Wildflowers and People Gather By the River

What a glorious day, this past Sunday, down along the canal in Princeton. Cool, sunny weather drew people to the canal, by boat, foot and bicycle. The sounds of laughter and conversation mixed with birdsong and a generous show of summer floodplain wildflowers.

Boys returned to their Huck Finn roots,

and insects, too, gathered by the river

or bathed in the sun.

Many different species of oak have long gathered along the section of the towpath between Harrison St and Washington Rd, planted back when the university viewed the canal as an ornamental entryway to campus.

Here's white oak, with it's rounded lobes,

and possibly a post oak, with its lobes arranged in the shape of a cross.

Swamp white oak and bur oak have similar leaves, swollen towards the tips, like the bison that used to forage in the oak savannas of the midwest and south, back when mildfire could play through and refresh the landscape.

Not sure what type of oak this is.

It was a day when nature seemed to be moving towards restoring balance. The overly aggressive multiflora rose was getting a humbling dose of rose rosette disease.

One Ailanthus, at least, was being slowed down by the munchings of the caterpillars of the Ailanthus webworm moth.

The adult is the orange patterned insect in this photo.

And a honeysuckle shrub was being hampered by some sort of witch's broom growth.

Queen Anne's Lace was being pretty without taking over.

Introduced knapweeds like spotted knapweed have spread very agressively in the midwest. I've been trying to believe that this Tyrol knapweed will be relatively benign as it spreads slowly along the canal. Here, at least, it's hosting a monarch.

True, the porcelainberry was having its way in one of the openings in the canopy,

and capitalizing on a tree's demise.

Stiltgrass still lines the nature path,

and a Norway maple's dense shade was stunting growth beneath it.

Mugwort framed concrete marker, but hasn't dominated along the canal like it sometimes does in gas line right of ways.

Signs at the Harrison Street crossing warned of hydrilla, an aquatic invasive plant. None of this, however, could break the upbeat mood of a cool, sunny Sunday in late July.

Flowers from earlier in the year were quickly turning into seeds, like buttonbush

silky dogwood,

common milkweed,

One of the ornamental cherries planted by the university long ago,

pokeweed,

and tall meadow rue.

Seeing native shrubs like this elderberry trying to grow along the banks of the canal, I long ago envisioned managing the banks for native shrubs that could beautify and provide abundant wildlife food. But the banks of the canal are managed independently of the towpaths, by a different agency. As with most landscape maintenance, the workers tend to be unselective in what they cut. To preserve the view from the towpath, the bank is cut every few years--not enough time for a shrub to do much flowering and fruiting that would benefit wildlife.

Not far down the lake from Washington Rd. bridge stands the stump of a sweetgum tree once darkened each day by roosting cormorants.

Its life may have been cut short by the excess guano, or its own precarious perch on the edge of the bank. Not sure where the cormorants have gone.

Another sweetgum, with its star-shaped leaves and protruding wings on the branches, was thriving elsewhere along the trail.

Some of the wildflowers have grown to giant size with the well-spaced rains this summer. These cutleaf coneflowers are ten feet high,

as are some of the ironweeds.

The cutleaf coneflowers were the first native wildflowers I spotted ten years ago along this section of the canal, which in turn led to the state park staff reducing the mowing to once a year so these wildflowers would have a change to mature and bloom

Hollow-stemmed Joe-Pye-Weed has really prospered in the open shade of the oaks. Each year there are more patches of these attractive flowers.

Goldenrods can be distinguished by the different shapes of their flowerheads. Some have elm shaped inflorescence,

others are flatter.

Each year, the rose mallow hibiscus bloom along the shore, with lizard's tail and yellow pond lillies extending out into the Carnegie Lake waters beyond them.

It would have been a perfect day to lead what usually is an annual nature walk along the towpath. For 2017, this account will have to do.

Coneflower Attracts Monarch and Much More

Typically, my random butterfly sightings don't go much beyond a tiger swallowtail fluttering in the distance. But on July 19, the purple coneflowers in the frontyard raingarden drew a diverse crowd, including this beautiful monarch. This sighting added to a few sightings elsewhere to suggest that monarchs are rebounding from a couple very tough years in which the overwintering area they occupied in the mountains of Mexico dropped to only a few acres. The blog at monarchwatch.org confirms that they are having a comparatively good year. The magnificent monarch with its matchless migration will always be vulnerable, particularly given the destabilizing effects of climate change, the loss of milkweed in farm fields now that Roundup-Ready corn and soybeans allow elimination of weeds, and the ongoing threats to the evergreen forests the monarchs congregate in every winter. There's a lot more work to do to make their population more resilient, but it's heartening to see them on the upswing.

A black tiger swallowtail in particularly good condition.

This looks to be a variegated fritillary,

with a different pattern on the underside.

A skipper,

a bumblebee, of which there are many species.

It was an oak in the backyard that attracted this moth, possibly a tulip tree beauty moth.

A few days later, we were back to the tiger swallowtail.

Hi Time For Hibiscus

Well, hello there, beautiful. The Hibiscus that's native around here, Hibiscus moscheutos, or rose mallow, is as tough as it is beautiful, thriving along the edges of Carnegie Lake and lining the wetlands of the upper Millstone River, up West Windsor way. Gather seeds from the convenient packaging of its capsules in the fall, and you might end up with some in a wet, sunny spot in the backyard, which is how I know that kayaking up the Millstone River from Carnegie Lake might be particularly lovely right about now.

As part of the Detention Basin Enhancement Program, which did not officially exist until the words were typed a few seconds ago, I took some of its copious seedlings from my backyard and pressed them into the ground at Smoyer Park yesterday evening, as the thunderstorm approached. Combining the planting with weeding, I pulled up a horseweed or pilewort, pressed the Hibiscus root into the resulting hole, then lay the pulled weed gently over top of the Hibiscus, to shade it while its roots take hold. Improvised, but potentially effective.

Other members of the Hibiscus genus get into the act this time of year. Rose of Sharon (Hibiscus syriacus) can stand alone as a large shrub, or grow vertically enough to be a hedge. Not native, it tends to spread by seed in the yard, but hasn't made the leap to wilder areas that I know of.

There were big-flowered Hibiscus in my sister's garden in Cleveland that looked like this. It's a cultivar, and I resist calling it the same species as the local Rose Mallow, but am finding no other scientific name on the web.

Other dramatic native Hibiscus, not seen growing naturally around here, are H. coccineus (Texas Star Hibiscus) and H. laevis.



Update: A week or so later, Flower of an Hour (Hibiscus trionum), an Old World weed, showed up along our curb. Went back maybe an hour later, and the flower had already closed.

Bamboo at Princeton Battlefield Gets its Summer Cut

This past Saturday, four of us gathered for a well-timed intervention at the Princeton Battlefield. The Friends of Princeton Battlefield had cut down a patch of bamboo in the spring, but the roots had quickly sent up a new crop of shoots--essentially foliar solar panels that would quickly begin resupplying the bamboo's powerful root system. By following up and cutting the new shoots, we deprived the roots of any return on their investment in new infrastructure. This is the third year we've done this, and each year the job gets easier. A massive stand of bamboo has been reduced to modest sprouts easily managed.

Thanks to volunteers Jill Warrington, Andrew Thornton, and the leader of the Friends of Princeton Battlefield, Kip Cherry. My participation was a bit of outreach from the Friends of Herrontown Woods, on the other side of town.

The Incredible Whiteness of Early Summer Flowers

Count the ways a flower can be white in early summer:

A white version of obedient plant in a frontyard raingarden fed by water from the roof,

The first summer bloom of rose mallow hibiscus in a backyard swale fed by water from the uphill neighbors,

boneset getting ready to pop,

Culver's root,

some elderberry flowers late to the party, growing next to the chicken coop,

pokeweed,

tall meadowrue,

lizard's tail,

bottlebrush buckeye,

black cohosh up among the boulders on the Princeton ridge,

buttonbush and

oakleaved hydrangia, both growing in front of the Whole Earth Center,

Yucca filamentosa in a neighbor's front yard,

and, at Westminster's parking lot raingardens, some unintended white clover,

catnip,

and Queen Anne's lace.

These last three on nonnative; the rest are native to the eastern U.S.