Saturday, July 20, 2024

How Are Monarchs Doing in 2024?

Several times a year, the question of "How are the monarchs doing?" rises in my mind. An internet search typically ends up at Chip Taylor's blog on Monarch Watch. There you will find thoughtful commentary and deep analyses, a mixture of good news and bad news, as this extraordinarily resilient species faces ever greater challenges. In 2024, overwintering numbers in Mexico were the second lowest ever recorded, with 2013 having been the lowest. Chip's more recent posts tell of a rebound this summer, as this robust and prolific species has increased its numbers during its migration, following the growth of milkweed north in a tagteam of successional generations, spreading into all corners of the eastern U.S.. 

I've had maybe five sightings of monarch butterflies this summer--a typical number. One appeared frantic, as if it had been searching the great outdoors in vain for a partner. Another was laying eggs on a patch of common milkweed at Mercer Meadows--a beautiful and hopeful sight. Another was in my front yard on busy Harrison Street in Princeton, gathering nectar on a swamp milkweed. 

A few days ago, one was nectaring on a patch of narrow-leaved mountain mint near Herrontown Woods. I was treated to a surprising display of butterfly aggression, as several skippers suddenly ganged up to chase the monarch away from the mountain mint. 

Part of that competitive fervor may have to do with the scarcity of pollinator plants. In a 4.5 acre field, there were only two small patches of mountain mint. Since forests don't supply summer nectar, meadows like this are where monarchs and other pollinators are going to find food and each other. Many meadows and roadsides are being taken over by mugwort, Chinese bushclover, and other invasive species with limited utility for pollinators. Add that threat to all the others: habitat loss, climate change, indiscriminate herbicide use along roadsides. This meadow is preserved, but that's really just the first step in realizing the meadow's potential as habitat that can help sustain species like our beloved Danaus plexippus, aka monarch butterfly.

Wednesday, July 17, 2024

The Wineberry Tease

Wineberry (Rubus phoenicolasius) is a non-native bramble common along woodland edges. 

Because its berries are tasty, I have in the past hesitated to remove it from our various wild garden areas. But this year, the hesitation is fading fast. One reason wineberry is getting cut down and pulled out is the cumulative impact of thorns on my sympathies. Repeated prickling sensations from running up against a wineberry or even a native blackberry gets old.

Another reason is that the dreamed of harvest of delicious wineberries is very nearly all intercepted by the birds, particularly catbirds. The early bird gets the wineberry. leaving us a disappointing display of "too late" and "too soon."


Another good reason to remove wineberry is that it will take over your garden. Here's a wall of wineberry along a road in Kingston, more than holding its own amidst other invasives like mugwort and multiflora rose. 
Even wineberry will lose out to the mobbing behavior of the uber invasive porcelainberry vine. You can see wineberry's last gasp at the bottom of the photo. 


Friday, July 12, 2024

A Followup on Beech and other Threatened Native Trees

Having grown despondent about the devastating toll beech leaf disease will likely take on Princeton's beech trees, I was surprised and somewhat heartened by what I found on the Princeton University campus. 

A friend from childhood was visiting me for the first time, and as I showed him and his wife around campus, I began to feel as if we had somehow been transported back to an era before introduced pathogens and insects had marginalized many of our native trees.

An American white ash towered over us, healthy as can be. American elms, too, grew as if Dutch elm disease had never arrived.

Unlike the ailing beech trees up along the Princeton ridge, the beeches on campus appeared unfazed by beech leaf disease.

I looked for signs that these trees had been injected with chemicals to ward off invasion, but found none. Surely, though, this improbable survival depends heavily on medicinal intervention.

Since I first alerting the community to the presence of beech leaf disease in Princeton in a blog post and letter to the editor, some articles have been written in the local press--one in TapInto Princeton and one in Town Topics

Both mention phosphites as the primary treatment available thus far. Applied to the soil, phosphites are a biostimulant that improves the tree's immune system response. I was skeptical that this could make much of a difference, but the University appears to be having good results. Grounds supervisor EJ May said they started seeing signs of beech leaf disease two years ago. Speaking generally about efforts to save native trees, he acknowledged some losses but some success as well.  


Another lead I had checked out was a kind of beech mentioned in a list of special campus trees.  Called a fern-leaved beech (Fagus sylvatica 'Asplenifolia')--a variety of European beech with unusual foliage--the university had gone to great lengths to save this extraordinary specimen during construction of the new chemistry building. The tree's described online as having "no serious insect or disease problems." Was the text written before beech leaf disease was discovered in 2012, or might this variety have some sort of natural immunity? I stopped by to take a look, and could find no visible symptoms. 

There remains, too, an uncertainty as to the origin of the nematode that causes beech leaf disease. It is most similar to a species found in Japan, but differs in some ways. 

Maintenance Will Determine the Fate of the Betsey Stockton Garden

When I look at a plant, a garden, a meadow, a forest, I can see the future. It's a form of extrapolation, defined in the Oxford Dictionary as "the action of estimating or concluding something by assuming that existing trends will continue." I only realize now, writing this, that not everyone exercises such powers. Not everyone has been a gardener of landscapes for fifty some years, accumulating memories of myriad plant species and observing their behaviors. I've seen thriving raingardens and neglected ones, healthy meadows and forests, and degraded ones. I've observed how various invasive weeds spread and come to dominate, each in its own manner and at its own pace. These are the accumulated data points used to predict the future.

One very satisfying thing about extrapolation is that I can see, in my mind, the flower a bud will become. But with that same power to see a garden blooming while still in bud, I can look at a garden in what for others is glorious bloom and see the "seeds" of ruin--the scattered pockets of invasive mugwort, nutsedge, stiltgrass or lesser celandine, crown vetch or Chinese bushclover that without early intervention will quickly expand and ultimately prevail. 

My interventions--a broad mix of successes and failures--have taught me above all that early intervention can make the difference between hope and despair. 

One special garden in town that I stop by to check up on, like an old friend, is the Betsey Stockton Garden planted atop the Firestone Library at Princeton University. This is a complex native planting, containing 35 native grassland species. The person or crew maintaining the garden needs to be able to recognize and identify all 35 intended species, plus all the weeds that could potentially cause problems, not only when they're blooming but at all stages of development. 

That deep knowledge is a tall order. Knowing how little respect maintenance often gets, I worry about this meadow garden in the longterm. Will it receive the knowledgeable, strategic attention it needs to thrive? This photo of wild bergamot blooming with lots of clumping goldenrods suggests things are going well. 


Here, some black-eyed susans lend color, but the pink blooms of quickly spreading non-native crown vetch spell trouble.
New to me is a weed called rabbits foot clover, which may have hitchhiked in from whatever distant nursery the intended plants came from. This, too, was not caught early, and now poses a significant challenge.

Thankfully, there's only one small patch of the fearsome mugwort, but that could quickly expand if not dealt with quickly. Getting as close to zero tolerance for invasives as possible makes maintenance much easier. 

Maintenance is not given its due in part because success is often invisible. In a house, we note dirt's presence, not its absence. A well-run government agency doesn't make it into the news. The bass player who provides the harmonic foundation for a band often goes unnoticed until he plays a wrong note. In medicine, catching problems early doesn't pay as well as dramatically rescuing someone whose problem has grown into an emergency. Extrapolation can help with this. It allows us to see large consequence in small acts, to appreciate how big a problem has been avoided by digging up a small, isolated patch of mugwort.

I found a few relevant local writings. One was an opinion piece in the Daily Princetonian by an undergrad, calling for more native plantings on campus. Planting is a good start, but what goes unmentioned in the opinion piece is that maintenance determines any planting's fate. 

One strategy being used in newer native plantings on campus is to plant gardens with only three or four species, with lots of mulch inbetween plants. This reduces the amount of training required for maintenance. 

Other local writing specifically about the Betsey Stockton Garden can be found in the Princeton Magazine. It includes the list of intended plants (below), and describes the garden as low-maintenance, but that assumes the invasive weeds will be caught early and removed before they can spread.

The Betsey Stockton Garden was planted in 2018, two years after the demise of another campus native planting, around the Neuroscience Institute. Hopefully some lessons are being learned, and the University will bring the necessary expertise and strategic timing for maintenance to bear on this lovely, botanically complex planting. 

Native Plants Featured in the Betsey Stockton Garden
(Some are used on the High Line as well.)

Grasses:
Carex comosa, Appalachian Sedge
Carex pensylvanica, Pennsylvania Sedge
Festuca ovina, Sheep’s Fescue
Festuca rubra, Creeping Red Fescue
Sporobolus heterolepis, Prarie Dropseed
Elymus virginicus, Virginia Wild Rye
Schizachyrium scoparium,
Little Bluestem
Tridens flavus, Purple Top

Shade Plants:
Aqueligia canadensis, Wild Columbine
Aster laevis, Smooth Blue Aster
Blephilia ciliata, Downy Wood Mint
Erigeron puchellus, Robin’s Plantain
Eurybia divaricata, White Wood Aster
Polemonium reptans, Jacob’s Ladder
Sisyrinchium angustifolium, Narrow Leafed Blue-Eyed Grass
Solidago caesia, Blue-stem Goldenrod
Solidago flexicaulis, Zig-Zag Goldenrod

Full-Sun Plants:
Asclepias tuberosa, Butterfly Milkweed
Aster laevis, Smooth Blue Aster
Aster pilosus, Heath Aster
Baptisia alba, White Wild Indigo
Baptisia perfoliata, Catbells
Centaurea cyanus, Cornflower
Chamacaesta fasciculata, Partridge Pea
Coreopsis lancelota, Lanceleaf CoreopsisEchinacea pallida, Pale Purple Coneflower
Echinacea purpurea, Purple Coneflower
Monarda fistulosa, Wild Bergamot
Penstemon digitalis, Beard Tongue
Rudbeckia hirta, Blackeyed Susan
Solidago juncea, Early Goldenrod

Thursday, July 04, 2024

Mixing Real and Unreal in a Hidden Garden on Vandeventer Avenue


Along Vandeventer Avenue, hidden behind a hedge and shaded by this most glorious of all river birches, lies a little garden that combines the real and the unreal in delightful ways. 
What looks like a congregation of daylilies is actually a mix. The bloom in the foreground is real, while those in the background are silk flowers bought at the Dollar Store. 
Nearby, a real daylily mixes it up with faux irises. 

I mean, why not? We are so quick to take flowers for granted. This at least makes us stop and look more closely. Why not play with the art of imitation, which has reached such a high level, be it in silk flowers or the animated movies that move us as much as those with real people. 

Jim Firestone, who with his wife Tina tends this garden, says the approach has parallels with Seward Johnson's sculptures at Grounds for Sculpture. It's the art of the double take. 

I once wrote a comic script called "Spring Training," in which Nature has tired of the same old progression of blooms in the spring and decides to go rogue, mixing peonies with crocuses, tulips with Rhododendrons. Her exasperated coach tries in vain to convince her to stick with the status quo.
Outside the hedge, seen but not really seen by passersby heading down from Nassau Street, a morning glory rises improbably out of the concrete every year. It looks like it's blooming, but ...

surprise! Real blooms will come from the real morning glory later in the season, but in the meantime, why not have some fun?