A Great Video about Pollinators on Mountain Mint

Some wildflowers are much better at attracting pollinators than others. The two champions in my book are clustered mountain mint and boneset. Back in 2008, I started documenting the many kinds of insects and other creatures drawn to the boneset growing in my backyard. Little did I know that an entomologist friend I hadn't seen since Ann Arbor college days, David Cappaert, had been inspired to do the same, 200 miles away, with the mountain mint growing in a Hartford, CT schoolyard. 

Dave had the advantage of 1) being an excellent photographer and 2) actually knowing the creatures' names. He created a remarkable video entitled "Mountain mint, one day in August," in which he documents 52 species he found on one stand of mountain mint. The video is a parade of colorful creatures with colorful names like bee wolf, wedge shaped beetle, stinkbug, ambush bug, jumping spider, freeloader fly, and orb weaver. 

Particularly fascinating, at 8:20 in the video, Dave begins describing the many interrelationships between the pollinators and their predators and parasites--a wonderfully complex food web, all "fueled by the nectar of the mountain mint." Check it out, and if you don't have any mountain mint growing in your yard, come to the Botanical Art Garden at Herrontown Woods, where in early July it's just starting to bloom. 

 

Note: We also have another kind of mountain mint growing in the Botanical Art Garden: probably narrow-leaved mountain mint (Pycnanthem tenuifolium), which is the more common species found growing naturally around Princeton, but clustered mountain mint (Pycnanthemum muticum) is the champ when it comes to pollinators.

Bouquets and Backyard Diversity

I had an unexpected insight on Mother's Day about the advantages of having a wide variety of flowering plants growing in one's yard. It began with a few preparatory texts in rapid succession from my older daughter the day before:

"Mother's Day tomorrow"

"!"

"If you want to get flowers or something"

Responding to this imperative, my first thought was to go to the store and buy a bouquet. Then I thought again. I value the local store, and store-bought flowers can be pretty, but a little predictable, and do I really want to be supporting the transport of flowers flown all the way from Colombia, Equador, and Kenya? 

So, my thoughts turned to the yard, which thus far this spring had provided a fine progression of daffodils, tulips, and lilacs. But now, with Mother's Day upon us, all those easy ornaments for the indoors had faded away. A cynical thought came to mind, that the creators of Mother's Day had timed it to coincide with a gap in local blooms, the better to spur sales of flowers. 

But no, climate change has been altering the timing of blooms for a long time now. And looking back at a post I wrote entitled "Mother's Day's Complicated History With Flowers," I found that Anna Jarvis founded Mother's Day to correspond to when her mother had died, on the second Sunday of May. She campaigned for nine years to make Mother's Day official, then spent the rest of her life fighting against the commercialization of it by the florist, card, and candy industries. 

My instincts were right, then, to head to the backyard for a bouquet, but what to use? 

There, blooming in brilliant, lacy white along the fenceline, was a native fringe tree. That got me started. Add some Lenten Rose, daisy fleabane, and some leaves of sensitive fern, and ... Voila! 

The usual plug for planting flowers in the yard is to feed the pollinators. Since different species bloom at different times, adding more species better insures there will be a steady progression of blooms to sustain pollinators throughout the growing season. 

On Mother's Day, our fringetree saved the day, showing how backyard biodiversity can also feed human relationships and indoor ornament.

Various family members have brought the outdoors inside to make bouquets over the years. Most of the flowers are native, but not all. This one, from June, adds sprays of Virginia sweetspire and the yellow of sundrops and yarrow to roses. 

Lenten rose mixes well with iris.

Those floppy peonies in the yard can thrive indoors in a vase, perfuming the house.

This one from early September combines boneset, purple coneflower, obedient plant, "Autumn Joy" sedum, and Indian grass with a few sunflowers.

October brings goldenrod, New England aster, frost aster, and the deepening burgundy of sedum. Some of the wildflowers drop pollen on the table, but that seems a small price to pay.

Sometimes it's good to rock out with the sheer joy of sunflowers, given some subtlety by the goldenrod. Perennial sunflowers spread like crazy in a garden, so try your best to grow them in big containers rather than letting them loose in the flower beds. 

Even in November there's beauty to bring indoors. A botanist friend, Cynthie Kulstad, brought forest and prairie together for this bouquet at the 20th anniversary of a watershed association I started in Durham, NC. 

For many people, perhaps most, nature's diversity seems intimidating. Thus the countless static yards simplified down to turf and nondescript shrubs. 

You can see, though, that the intimidation of nature's endless creativity outdoors can be overcome, and ultimately inspire human creativity indoors. It all begins with digging up some turf and planting that first flower.

Botanizing With Seek at Indiana Dunes National Park

Things were going our way as we pulled into Indiana Dunes National Park. Swinging around the south side of the Great Lake on our way to Michigan from Chicago, we decided Indiana Dunes would be a good spot to see the shoreline. The cheerful attendant at the gate offered different options for admission. One was a $20 yearlong pass to all national parks for a senior like me. Now, that's a major perk for what still seems pretty modest longevity. 

A visit to the Chicago area offers a chance to see some wonderful restorations of the region's native habitats--prairies, oak savannas, wetlands, dunes--achieved over decades, in part through a consortium known as Chicago Wilderness. Bur oak savannas had disappeared altogether under a sea of nonnative buckthorn, and had to be recreated through botanical research, invasive plant removal, and the reintroduction of fire. 

It was surprising to learn that the Indiana Dunes, a product of receding glaciers and fluctuating lake levels that exposed sandy beaches to the wind, is the fifth most biodiverse national park, and is called the "Birthplace of Ecology." In 1986 Professor Henry Cowles of the newly formed University of Chicago started bringing his students to the dunes to study how a plant community develops over time. The dynamic dune landscape provided a gradient of stability ideal for studying plant succession, from the raw windblown sand of the lakeshore to the complex diversity of species growing on the older, more stable dunes further inland.   

Many of the dunes were mined and carted away long ago for sand. That any survive is a long story, told on wikipedia, featuring Chicago botanists and conservationists like Henry Cowles and Jens Jenson. Some credit for preservation is also due to a woman who in 1915 abandoned city life in favor of a shack on the dunes. Drawn to the spiritual power of the landscape, Alice Mabel Gray became known as "Diana of the Dunes", and advocated for their preservation. She's featured on the interpretive signage in the park.

"Her unusual, free-spirited lifestyle fascinated local townspeople and newspaper readers here and across the country, bringing national attention to the Indiana Dunes at a critical time of early conservation efforts."

Alice Gray's story triggers memories of Thoreau, and a character who lived on the beach in one of Steinbeck's novels--Cannery Row or Sweet Thursday. Thoreau spent two years at Walden Pond; Gray lived on the dunes for nine. 

For me, it was a chance to botanize. The pleasure of learning plants--their names, their shapes--is that you'll encounter the familiar no matter where you go. If you've gained some familiarity with the plant world, you'll find a lot of New Jersey in Indiana, and vice versa.

Look! There are the three shapes a sassafras leaf can make,

and the scalloped leaves of witch hazel. 

And for those plants I didn't readily recognize, I had an ambassador in my pocket, ready to provide an introduction. The phone app I use is called SEEK--a popularized version of iNaturalist. The fun thing about it is that you can point your phone's camera at a plant and the plant's name will appear on the screen. No need to take a photo. It's as if an ID label were hung conveniently on nearly every plant you pass by. 

This shrub, with its three leaflets and distinctive seedpod, reminded me of bladdernut (Staphylea trifolia)--a large native shrub that grows in only a few locations in Princeton's nature preserves. SEEK--my "pocket botanist"--called this dune plant Common Hoptree, Ptelea trifoliata. Turns out that bladdernut and common hoptree are related, being in the same Order: Sapindales.

The pine trees perched on the dunes looked familiar, with their short, paired needles. SEEK, with infinite patience, reminded me: Jack pine. I read about them fifty years ago when first discovering the elegance of fire ecology. Jack pines have serotinous cones that only open when heated by a fire sweeping through. The seeds then fall on the mineral soil ever so conveniently left exposed and fertilized by the flames--yet another clever adaptation of plants to periodic fire. In the midwest, and even in New Jersey, the reintroduction of fire into the landscape, in the form of controlled burns, has been an important element in the restoration of habitats like prairies and oak savannas.

SEEK reassured me that this was in fact winged sumac, just like the winged sumacs that have been spontaneously popping up as we restore the habitat in the Barden at Herrontown Woods. Maybe not "just like." The characteristics of a species can vary across its range, like accents in speech. 

There's a whole long list of invasive species that supposedly grow on the Indiana Dunes, but I didn't see any. What a great feeling to visit a habitat where native plants are thriving. The one weed I saw was the native horseweed. It can cover whole farm fields, but here one was growing all by its lonesome, as if on display, in a crack in the concrete. 

Another bit of luck: a threat of rain had kept the crowds away, making us one of the few witnesses to a beautiful beach and highly swimmable Lake Michigan water. Having arrived with no expectations, the beauty and a cool swim sustained us through the rest of a day of travel.

A few observations collected on the SEEK app:

Common Hoptree, Ptelea trifoliata

Tall boneset, Eupatorium altissimum

Shining (winged) sumac. Rhus copallinum

Flowering spurge, Euphorbia corollata

False boneset, Brikellia eupatoriodes

Native Plants Prosper in a Wet Meadow at Smoyer Park

A little video tour of a wet meadow habitat in Smoyer Park, Princeton, where lots of native wildflowers were planted and early intervention has kept invasive species from taking over. Part of my work at Herrontown Woods. 

 

 

The town helps out by mowing this basin once a year in late winter, and its deer culling program reduces the browsing pressure on the native plants so that many can bloom. This year, 2024, the basin was accidentally mowed in early June. Though traumatic at the time, the plants grew back, and the effect was to concentrate blooms later in the season. 

The detention basin was converted in 2016 from turf to native grasses and wildflowers by Partners for Fish and Wildlife. Ongoing followup by Friends of Herrontown Woods has added additional native species and prevented invasive species like mugwort, Sericea lespedeza, crown vetch and Canada thistle from taking over. Other aggressive plants that need to be countered are giant foxtail, stiltgrass, carpgrass, nut sedge, wineberry, blackberry, and pilewort. Native species being encouraged are big bluestem, Indian grass, various sedges, rose mallow hibiscus, ironweed, blue vervain, partridge pea, black-eyed susan, late flowering thoroughwort, boneset, monkey flower, buttonbush, and some goldenrods.

Ambush Bugs: Hidden Dangers for Pollinators

During an evening stroll in the backyard garden, with a big show of fireflies soon to come, we were admiring a common milkweed's blooms--like frozen fireworks at lawn's edge--when my friend spotted a honeybee on one of the flowers.

Isn't this the way it's supposed to be? You plant native wildflowers and the pollinators show up to feed ever so gratefully. But something didn't look quite right to me. The honeybee wasn't moving. 

Maybe it was memories of blog posts ten years ago--written after standing for hours gazing at the extraordinarily diverse community of insects and spiders drawn to boneset flowers--that caused me to take a closer look at that motionless honey bee. 

There, beautifully, mischievously, mercilessly camouflaged, hiding between the milkweed flowers, were two pairs of ambush bugs, mottled brown, black and white. The smaller of each pair sat atop the larger, apparently mating. Life is short for an insect, so it seems perfectly practical that one of the females, needing nourishment for whatever eggs come of the mating, had chosen that moment to snag the honeybee whose bad luck it was to visit those particular flowers.

Later, I returned to try for a better photo of the ambush bug and its mate.

By then, they had consumed what they wanted of the bee, dropping the remains to land ever so lightly on a leaf, one story down in the tower of milkweed.

Afternote: One could probably spend a lifetime exploring the mechanisms behind the camouflage of an ambush bug, as this quote from the Missouri Department of Conservation website shows:

"The colors of ambush bugs are worth mentioning. They can vary quite a bit within a single species. Most are gold, yellow, leaf-green, tan, brown, or white, often with dark mottled patches or bands. Apparently males are often darker or more spotted than females. It’s not clear whether individual ambush bugs change color like chameleons (and some crab spiders) to match the plants they’re resting on, or if they simply move to (or survive on) plants whose colors happen to match their bodies. It could be that they change color with each molt: young individuals, early in the season, being pale green, matching the new foliage of springtime, while older specimens become gold and black in later molts to match the flowers that develop in midsummer. The temperatures during egg stage may also affect the overall darkness of the insects."

PHS Ecolab Wetland Update -- Early June

The Princeton High School Ecolab wetland continues to bounce back nicely from its surprise defoliation last fall. 

If you pass by, you'll see the cattails that we're hoping to keep contained in one corner. The cloud of gray-green beyond is an annual grass planted by contractors as a cover crop, dotted with the deeper green of all the pre-existing native plants now re-emerging from their roots.

The ponds have water, despite the extended drought--sign that the sump pumps are now functioning again, delivering water from the school's basement up into the wetland. 

If you look a little closer, you may see some native blue-flag irises still blooming, happy as clams in this wet world.

On drier ground, the common milkweed is about to bloom.

Bindweed, in the morning glory family, is advertising its location. It's a non-native vine that is too aggressive. While I went around pulling it out (if we could use herbicide, we could kill its roots and be freed of an ongoing task), I checked to see what other plants are rebounding. 

Joe Pye Weed is back, as is fringed sedge.

Good to see boneset and Hibiscus popping up. They don't look like much now, but a (wild) gardener can see the promise in these little nubbins.

It can be a challenge to distinguish a blackhaw viburnum sprout from

silky dogwood. Both of these, along with elderberries, will grow back from their roots to become big shrubs. Since trees become oversized for the site, these shrubs will have to do as places for birds to land and hide. Large shrubs will also help curb the expansionist tendencies of cattails. 

We'll see how the lack of shade, now that trees have been removed, will affect the balance of the various species. Some plants like cattails and lizard's tail may spread more aggressively now that they are in full sun. But overall, the rebound is looking good.

Documenting the PHS Ecolab's Recovery From Last Year's Trauma

Passerby on Walnut Street may have noticed that the Princeton High School Ecolab wetland was completely stripped of vegetation by an outside contractor this past November. After the shock of having so many native shrubs and wildflowers suddenly gone, it took us awhile to realize that the roots of the native plants might still be alive beneath the bare dirt. Having lobbied successfully to have stewardship of the Ecolab returned to the teachers, students, and volunteers who had cared for it free of charge for fifteen years, we are watching for signs of its rebirth. 

Most obvious is the annual grass planted by the contractor for erosion control. But I took a closer look and found gratifying evidence that the wetland will rebound. Click on "Read more" below to see a photo inventory of 40 native species (and a few very manageable weeds) that have popped up thus far, ready to refoliate this wonderful teaching resource for the school's environmental science program.

Where Have All the Pollinators Gone? -- Summer, 2021

Wherein is discussed the season's paucity of pollinators, the curiously prolific presence of hornets, and possible causes thereof. 

With the coming and the going of this year's autumnal equinox, it's time to look back on a long summer and ask, "What happened?" Or, more precisely, "What happened to the happening that didn't happen?" 

There's lots of talk about how insects are in decline and that we need to plant more wildflowers to support them. A local ecologist and avid birder, David Wilcove, co-wrote an oped in the Washington Post about the danger posed by insect decline, and the need to better monitor populations, as is done with birds.

In past years, a summer's climactic buzzfest on the boneset

This year, there was a steep decline in pollinator numbers in Princeton. Each year I grow a banquet of wildflowers in my backyard for all manner of insects to feast upon. In past years, they'd come from near and far, their numbers building through summer, climaxing in late August in a buzzfest on the boneset. Though mountain mint is another great draw for insects, in my yard it was boneset in particular, clustered here and there in the garden, that in past years drew the multitudinous shapes and sizes of the insect world. Its broad disks of tiny white flowers seemed like a Serengeti in miniature, an open plain perched conveniently four feet above the ground, teaming with life. It was a chance to see the insects close up, they being so focused on the nectar or each other that they took little notice of me.

Then, two years ago, and again last year, the numbers of insects were down--still numerous but not enough to stir that late-summer's jazzy feeling of frenzied activity. 

2021: An astonishing diminishment

And this year? This year, boosted by the rains, the wildflowers grew to fabulous size. Broad arrays of blooms mounted on multiple stems stood at the ready. In early summer, while periodical cicadas held center stage, the numbers and variety of pollinators were building nicely. 

But then, as the wildflower meadow's heavy hitters--the cutleaf coneflowers, Joe-Pye-Weeds, bonesets and wild sennas--unveiled their fabulous blooms for the mid-summer festival of nectar, the insects were no-shows. Abundant flowers had few pollinators, and sometimes none at all. Diversity dwindled to some tiny somethings, a few bumblebees and even fewer honey bees. 

Sifting through possible causes for the decline

Possible causes for the dramatic decline have been offered: extreme heat, more homeowners fogging their yards for mosquitoes, expanding monocultures of lawn and invasive species. Or perhaps the climate-changed winters have messed with insect dormancy.

The rains of July, the rains of August

What I have particularly noticed over the past three years, however, is the increase in rain during the summer. Rutgers precipitation data for NJ show increased precipitation particularly over the past two years in July and August. Not only has there been more rain, but the intensity of the rain has increased. The sound on the roof is different--one can hear and even feel the extraordinary density and weight of the rain. The deep trauma of Hurricane Ida was the climax among multiple intense storms before and after. The ground and foliage are literally getting beaten up by these deluges. Insects try to hide during storms. Some live in the ground. The harder the rain, the fewer places to hide, and the more likelihood that a ground nest will be flooded out. All that sustained moisture could increase the risk of disease, which an entomologist friend says can play a big role in bee numbers. 

Some of us noticed other changes as well. Gladly, the numbers of odorous house ants invading our kitchen were down from previous years. Mosquitoes in our area seemed relatively rare in early summer, though numbers surged later in the season--tiny ones, probably asian tiger mosquitoes. 

A proliferation of hornets

What was most striking and very strange was a proliferation of hornets. Last year, I seldom saw them, but oftentimes this summer, approaching a patch of flowers, the first thing that would catch my eye was not pollinators but the hornets that can prey upon them. 

We have two kinds of insects called hornets. One is the European hornet, which looks to me like a stocky bee--black markings with a particularly thick yellow abdomen.

The other is the bald-faced hornet, a native insect with black markings and a whitish face. 

Both are hard to photograph because they don't land, but instead keep cruising around the flowers. Periodically they may bump into a bee that was minding its own business on a flower. The contact lasts a split second, then the hornet flies on. The purpose of this brief harassment is not clear. 

Here's a bald-faced hornet in adult and larval form, found on a fragrant of nest someone left at the curb. Both kinds of hornets live in nests that are in or hang from trees. The paper they make, by the way, is beautiful when looked at close up.

Why the proliferation of hornets, cruising relentlessly among the flowers with a sense of urgency but no clear goal? Maybe they just seemed more numerous due to the lack of other insects to catch one's attention. Or maybe the fact that they live in elevated, waterproof nests allowed them to better survive the intense storms. 

The seeds of change planted over centuries

In any case, this summer was not the lively pollinator party I was used to playing host to, both in my backyard and at our Botanical Art Garden (the "Barden") in Herrontown Woods. One interpretation is that the carbon dioxide we've been scattering to the winds is now coming home to roost, in the form of weird winters and intensified storms. In Princeton, basements flooded that had never flooded before. It's not a stretch to hypothesize that many bees also find themselves newly vulnerable to the merciless power of the rain. And then, on the sunny days when pollinators can make it to the flowers, there's the haunting background of patrolling hornets.

In a docile wasp, some small comfort

As students returned to the university, I remembered helping my daughter move in to Whitman College two years ago. In the courtyard, I had noticed thousands of wasps cruising just above the grass. It was a mating dance, of no danger to the parents and students passing by, of blue-winged wasps. I had recognized their distinctive orange abdomen from those that would frequent the flowers in my backyard, a mile away from campus. 

This year, I had seen only one in my yard, and wondered whether their improbable annual ritual was still playing out at Whitman College. 

What I found on Sept 2nd were perhaps a hundred wasps flying in their usual criss-cross manner a foot above the lawn. Some seemed fatigued by it all, and would abandon their flight to sit among the grass blades for awhile. Though their numbers were down from the thousands I'd seen two years prior, I was glad to see any at all. And a student sitting in a lawn chair, scrutinizing his computer, told me there had been many more ten days prior when students first began moving in. 

It would be nice to think that the paucity of pollinators I observed this summer was an isolated affair. But others around New Jersey have made similar reports. An entomologist friend who lives in Oregon told me that he's seen "a very significant decline in pollinators" this year, probably due to drought, though he also said that each species can vary in numbers year to year. 

An ark is built of something more than flowers

We take so much for granted in our lives. When something breaks, that's when one has to study up and figure out how it works, what went wrong, and how possibly to fix it. The insect world has been taken for granted since forever. Annual bird surveys benefit from a community of avid birders, but citizen scientists who are up to speed on the mind-boggling diversity of insects are fewer to come by. We thought we could just plant some flowers and the insects would come, but the needs appear to be far deeper than that. 

Monarchs and a Mid-Summer Multitude of Wildflowers at the Barden

So, I was at the Barden today, that being the Botanical Art Garden in Herrontown Woods, and amidst all the positive energy of budding flowers I had a cynical thought. There are a couple spots around the Veblen Circle of wildflowers where milkweed has been spreading. Lots of leaves and none of them being eaten by monarch caterpillars--an all too common observation over the years. People say to plant milkweed to help the monarchs, but the monarchs aren't helping themselves to the milkweed. What gives? 

As if on cue, a monarch appeared an instant after I had that thought. Only the third I'd seen this summer, it was checking out the milkweed and other plants growing in the sunny openings of the Barden. There are many kinds of native flowers blooming right now, which I'll show photos of later in this post, but the monarch headed over to one in particular,

a buttonbush, whose tiny flowers form the shape of a golfball--a convenient surface upon which the pollinator can go from flower to flower, sipping nectar. For an insect it must be like an assemblage of Hold the Cone miniature ice cream cones, but no need for a freezer. 

Moments later, another monarch butterfly caught my eye, and this one was showing a more intense interest in the milkweeds. There are two types at the Barden--purple and common. Both kinds spread underground, creating clones with many stems--enough to support a whole gang of hungry caterpillars. The butterfly was landing on the edge of the purple milkweed leaves and dipping its abdomen under the leaf to lay an egg. 

After doing this a number of times, it headed elsewhere, allowing me to take a look. Not easy to see. There, in the lower left. 

Here's an egg a little closer up.

There's actually quite a bit going on underneath a milkweed leaf. Here was a whole cluster, which I'm guessing are the eggs of the milkweed tussock moth--another Lepidoptera that can stomach milkweed's cardiac glycosides. 

Of course, it's a hopeful sign to see a monarch laying those single eggs, but we saw this last year, and it didn't lead to any sightings of caterpillars later on. It's possible the eggs are getting eaten by ants and spiders. A complex food web can have its perils, and it's interesting to note that milkweed that once grew in farm fields (in the days before Roundup-Ready corn and soybeans) might have had better monarch survival due to there being less predators in that simplified landscape. 

Still, we can hope that this is the year when the Barden does its part to build monarch numbers in preparation for their perilous flight back to Mexico in the fall.

Another sweet sight today, again not captured in a photo, was the pair of hummingbirds that landed on a wire cage just five feet away. Hummingbirds, in my experience, actually spend a lot of time perching, which makes sense given how intense is their flight. Their presence was the answer to a question overheard at the checkout counter at the Whole Earth Center: "Has anyone seen any hummingbirds?" Like monarchs, they also have to negotiate a difficult migration every year.

Maybe they were attracted to the tubular flowers of wild bergamot, 

or beebalm, or jewelweed.

What follows here is a documentation of all the flowers seen blooming right now in the Barden, as the midsummer diversity kicks in. After all the work of weeding and planting, there's pleasure in simply walking the paths and appreciating all that is growing so enthusiastically. 

There's a lot to document. These signs, created by Inge Regan, offer four species to look for. When learning plants, it's good to focus on a few at a time. 

For those more familiar, we've brought together some 40 species that bloom in mid-summer, some of them shown below. Maybe you can walk the pathways and see how many you can find. We're trying to figure out how to pot up all the excess and make them available to visitors to take home.

To see some of the other species showing their stuff this time of year, click on "read more", below.