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.

Parallel Prairies in Ann Arbor

Most summers in recent years I've traveled to Ann Arbor for a reunion performance with a jazz/latin group I've played with since 1983 called the Lunar Octet. It's also a chance to see my old neighborhood down along Easy Street, where our first house came with a beautiful garden of poppies, delphiniums, blue thistles, Miscanthus grasses and other perennials. These I loved and tended to, though by the time we headed to North Carolina my gardening interests had shifted strongly towards native plants. I have a friend in that old middleclass neighborhood who in many ways lives a life parallel to my own. Jeannine Palms leads the Wet Meadow Project, which in collaboration with volunteers and city staff has transformed much of the nearby sprawling turfdom of Buhr Park into native wet meadows designed to catch runoff. She often gets kids to help out, and calls them "superswampers."

The project is flourishing, with many of the prairie species we have, like sweet bergamot, and a few we don't see here in central NJ, for whatever reason.

Gray-headed coneflower is one of the midwestern species whose range doesn't quite extend to New Jersey. You'll see in the lower left corner of the photo some Queen Anne's lace, a non-native which Jeannine almost certainly works to limit in her wet meadows. It's a pretty flower, but a trip to the midwest makes one realize how it tends to take over in ways we have not yet seen in New Jersey. Other invasives of midwestern fields, like teasel and spotted knapweed, have yet to become extensive in the east to my knowledge, but it may only be a matter of time.

Some of my favorite prairie wildflowers are Silphiums that are much more numerous in the midwest, like rosinweed, compass plant, cupplant and prairie dock. The bright yellow flowers rise on tall stems out of the enormous basal leaves of prairie dock.

The towering Silphiums in the background are cup plant, a species that we now have in Princeton at the Riverside Elementary gardens and our Herrontown Woods botanical garden.

Along with some of the Silphiums, like the big leaves of prairie dock in the background, Ann Arbor's meadows also have some very attractive goldenrods that have the desirable quality of not spreading aggressively underground. Stiff goldenrod (not yet blooming in the foreground) is one of these, as is showy goldenrod.

During my visit this past month, I arrived late for one of Jeannine's workdays, just in time to find her walking home with a young assistant--a girl full of wonder at the natural world. They had been hanging some tallow soap in the Edible Forest--yet another patch of grass that Jeannine had transformed into a botanically rich oasis for the community. She had heard that the soap will deter deer. We saw a hawk land in the very top of a tall evergreen tree in the distance, making an insistent, plaintive sound that could have been the hawk's prey or the hawk itself. We wondered whether it might have a nest there. When it flew over to a a telephone pole, a rodent hung from its talons--all part of a food chain that Jeannine nurtures with her native wet meadows.

The Very Dramatic Caterpillar Eating Wild Blueberry Bushes

Before I saw the blueberries, I saw the caterpillars eating the blueberry bushes. They were distinctive in the braiding of their bodies into a cluster on the stem. I snapped a photo of their distinctive black heads, yellow necks, and striped bodies, and must have brushed against the bush, because when I looked at them again, surprise!

They had all contracted their bodies into a dramatic pose that completely hid their heads, as if they were the caterpillar world's equivalent of a synchronized swim team. What's the logic here? Look down and away and the potential threat will disappear? Seems human, somehow--a caterpillar's artistic pose to symbolize society's head-in-the-sand response to climate change.

A nearby bush had been stripped of leaves but still had a few blueberries.

While highbush blueberry bushes tend to be solitary, the lowbush blueberries I have seen in woodlands, whether in North Carolina, on top of New Jersey's Mount Tammany, or in Princeton's Herrontown Woods grow clustered in colonies on a hillside.

These heavily shaded patches and the measly crop they bear seem to me stunted remnants of a past glory, when periodic fires would sweep through, thinning the canopy and setting the stage for a burst of new growth from the resilient roots of the blueberries, which then prospered in the partial shade of the scattered trees. Thick bark and decay-resistant leaves are common traits of trees that are adapted to periodic fire. Oaks exhibit these traits in Princeton, their leaves persisting on the ground as fuel for fires that no longer come.

The most dramatic example of the distortion caused by fire exclusion that I've witnessed was in a woodlot preserved as part of Bennett Place, a Civil War site in Durham, NC where the war's largest surrender took place. In the past, trains passing close by would throw sparks, causing low-burning fires to sweep through the woodland, promoting the growth of fire-adapted post oaks and shortleaf pine. I like to call these rejuvenating events "mildfires"--the relatively tame wildness of a healthy nature--in contrast to the destructive wildfires we're used to hearing about in the news. The woodland--perhaps more like a savanna--was a favorite place for Duke University botanists to find a rich understory of wildflowers prospering in the open shade. As they remarked on this or that rare species of wildflower, they must have sampled the berries from the broad patches of blueberries that persist there. As trains have become less sparky, and people more fire-averse, the less fire-resistant, fast-growing trees like willow oaks have grown up, while the deepening shade and the accumulation of unburned pine needles have stifled the wildflowers. The once-thriving "fire-climax" ecosystem is begging for a fire that never comes, as the old trees slowly succumb.

Though the exclusion of periodic fire has also made Princeton's woodlands less natural, we can see in the caterpillars' partial munching--some shrubs eaten, some not--the persistence of another aspect of balance in nature, worked out over millenia of coevolution. No species can survive long if it wipes out its food source. Long-term stability thrives on balance. New species introduced from other continents lack these elaborate checks and balances. Stiltgrass smothers large swaths of Princeton's preserves because nothing eats it. Our forests have suffered a series of shocks, from chestnut blight in the 1920s, gypsy moths in the 1970s, and now the emerald ash borer--all from introduced species that lacked the checks and balances that evolve over time.

The common name for our very dramatic caterpillar, "contracted datana," is hardly a common name given how few of us have heard of it, and is merely an adaptation of its latin name, Datana contracta.  Come to think of it, the heads of the caterpillar look a lot like blueberries. Their collective ducking seems to be saying to a hungry predator, "Please move along, no food here!"

A Stream of Summer Flowers

A trumpet vine flower looks giant with Veblen House as a backdrop. It was a pretty sight to see a hummingbird visiting one.

Culver's Root draws clouds of pollinators of varied sizes.

A week or two before, the Culver's Root took on an upside down chandelier look during a brief drought.

Tiger lilies are an asian species found along Princeton's streets this time of year. A couple native species survive in the wild in our area, though nowhere in Princeton to my knowledge.

Here's a contrast between the native black-eyed susan

and a bred variety that puts on a big show but doesn't seem to attract pollinators.

Cutleaf coneflowers are almost as pretty in their bud stage

as when they open up.

The first of what will likely be hundreds of native rose mallow Hibiscus flowers in our garden, freshly opened and freshly chewed upon.

There are a few specimens of storax around, with its pendulant flowers.

One of my earliest interactions with plants was popping the buds of the hostas that lined our patio when I was a kid. If the buds are just at the right stage of development, they make a loud pop when squeezed. This type of hosta isn't very common in gardens now.

Common milkweed outside some classrooms at Littlebrook Elementary provided food for a bumper crop of monarch butterflies last year.

Purple coneflowers bloom for a longer stretch than most other flowers, which makes them so popular in gardens.

Lizard's Tail is a native growing along the shores of Lake Carnegie. It also does well in wet gardens.

Earlier in the summer, the tall meadowrue were attracting colorful hoverflies, which true to their name hover next to a flower before alighting. Send a photo of an insect to BugGuide and someone will quickly identify it for you. In this case, Allograpta obliqua, a common oblique syrphid.

The hoverflies did their job, judging from the abundant meadowrue seeds now forming.

A gathering of bucks grazing in the field at Littlebrook Elementary.

Deceptive Weeds

This time of year, you may see some plants rising in the garden that look like they have potential. Something about their form makes you hesitate to peg them as weeds and pull them out. Maybe, you think, it's better to wait and see if all that growth yields a substantial flower. Here are some weeds that have fooled me into a wait-and-see at some point in the past.

Pilewort has a thick stem and strong vertical intent. It will give you pause because it looks like it's headed somewhere, which, it turns out, is mostly up. All that vertical ambition climaxes in a gangly jumble of small flowers that attract pollinators but lack color. The name comes from the white seedheads that look like cottony stuffing for a mattress. If left to scatter, they will give rise to many more plants to be pulled the next June.

Pilewort - Erechtites hieracifolia - Aster family

Willow herb has a nice form, but can get weedy in wet soil, and the flowers are too small to create a visual effect.

Northern Willow Herb

Epilobium glandulosum

A member of the borage family, this plant, too, has an attractive form that looks like it could generate an attractive flower. If you leave it in, you'll end up instead with a bunch of stickers to pick off your clothes. Appropriately enough, it's called stickweed.

Stickseed
Hackelia virginiana
Borage family (Boraginaceae)

Mugwort has a nice resiny odor to the crushed leaves, and looks like it could grow an attractive flower, but doesn't. Instead, its capacity to spread underground to form dense masses makes it a threat to any garden. The cardboard box in the photo will be laid flat to smother the weeds.

There are Bidens with very showy, sunflower-like yellow flowers that bloom along Quaker Road later in the summer. And then there is the Bidens species that somehow made it into my garden, which produces flowers that lack any show at all. We had the showy species flourishing along a bike trail in Durham, NC. Gorgeous, but it grew so enthusiastically that it started obscuring the trail. Though it reaches great size, Bidens is an annual and can be easily pulled.

Even though I know that lambs quarters doesn't make showy flowers, the plant fools me each year into thinking I'll get around to eating its tasty and nutritious leaves. Generally, I forget, but this year my younger daughter used some in a red lentil soup that was delicious. An annual, lambs quarters can be abundant one year, hard to find the next. Like pigweed, it can get enormous in abandoned plantings.

When pulling weeds, pull low and slow, so the roots come out. Weeding teaches the gardener to be strategic. Humans tend to have little time, while the weed is dedicated to growing and spreading 24/7. Best to weed when the soil is soft, to get the roots, and before the weeds go to seed. To keep them from rerooting, best to drop them where the roots won't touch the ground, and where the sun can dry them out.

Entomologist Rachael Winfree Offers Advice on Catering to Bees

Some time back, Rachael Winfree, an entomologist at Rutgers, generously agreed to meet with us at the pollinator garden we're creating at Herrontown Woods, to discuss ways it might better fill the needs of bees. For an hour, she poured out information while I scrambled to take notes. More can be found at her website, at the bottom of this post.

DEAD WOOD: Her first thought was that she liked all the wood strewn about, in the form of trees felled by wind and ice storms over the past ten years. The bodies of trees live a long life after death, providing a home for all sorts of insect life. Fallen trees are one of the places bumble bees make their nests underneath.

SOIL: She liked less the soil--mostly heavy clay. The many kinds of bees that build their nests underground prefer looser, more sandy soil. Perhaps we could bring some sand in to lighten up some areas, she suggested, or dig up the soil here and there to make the bee's job of digging easier.

SLOPING GROUND: Slopes would be good, too. Water runs off a slope better, so there's less chance that the bee's underground home will be flooded. Our pollinator garden has no hills, but it does have the hillocks made when a tree is uprooted. The rootball angles up into the air, leaving behind a hole in the ground with slopes on all sides. America, it is said, was very lumpy back before western settlement, as each tree over the millenia would eventually fall, its raised rootball leaving a depression.

XERCIS SOCIETY: She mentioned the Xercis Society and its website on multiple occasions. She's on its board, and thinks it's one of the best sources of ideas for creating habitat for insects.

WASPS VS BEES: Wasps visit flowers not to collect pollen but to sip enough nectar to get through the day. They are therefore poor pollinators, since they don't collect pollen and therefore are less likely to spread pollen from one flower to another. To reproduce, they prey on other insects, which they collect and use to nourish their young.

BEES ARE VEGETARIANS: Bees are essentially vegetarian wasps. They use the protein in pollen to feed their young, collecting a bunch of pollen and then laying an egg in it. Different bees carry pollen on different parts of their bodies. The classic honey bee, the cow of the bee world, not native but widespread in the service of agriculture, carries pollen on the back legs, as do bumblebees. One bee carries pollen on its belly, which is very cute to see when one turns the bee over.

SOCIAL VS SOLITARY BEES: Social bees, such as honey bees and bumble bees, are in the minority. Most types of bees are solitary. These types are very unlikely to sting, because stinging is a very dangerous activity for a bee, and a solitary bee is on its own. Bumble bees and other social bees are "on the wing" longer than solitary bees, meaning that they are around all summer rather than for just a couple weeks.

BEES IN DECLINE?: Though the news media has been reporting that bees are in decline, Rachael contends that there isn't all that much evidence to back that up. There are no long-standing studies of bee numbers to reference. Complicating any effort to tally bee numbers, there are only three taxonomists who can identify all 160 or so species of native bees in New Jersey. (I didn't catch the names, but two of them may be John Ascher and Jason Gibbs. When googling John Ascher, I came across this very useful looking manual: How to catch and identify bees and manage a collection) Bees, unlike plants, must be killed in order to be identified, and though some of that is necessary for research, it's not necessarily an activity entomologists want to promote. Bees may actually benefit from the habitat fragmentation that comes with suburban sprawl.

SPECIALIZED BEES: I had wondered if there are specialized bees that depend on a particular plant species that we could then plant to help that bee species. She mentioned two to get me started: a bee called Andrena erigeneae that feeds exclusively on spring beauty (Claytonia virginica), and the Rose-mallow Bee (Ptilothrix bombiformis), which has a black velvet appearance and feeds on Hibiscus. (I found this informative article that lists many others: https://vnps.org/specialist-bees-need-special-plants/)

SMALL CARPENTER BEE (Ceratina sp.): a common bee around here.

NESTING: Bumble bees nest under logs, or at the base of bunch grasses.

MOBILITY: Small bees fly only a couple hundred feet.

PLANTS TO ATTRACT BEES: sweet bergamot, lavender, mountain mint--especially Pycnanthemum tenuifolium

MORE INFO: Her website has useful pdfs, including a primer on New Jersey bees.

Repopulating the Community With Native Wildflowers

My younger daughter Anna recently returned from a year in Bolivia, and since she loves to walk, we headed out across town towards Mountain Lakes. It gave me a chance to check out, or check in on, some of the plantings I've been involved in creating over the years. It was surprising how many we encountered along the way. There are the rain gardens adopted at the Westminster parking lot, plantings on both sides of the high school, a couple gardens around Mountain Lakes House, and then on the way back we stopped by the courtyard behind the Community Park Elementary, where I recently helped a bit with a garden planted by students under the leadership of Georgette Stern. Those are projects west of my house. Extending eastward are plantings at the Whole Earth Center, Smoyer Park and a botanical garden being established at Herrontown Woods.

Since many of the plants now in public places come from my backyard, or in many cases "through" my backyard from wildflower seeds collected from native populations along the canal, there are recurrent themes.

A pollinator flying around town will encounter these bottlebrush buckeyes in my yard, at Mountain Lakes House, and now at the botanical garden at Herrontown Woods.

These backyard clouds of tall meadow rue were first found along the canal, then traveled to my yard and from there to the various gardens around town. The new populations are particularly important because the original patch along the canal is being grown over by invasive porcelainberry vine.

Virginia sweetspire came from a nursery, but creates suckers that can be easily dug and transplanted to public places.

Divisions from these backyard oakleafed hydrangias have also become ambassadors of native beauty in the community.

The richweed in the front left of this photo is a rare native that first arrived in the backyard via a plant rescue from a stream restoration site on the university campus. Though it doesn't have showy flowers, the hydrangia-like foliage makes an attractive massing in a flower bed. Again, the backyard was a conduit, as the richweed's seedlings are now growing at Herrontown Woods.

Some beebalm given to me by a friend mixes with the tall meadow rue from the canal.

Division from that beebalm now thrive at the Herrontown Woods botanical garden, protected from the deer by some fencing.

Sundrops, here mixed with deer tongue grass--a common native grass in local floodplains--also made the journey from backyard to botanical garden,

as did cupplant, a giant wildflower here catching rain in its "cup." This is probably the tenth or twentieth generation from the original plant rescued in 1994 from next to a dumpster behind Mark Twain's house in Hartford, CT.

Fox sedge is a common local sedge that has an attractive shape that works for informal gardens.

A more recent find is purple milkweed (distinct from common, swamp, green, butterflyweed, etc.), a few specimens of which are now traveling from their original location at the Veblen House grounds to begin growing elsewhere in town.

Others have yet to travel, like black-eyed Susan,

and Queen of the Prairie (Filipendula rubra), a native I've never seen growing in the wild, given to us by a friend our first full summer in Princeton, when the 17 year cicadas were having a look all around.

The purpose of this post is not to encourage people to dig up plants from their gardens and spread them indiscriminately throughout town. Given how weeds can travel in dirt, I'm careful to introduce to new areas only seeds or bareroot plants, with a strong preference for local genotypes rather than bred varieties. The goal that began this process was to make isolated remnant populations of this or that native species less isolated and more resilient by starting new populations in auspicious conditions elsewhere in town.

There's a long-standing irony that the wildflowers native to an area are often the least encountered by people living in suburban landscapes dominated by non-native plants. This process of seed collection, division and transplanting, natural to a gardener, can help bring back some native diversity in the community, for people as well as pollinators to enjoy.