Monday, May 25, 2020

Some May Wildflowers

A random assembly of May wildflowers, some seen here, some there.

Fringe tree is more like a shrub, but sometimes achieves the size of a small dogwood. Give it some sun and it will fill its form with lacy white in May. Native to the southeast U.S., I've seen it growing in the wild only once, in a preserve we created in Durham, NC. Some internet postings say it can be attacked by the emerald ash borer, but we have two that are flourishing thus far.

This black cherry was blooming conveniently next to a friend's front porch. Black cherries have "black potato chip" bark and little black cherries preferred more by birds than humans. They are common in backyards and in the wild, thriving on edges or in younger forests, before getting shaded out by larger trees.

Two other flowering trees easy to spot along roadsides this time of year are black locust, with its masses of white flowers, and princess tree (Paulownia tomentosa), an asian species with tubular purple flowers.

Another friend who was donating a tree to us happened to have a Leucothoe in his backyard. A good specimen like this can be attractive. There are native species--one that goes by the name "doghobble"--but I can't say I've ever actually seen them growing in the wild.

Big-leafed magnolia--relative of the very common tulip tree--is one of many seldom seen native magnolias. There are some growing in an area of the Institute Woods in Princeton, but I had also seen one growing in Herrontown Woods a few years ago, some distance off one of the trails, downslope from the ridge. Not remembering where it was exactly, I wondered if I'd ever encounter it again. Then one day recently my friend Kurt was showing me some trail work that he and his wife Sally were doing. Our conversation, which began shifting from trails into philosophy and history, took me out of my usual way of moving through that particular section of trail, and when I looked up I saw in the distance the big-leafed magnolia, twice the size it was before and in full bloom.

Each flower is like a candle centered on a platter of leaves.

Surprised to see cuckoo flower still blooming,

and rue anemone, too, is having a long season in this cool spring weather.

Mayflower can cover the ground in leaves but few flowers, as is the habit with trout lily earlier in the spring.

Each leaf of Jack-in-the-Pulpit has three leaflets. Males have one leaf, while the females, arising from a more robust root with enough stored energy to support production of seeds, has two. Each individual plant can change sex, year to year.

Jack-in-the-Pulpits are fairly common, in part because deer often leave them alone. If they do browse the leaves, it's more often of the females, whose leaves may be more nutritious.

Golden ragwort in the field next to Veblen House,

growing in what looks like a field of grass, but in this small patch there is no grass but instead something unidentified, more like a sedge or rush.

Wild geranium adds some color along trails.

Fairly rare is the wild comfrey, with a few small flowers lifted above a rosette of big velvety leaves, growing only on the special soils of the ridge.

This cool, wet spring is showing the showy orchid to be more widespread along the ridge than I had previously thought.

A bellwort with its yellow flower hanging like a bell.

A bit of a celebration here. These are the first blooms of a native azalea relocated to a sunny area of our botanical garden next to the parking lot at Herrontown Woods. This species, once common along the ridge, has long been prevented from blooming in the wild due to deer browsing and deep shade.

Tuesday, May 19, 2020

Primrose Past and Present

This post was supposed to be about the mystery flower in the photo, sent to me May 10, but its shape brought back memories of primrose past and shifted the writing to something more like memoire. Sometimes, sitting down with the intention of writing about one thing, something very much different pops out.

You can skip to the chase by scrolling down to the identification of this primrose found by Susan Michniewski during a walk in Woodfield Reservation, but first a primula-induced interlude that skips back to the 1970s.

When I was 16, my father left Yerkes Observatory to become chair of the astronomy department at the University of Michigan. For my family, that meant moving from small town Wisconsin to Ann Arbor, MI. It wasn't much of a move compared to the overall size of the universe, but for me it meant transitioning from a school with 50 kids per grade to one ten times larger. I don't recommend moving in the middle of high school, but at the time I was so introverted that one place was probably about as good as another. In retrospect, having made as yet no sense out of humanity or myself, I was well primed for connecting to the plant world.

During the house search that first year in Ann Arbor, we got lucky. My father had learned through the department that a deceased physicist had left behind his estate--a house and garden. It hadn't even gone on the market, and I remember our first magical visit to the empty house in the fall. The abandoned feel of the place stirred parts of my brain that must date back to a distant, less populated era, as when a wandering tribe might happen upon a long abandoned valley that nature had begun to reclaim, and feel a sense of forsaken treasure and possibilities.

A door to the back patio had been left open at one point, because autumn leaves lay scattered on the hardwood floor of the living room lined with metal casement windows and paneling made of sweetgum wood. The living room had a high ceiling, and we were told that it had been designed for music. The physicist, Walter Colby, I have recently learned via the internet, once dreamed of being a classical pianist. A few of his effects had been left behind--a brass inkwell, and green paper napkins that referred to the miniature valley behind the house as "Thorn Hollow." The house was embraced by a lovely english garden, and that first spring, the garden revealed its secrets--a salve for my lonely soul. Down in the hollow a venerable elm tree spread its graceful limbs over walkways lined with yellow primrose and Pulmonaria. Sweeps of Scilla and other bulbs ornamented the slopes. Native wildflowers--mayapples, Trillium, Solomon's seal--rose in the informal beds defined by the trails. A quince tree below the rock-walled terrace still bore fruit.

It seemed a timeless place, with balance and beauty, a peaceful coexistence of plant life, but over time that timelessness was put to the test. The elm tree succumbed to Dutch elm disease. The redbud became overgrown, losing its graceful shape. Maintaining balance in the garden beds involved many hours fighting the advances of garlic mustard and the goutweed that clung to the ground with a vengeance. In sunnier areas, pretty garden phlox began to pretty much take over. Myrtle proved a mixed blessing, too, embedding itself most everywhere.

The more I got interested in gardening, the more I found myself spending an inordinate amount of time dealing with a few bad actors that refused to play well with others. There were still joys, like when a pawpaw tree volunteered in one of the beds and ultimately bore fruit, its origins a mystery. Favoring practical plants, I started a vegetable garden. As trees closed the canopy, we moved the vegetables out front to the sunniest place remaining, between the sidewalk and the curb. Neighbors, at least the neighbors who commented, took delight in our unorthodox rethinking of the front yard.

The primrose in that garden were yellow--probably cowslip (Primula veris), native to Europe--and were about as docile and unadventurous as can be, not weedy in the least.

That's why I was surprised to hear that a primrose species was found this spring growing wild in Woodfield Reservation. It had the same rosette of leaves at the base as cowslip, with a burst of flowers like a circle of trumpets at the top of the stem. But the flowers were red or white rather than yellow, and this one was reportedly spreading along the streambank.

We decided it is Primula japonica. I checked in with Mike van Clef of the NJ Invasive Species Strike Team, who said he hadn't encountered it anywhere in NJ other than near the footbridge in Woodfield Reservation, and that it's worth keeping in mind if it seems like it's spreading.

Thanks to Susan Michniewski for sending photos, and to photographer Douglas Meckel.

Thursday, May 07, 2020

Murder Hornets and Princeton's Cicada Killer

The scary reports about murder hornets offer an opportunity to write about invasive species and insects generally. "Murder hornet" is a nickname, but the insect's real name, Asian giant hornet, is not very reassuring. There have been some scary videos making the rounds. The NY Times article was less sensationalistic, and captured well the potential threat along with the actions being taken to counter it. Rutgers hastened to clarify that the insect isn't found in the northeastern U.S.. And it's still not clear whether the AGH (Asian giant hornet) has established a population in the northwest, and if so whether the population is still small enough to be eradicated.

Big insects are scary. One nightmare remembered from childhood was of an ant about two feet long. I had a memorable bike ride home one day with a wasp having perched on my shoulder. I decided to just let it sit there, and eventually it flew off. The more I learn, though, the less scary most insects become. Late last summer, I waded out into a lawn full of blue-winged wasps flying about, knowing they were harmless. Knowledge can lead to a gentle response to something seemingly dangerous in nature. When the fishhook-shaped thorn of a multiflora rose bush pricks the skin, the best thing to do is relax, move towards the shrub rather than away, calmly cut the stem to which the thorn is attached, or rotate so the thorn has a chance to slip back out of your clothing.

Learning more about the Asian giant hornet can bring at least a little reassurance. Along with the uncertainty of its establishment in the U.S., I heard via an invasives listserve that "AGH does not attack people unless it feels threatened", and though they do pose a threat to honey bees, they only "attack and kill other bees in the late summer when developing males and future queens need extra protein to complete their life cycle."

The largest wasp in the Princeton area is the cicada killer, which looks much scarier than it actually is. Like dragonflies, they can tackle insects in midair. Ten years ago, there was a colony of cicada killers living near the Princeton Community Pool. Cicada killers are large wasps in Princeton that dive-bomb cicadas in mid-flight, then haul them back to their underground nests to use as food for their young. They pose little danger, but the colony was exterminated by the parks department because the wasps alarmed people walking by in their bathing suits. (Photo is a dramatization featuring our local cicada killer and an unknown actor.)

While pointing out that some threatening looking insects can be benign, I've also long advocated for action on invasive species. As introduced plants like lesser celandine and porcelainberry spread their smothering growth across Princeton's open space and lawns, there is an opportunity to keep them out of some areas through proactive action. It's been very hard to get people to think strategically, however.

The Asian giant hornet is at least being taken seriously. Quick action could prevent it from getting established in the northwestern U.S., though usually an introduced species is already established by the time anyone sees it in the wild.

As with COVID-19, there are questions as to how the hornet would adapt to climate in the U.S. The L.A. Times questioned whether the AGH would adapt to California's cool summers and warm winters.

Some introduced insects become enduring pests, like Asian tiger mosquitoes that bite annoyingly during the daytime, and the Emerald ash borer that has decimated ash trees. On the other hand, we hear little about the killer bees that were touted as such a big threat in the 1980s. The best news would be that the Asian giant hornet hasn't become established after all.