglect during the summer, but many in Princeton are doing surprisingly well. There are the gardens on the grounds of Riverside Elementary that are best known and continue to flourish, but quite a few others as well. Behind Community Park Elementary, there was a wildflower garden in the courtyard behind the school that over the years got taken over by the most aggressive wildflowers--sunflowers and goldenrods, which have those strong rhizomes that other wildflowers can't compete with. This year, a friend and CP parent, Georgette, decided to renovate the garden and asked me to co-teach an after-school class for the purpose. After a lot of work, some of it done by the kids, who went at it with considerable zest and confidence, the garden now is transformed, with hills of corn planted Indian-style, a tipi trellis for string beans, a few wildflowers and switchgrass from the original planting, and some unusual crops,

like cotton,

and amaranth. The quinoa, not shown, looks a lot like the amaranth, which makes sense since they are both in the Amaranthaceae family. It was interesting to discover that a common edible weed in our summer gardens, lambsquarters, is in the same genus as quinoa: Chenopodium.

Some of the weeds at Community Park, as the photo shows, are hard to reach (hope that's not evidence of some serious deferred maintenance),

but we did manage to pull out enough foxtail grass, pilewort, and velvetleaf (photo) to get the intended plants ready for the opening of school. The velvetleaf, by the way, is in the same family as cotton, the Malvaceae, as is the native Hibiscus in the wetland below.

Now's a good time to take a stroll down Walnut Street and stop by the Princeton High School ecolab wetland. Native hibiscus, joe-pye-weed, wild senna, giant cup-plant all are at a perfect height for viewing from the railing. I was over there the other day and happened upon a woman holding a large bouquet of flowers (bought, not picked from the wetland) and a young man all dressed up and serious, who appeared to be proposing. A proposal of marriage next to our wetland? I think we're onto something with this wetland garden thing.

The wetland was completely unfazed by the recent heavy rains. I just hope the school survived. This fan on the wooden performance stage brings back memories of the flood damage a couple years back, but a sign said they were waxing the floors.

And behind the highschool, the gardens may not be proposal-worthy, but a few of the raised beds are in good shape. Though the bed on the right shows how foxtail grass will take over any bed that's not cared for, the native cutleaf coneflower (tall yellow flower) and New England aster we planted a few years back have expanded to two beds instead of the original one. Some angel gardener must be helping this happen.

The coneflowers in turn will attract more yellow in the form of goldfinches as the seeds begin to ripen.

Visited a month ago, Littlebrook Elementary has a fine crop of milkweed feeding the monarchs, and a nature trail that handyman Andrew Thornton has been tending to with the help of some sophomore volunteers.

A Whole Lotta Buddin' Goin' On

There's been an air of anticipation the past couple weeks as some of the biggest and brightest wetland wildflowers have been getting ready to bloom. These are some of the buds quickly developing in the July sun.

The first photo shows the buds of Joe Pye Weed.

Buds of Hibiscus moscheutos (Princeton's one native Hibiscus species)

Cutleaf Coneflower, just starting to open.

The beginnings of Boneset flowers, with pickerelweed in the background.

Photos were taken at the Princeton High School ecolab wetland, tucked inbetween the two new wings of the school on Walnut Street. If you're out for a walk, the wetland makes for a nice visit. There's a sidewalk all the way around it. The canal towpath, between Harrison St. and Washington Rd. is another great spot to see many of these flowers.

Manhattan's High Line a Ribbon of Native Plants

Native plant lovers have long faced a conundrum. If urban and suburban landscapes are so dominated by exotic flowers, grasses and shrubs, how will Americans ever encounter America's glorious natural heritage on a regular basis?

One spectacular way just became available in New York as of June 8. A section of the old, abandoned rail line on the west side of Manhattan has been refashioned as a pedestrian way planted with a rich variety of native flora.




The irony is pretty rich, too. You'd think that these native plants would need some sort of "natural" habitat to survive, but many of our natural areas aren't really natural anymore. Most of these plants would quickly die if planted in a typical nature preserve, where they'd wither in the dense shade or be eaten to the ground by overabundant deer. Trees and deer are natural, but we've banished the fires and predators that once held their density in check and allowed sunlight to reach the ground here and there.

The low-growing native species in these photos need sun, and they get it here, thirty feet above the streets of New York. In Princeton, the story is very similar. The native species that need sun are thriving in places highly altered by humans--along the canal and at Princeton high school's ecolab wetland.

Pollinator Talks at D&R Greenway

UPDATE: The Jan. 27 talk tonight has been postponed due to yesterday's snowstorm.

Two talks on the fabulous diversity of native pollinating insects will be given on January 27th (butterflies) and February 16th (bees) at the DR Greenway's Johnson Education Center, out Rosedale Rd, on Preservation Place. Both events start at 6:30. More info can be found here.

For past posts about all the wonderful pollinators that can be catered to by planting native wildflowers and shrubs in Princeton, try typing words like "bees" into the search box at the top left of this page. The butterfly in this post was feasting on mountain mint growing in the meadows at Tusculum. Projects I've been involved in through Friends of Princeton Open Space to provide habitat for pollinators include the high school ecolab wetland, a field at Mountain Lakes, and the marsh at Rogers Refuge.

Johnny Elderberrystem

When Johnny Elderberrystem had to remove a big pin oak tree in his backyard that was sitting on a drainage tile and shading his neighbor's vegetable garden, one thing he did with all that extra sunlight was, not surprisingly, grow some elderberry bushes. Johnny acquired his love for elderberries way back when, during jaunts with his parents each fall to harvest elderberries along the streams of Wisconsin. All those berries turned into delicious preserves and pies. Decades later, he learned that elderberry bushes, like buttonbush and silky dogwood, could be propagated by cutting a section of dormant stem in late winter and pushing it into the ground. Couldn't be easier. Johnny Elderberrystem was off and running.

And when those now ten foot high shrubs hold forth with disks of white flowers, Johnny knows it's time to venture out and see how all the other elderberries he's planted in Princeton over the years are doing.

This one in the raingarden at Mountain Lakes House probably grew from one of those live stakes he started in the greenhouse.

And this one along the Mountain Lakes driveway is one he planted and actually remembered to water through its first, precarious year. (You've got to wonder what sort of survival rate Johnny Appleseed got, planting apples here and there while he waltzed from county to county, leaving all those seedlings to the whims of the weather.) Other elderberries are living the good life at the Princeton High School ecolab wetland, their thirst well quenched by the sump pump's steady offerings.

This spring, Johnny Elderberrystem remembered to go down to the canal just west of the Harrison Street bridge, to mark elderberries with red tape so that the state parks crew that does the annual mowing of the fields there would mow around them. He missed one, and though new stems are popping up, they won't bloom and thus won't offer wildlife any flowers or berries to feast on. He did manage to mark about ten, though (he lost count at three, being easily distracted from counting) and the crew mowed around them, which means a little more dining pleasure for the pollinators and the birds.

Now, if only the birds could be trained to use the elderberry feast to bomb the visiting coxwains as they bark orders at their crews in ivy league regattas this fall, Johnny might be able to get some funding for all of this proactive stewardship.

Highschool Wetland in Full Flower

It's a good time of year for an evening walk along Walnut Street. The sunsets can put on a show across the sports fields, and the high school ecolab wetland is having one of its finer moments. These elderberry blooms are past, replaced by a good-looking crop of berries, but there's a resplendent wave of wildflower blooms coming on.

This is the view from the sidewalk. Music may be wafting out of the practice room to the right, mixing with the loose banjo string call of the green frogs.

The blue irises made quite a splash a month ago, and the soft rush (left) was looking stately.

But a larger ensemble is just warming up: wild senna, black-eyed susan, hundreds of joe-pye-weed, swamp rose, sunflower, and cut-leaf coneflower. What's particularly auspicious about this wetland's setup is that it is essentially surrounded by an observation walkway, perfect for viewing the wildflowers rising ten feet up from the wetland below.

Walk around the back of the wetland to get a look at the crayfish living in the small pool where the sump pump feeds the wetland with fresh water from the high school basement.

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

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

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

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

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

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

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

A New Invasive Plant at Princeton High School

Here's a story about how an invasive nonnative plant can be accidentally introduced and quietly transform an area. It also shows how invasion can be regional but also very localized.

This is a big picture of a little yellow flower called birdsfoot trefoil (Lotus corniculatus). The clusters of flowers and especially the subsequent seedpods resemble the shape of bird's feet, and the tiny leaves echo this shape to some extent.

I hadn't knowingly seen it much, and only learned the name a couple years ago, but this year, 

it has spread aggressively along the grassy extension along Walnut Street at Princeton High School. I'd noticed a few the year before, but now it is dominant along a stretch in front of the Performing Arts wing and the Ecolab wetland. 

This year also, it is coating areas of an old pasture next to Herrontown Woods. In the pasture, it was probably planted intentionally as forage for cattle, but at the school, it surely was introduced accidentally.

Should we be concerned about either example of this nonnative rampancy? I sent an inquiry to a couple listserves of land managers, and received a tepid response. Birdsfoot trefoil is mostly a roadside weed, was the sentiment. It only gets a couple feet high, so will likely just stay in the background rather than stifle native species. 

But I have a vivid memory of a prairie walk I went on last year at the Kishwauketoe nature preserve in my home town in Wisconsin. At one point, leading us through a gloriously restored prairie, the botanist spotted a birdsfoot trefoil and immediately went over and pulled it out. Was it merely a pet peeve, or was his determination rooted in past observations of dramatic consequences if birdsfoot trefoil is allowed to spread? 

This short video shows how birdsfoot trefoil can alter the appearance, if not necessarily the composition, of a meadow:

I did a quick survey of school grounds and the nearby neighborhood by bicycle, and discovered that the infestation is limited to grass next to the extra wide sidewalks that were installed along Walnut Street a couple years ago. It probably hitchiked in on machinery or soil used in construction of the sidewalk. Another possible vector was the planting of new street trees right where the birdsfoot trefoil growth is now the most dense. Rootballs, topsoil, tools, heavy equipment--all can carry weedseeds.

This is an invasion that's in the very early stages, and could be easily nipped in the bud. For instance, I found a grand total of three plants on the middle school grounds. Five minutes of spot spraying with a selective herbicide now is all it would take to stop an infestation that will otherwise become intractable.

Another reason to take action is that it is poised to invade the new native meadow planting in the detention basin next to the tennis courts. In this photo, a few plants of birdsfoot trefoil grow just across the parking lot from the new native planting. Does the school want a native meadow, or a meadow that is thick with a nonnative species that appears capable of outcompeting many of the native grassland plants? 

Now, while the extent of the spread is limited, would be the time to take proactive action. 

Course Offered on Managing Runoff

For those interested in better utilizing runoff in the yard, this spring I'll be teaching a course entitled Managing Runoff in the Landscape through the Princeton Adult School, beginning April 11. Registration has begun. The course is in the Personal Enrichment section on their website, princetonadultschool.org, under "home".

Here's a description:

"Water flow in the landscape can drive decisions about what to plant and where. Wet ground offers a chance to grow some of New Jersey’s most attractive and low-maintenance native species. We will visit several examples in Princeton of using runoff to aesthetic ecological advantage, including projects the instructor has contributed to Rogers Refuge, Princeton University’s stream restoration, Harrison Street Park, Princeton High School’s Ecolab wetland, and constructed raingardens large and small. By studying these examples, participants will gain knowledge of native plants and ideas for managing runoff in their own yards."

Teaching 9th Graders About Invasive Species

I was invited by my daughter's 9th grade biology teacher, Alexis Custer, and her colleague Jayne Ricciardi, to come in and speak to four classes over the course of a day at Princeton High School. The subject, invasive species, is full of subtleties and contradictions. Plants are good. They're the producers, ecologically speaking, while we're among the consumers. And yet, some of the thousands of imported plant and animal species are wreaking ecological havoc.

Though our culture tends to associate destructive consequence with ill-intent, most or all of the destructive consequence of invasive species was unintended. For example, the burmese pythons now altering the ecology of the Everglades were introduced by pet owners who released their exotic snakes into the wild when they got too big to keep at home. The collective consequence of seemingly humane individual acts can undermine a whole ecosystem.

Adding to the irony, an overabundance of one of the most beautiful and iconic native creatures of our woods, the white-tailed deer, is magnifying the damage by eating primarily native species, giving the invasives a big competitive advantage.

A more positive side of the story is that people can have a positive, healing effect on nearby ecosystems, by restoring balance. Most satisfying was telling the students about the high school's wonderful ecolab wetland, which is fed by an "old faithful" sump pump that keeps the wetland wet year-round with groundwater steadily being pumped out of the school's basement, several stories below their classroom. It's a great example of how people can create rich, productive habitats for plants and wildlife by working with nature, rather than against it.

The kids were attentive through the 45 minute talks. School curriculums, when they teach ecology, often focus on distant ecosystems like the Amazon or the arctic. This was a great opportunity to introduce the students to the ongoing ecological drama waiting to be explored in the town where they live. I hope they get out and walk the trails leading through Princeton's many nature preserves.

And what a sweet thank you note came in the mail from all the kids!

Fall's Last Flowers

From the outside looking in, the Princeton High School wetland ecolab looks pretty spent, as it should by the end of October. But a few flowers are hanging on.


This post's second photo is of native black-eyed susan blooming on top of black plastic laid down to contain weeds in some areas.

Third photo is of Helianthus tuberosa, a.k.a. Jerusalem Artichoke--a strangely named native sunflower whose tubers were eaten by American Indians. It's now grown as an edible ornamental.


The pale blue flower in the fourth photo is mistflower--a native perennial that looks like an exotic annual that's sold at nurseries.
Though most flowers are lingering from the summer, the fourth photo shows marsh marigold, a spring bloomer that the weather apparently fooled into blooming in the fall.

In the fifth photo, red clover, a good example of an exotic species that doesn't take over.

The last photo shows not a flower but the color of silky dogwood, a native shrub often found in the wild.

Joe-Pye at Princeton High

On lazy summer days, music wafting out of the Princeton high school's music rooms mixes with the plunky sound of green frogs in the wetland ecolab. With a science wing on one side and the performing arts center on the other, the flower-packed wetland serves as translator of biology into music.

Joe Pye Weed is looking highly floristic right now, and if you look closely at the shapes of the flower heads you'll see two kinds. The more flat-topped is probably spotted Joe Pye Weed (Eupatorium maculatum).

The more rounded, graceful flower head is hollow-stemmed Joe Pye Weed.

Here are the contrasting stems, with the hollow stem on the left.

Also in bloom now are a native sunflower (photo), swamp milkweed, cardinal flower, cutleaf coneflower, rose mallow hibiscus, wild senna,

 wild rice,

 water plantain, whose flower heads are so diffuse they seem impossible to photograph,

and boneset.