Seeds for the Spreading

Hibiscus seedheads act like baseball mitts, catching snow in this winter-come-lately weather. There's been some seed collecting this past fall and winter for a couple projects of the Friends of Herrontown Woods. At Smoyer Park, we're partnering with the Princeton Rec. Dept. and Partners for Fish and Wildlife to convert a detention basin to a native wet meadow.

And at the Veblen House, Kurt Tazelaar has been restoring an area where Elizabeth Veblen likely had her daffodil nursery. Over the intervening fifty years, wisteria had spread from the house to climb the trees, obscure the fenceline and claim the sunlight in this woodland opening.

Both of these spots have a combination of wet ground and sun favorable for some favorite native wildflowers that could bring some color to the neighborhood in late summer.

Many of the seeds come from my backyard, which has become a contained riot of local genotypes of cutleaf coneflower,

wild senna,

ironweed, and many others. Leaving last year's stalks up until spring provides cover for our free-ranging chickens, food for the birds, and a superstructure for overwintering insects.

Here's a Eupatorium, with a name only a botanist could love--late-flowering thoroughwort--

and the clustered seeds of buttonbush.

Ironweed seeds have some beauty to them, leaning out over the DR Canal, which was the original source for most of these floodplain species that I've been spreading across Princeton over many years. The canal's sunny openings and lack of past farming provided a place these species could live to bloom another day.

One doesn't need to be near a stream to have floodplain habitat, as many yards around town have low ground that remains wet for long periods, and downspouts create miniature floods of water that can be made to linger in a raingarden. The more places these wildflowers grow in town, the more resilient is the overall population, not only of various wildflowers but also the pollinators that depend on them for food in late summer, when woodlands offer little nectar. Think of it as repopulating the local food desert, ecologically speaking.

Sometimes, seedheads find their way indoors, in this case, Hibiscus and Culver's Root. The Culver's root this seedhead comes from was bought, for lack of a local population.

The slow-release saltshaker-like capsules of Hibiscus moscheutos in early winter, before the seeds have been eaten or shaken out by the wind.

Some hearts a bustin' berries in autumn (Euonymus americanus). A favorite of the deer, only two wild populations of this native shrub have been found in Princeton, both at Herrontown Woods. Because deer find this shrub so delicious, fenced-in backyards become its best chance for reaching maturity.

Stalking the Rare Horsteria Westnut

What kind of tree could this be, so bright and fragrant a week or two ago,

with two kinds of flowers--some white, some lavender? Closer inspection showed it to be a horsteria westnut, that is, a horse chestnut being engulfed by wisteria vines.

If one's going to kill a tree--the likely outcome--this is one of the prettier ways to do it.

August Nature Vignettes

Herein lie a series of mid-summer encounters with nature in Princeton. 

At the Barden in Herrontown Woods, where artistic photos of native plants ring the gazebo, a tiger swallowtail butterfly was caught imitating art imitating nature. Each of the 30 some wire cages harbors a different native wildflower. This one is clustered mountain mint, which is a magnet for pollinators.

Up near Veblen House, sawfly larvae chowing down on a young hazelnut's leaves adopted an S-shaped balletic pose when disturbed. Imagine everyone in a cafeteria standing up and adopting the same yoga position as you entered. With 9 pairs of prolegs, the sawfly larvae are not true caterpillars, which are defined as having only 6 pairs.

The sawflies' choreographed response is similar to that of a real caterpillar called a contracted Datana seen three years ago on lowbush blueberries also growing at Herrontown Woods. 

If you see the top of a lovely young eastern white pine suddenly turn brown, chances are that white pine weevils have paid a visit. The adults overwinter in the leaf litter, then emerge in spring. The females lay eggs in the central stem of the white pine, the larvae then eat the inner bark of the pine, cutting off the flow of nutrients to the terminal stem. 

In late July and early August, the adults emerge via small holes in the bark. The weevils are native, and the pine survives by using one of its lateral shoots to continue upward growth. Evidence of past attacks by weevils can be seen in a pine tree's crooked stem. 

Why is this gangly weed being left to grow in an otherwise groomed suburban lawn? It's a chicory that has worked its way into the heart of the homeowner by fielding an array of attractive flowers through most of the summer. The blooms of the homeowner's frontyard roses and Rose of Sharon shrubs come and go, but the chicory keeps delivering.

The flowers have a delightful shade of blue that lifts the spirit. There's a fun post about a chicory that grew gloriously out of what looked like pure concrete six years ago at a busy intersection, drawing photographers, including me. 

Liking the plant, I'd like to think it "plays well with others", that is, does not become invasive and exclusionary of other plants in the manner of mugwort or Chinese bushclover. But while traveling recently in southern Wisconsin, I did see it thickly established along a lengthy stretch of country road. But a road embankment is an altered soil that often becomes colonized by nonnatives that aren't necessarily invasive in a prairie.

I was impressed to see that this gardener on Valley Road had vanquished the Canada thistle that had pushed up through the mulch earlier in the spring. (See Weeds That Launch an Underground Insurgency.) A garden tells little of the past battles waged to create this gentle scene of coneflowers and black-eyed susans. 

A meadow needs to be weeded like any garden. Sometimes, the process of weeding, by getting us out there, leads to discoveries and a deeper appreciation of the area being weeded. Scott Sillars and I were weeding the meadow next to Veblen House recently, pulling every Chinese bushclover we could find before they could bloom and go to seed, when I discovered a plant not previously known to bloom there. 

Rose Pink (Sabatia angularis) is a biennial in the gentian family. I had been content to call it Meadow Beauty until I took a closer look and realized it has five petals instead of four. 

Another small treasure, found while cutting invasive wisteria vines in a thicket of privet shrubs near Veblen House, was an antler. It's said that shed antlers are rarely encountered because their minerals make for good gnawing by mice and other animals. This one, however, was in good shape long after being shed over the winter. 

When rains are plentiful, sensitive fern can form robust, expansionist stands that make the name seem a misnomer. But the plant lived up, or down, to its name when this summer's drought turned lush green leaves dry and brittle. 

Jewelweed is another example of a native plant that can be robust in wet weather, then get laid low by drought. A couple years ago, there were so scarce in the Barden at Herrontown Woods that we thought of helping them to spread. But the few specimens cast their spring-loaded seeds far and wide, leading to current abundance.

A lot of native wildflowers have "weed" in their common name, despite their positive attributes. Jewelweed is a good example, with its tubular orange flower that attracts hummingbirds, yet its capacity to become prolific can turn it into a weed in our perceptions.

Pokeweed is another native that can overgrow its welcome, looking sometimes elegant, sometimes gangly. More about pokeweed elsewhere on this blog, including its close relative in Argentina that looks like a tree but isn't. 

 

If you like pokeweed but find it gets way too big, you can cut it down in midsummmer, then watch it regrow in a smaller version of itself that might fit the allotted space better. This works with other tall native perennials as well.

Those who leave Princeton in August are missing out on bur season. If you find your leg covered with burs, it could be that you just walked by some stickweed. 

Here's a better photo. It's one of the plants written more about in a post called Deceptive Weeds. 

White avens is another weed that produces burs. 

If you get tired of watching paint dry, you can always drive down Route 206 towards Montgomery and watch Phragmitis reed slowly eat the road. 

You could also watch the condensate drain away from air conditioning units. Water can be pretty exciting to a gardener in the middle of a drought. Air conditioners pull moisture out of the inside air and release it outdoors. The trick is to take advantage of this water and direct it towards plants that desperately need it during hot, dry days when air conditioners are running the most.

One advantage of composting your food scraps in your yard is the surprise plants that sometimes appear among the moldering banana peels and crushed egg shells. This is a volunteer avocado growing in a Wishing the Earth Well composter.  

A friend of mine potted up one of his compost pile avocados and it's now almost too big to get out the door after a winter spent indoors.

There are a lot of native plants that show their beauty in midsummer when many people are out of town. One favorite of mine is woolgrass, which really should be called brown wool sedge, because it's a sedge, not a grass. You can call it Scirpus cyperinus if you want to sound impressive. Most sedges mature in the cool months of spring, but woodgrass develops more slowly, sending up a tall inflorescence that is attractive at all stages on its way to looking wooly.

It's been a great year for wild senna, a legume that folds up its leaves at night.

When many of the midsummer native wildflowers are looking spent, autumn Helenium unveils an array of attractive yellow flowers.

Stalking Monarchs, and Encountering the Other Milkweed Caterpillar

Note: This post serves as a contrast to the horrific flooding in Houston from Hurricane Harvey, showing how stormwater can drive diversity rather than destruction, if we work with nature rather than against it. Unlike cities, the plants that grow in floodplains are built to pop back up within days or hours after a flood and just keep on growing and flowering. Most of these photos were taken in a detention basin, which is an acre-sized depression in the ground, dug to receive storm runoff from the Smoyer Park parking lot. The purpose is to "detain" the rain that hits the asphalt and that would otherwise rush into the nearby stream. Detaining the water reduces flooding in downstream neighborhoods. The detained water then either seeps into the ground or is slowly released through a small pipe into the stream after the floods have receded. 

Last year, a collaboration of federal and local governments with the Friends of Herrontown Woods converted this mowed basin into a wet meadow with floodplain plant species that thrive with these periodic pulses of runoff. Without regulations requiring it, the concave setting for this lovely oasis for native plants and pollinators would not exist, and the polluted runoff from the parking lot would have flowed straight into the local stream, contributing to flash floods.

Nature has offered up some surprises, here in the doldrums of summer, when people who aren't somewhere else sometimes feel like they should be. There was the unexpected, and unexpectedly affecting, chance to capture family portraits of black vultures in the previous posts; the weather has been unexpectedly cool; rains have come when needed for the third year in a row, and monarchs have proved resilient, rebounding from their diminishing numbers in recent years. Not many, as yet, but more.

Thinking them elusive creatures, I figured a zoom lens was necessary to capture their image. First came a peekaboo shot on the far side of a thistle at the Smoyer Park detention basin that we converted last year to (mostly) native meadow.

The blooms of Indian grass got pleasantly in the way of this shot.

With nowhere else to go in a sea of soccer and baseball fields, the monarch kept circling around the planted meadow, encouraging patient waiting for a chance at an unobstructed view. Finally, a clear shot from 100 feet away, while it perched briefly on a river birch. Congratulating myself on some success with a powerful camera, I plunged into the meadow to weed out a small clump of foxtail grass that would become way too numerous if allowed to go to seed.

And there, five feet away from my tugging and clipping, landed the monarch, easily photographed with an iPhone,

with a coppery background of Indian grass. That's what weeding a wild garden does--it immerses the gardener, creating opportunities for serendipity to work its magic.

Just across Snowden Lane from the park, behind Veblen House where our Friends of Herrontown Woods group has fashioned a clearing by removing invasive shrubs and wisteria, another sort of caterpillar munched on the leaves of common milkweed, which has prospered in the resulting sunlight.

Displaying proper Princeton colors, the milkweed tiger moth needed every milkweed plant there, and then some. We came back a week later and found every milkweed stripped down to bare stems. The common milkweed's strategy of aggressive underground spreading becomes more understandable, given the voracious appetites of these caterpillars.

Also called the milkweed tussock moth, the caterpillars become more colorful as they grow. As an adult moth, they are said to retain the cardiac glycosides they pick up from eating milkweed, and warn bats of their unpalatability by emitting a click as they fly about at night.

With summer almost over, a first sighting of a monarch larvae--on a purple milkweed, of which there are very few in Princeton, for some reason. Common milkweed can be a bit too aggressive in a garden, and swamp milkweed disappeared from our garden after a few years. Purple milkweed with its showy blooms may be a good alternative, if we can find any seed after the hungry caterpillar is done.

A Sampling of May Flowers

No theme here, just flowers. Red buckeye, for instance, though this one doesn't look very red, a small tree planted occasionally along streets--this one under powerlines where it's small size should prevent it from tangling with the lines in years to come. It's native, though the only time I saw it growing in the wild was in the coastal plains of North Carolina.

Adding to the red end of the spectrum is a Rhododendron at Veblen House. We recently moved a carefully excised portion of the last known and deeply shaded native Rhododendron in Herrontown Woods--an azalea species--to the botanical garden next to the HW parking lot, to see if it might grow, thrive and bloom once again, if given some light and tlc. Native azaleas are said to have been a common sight in the past along the edge of Herrontown Road.

Princess trees are an introduced species often found along interstates. There are several growing at Herrontown Woods that we're leaving to grow for now. They bloom before leafing out.

The Japanese and Chinese wisterias also bloom before leafing out, making for a striking display if contained. If not contained, they become a menace, spreading into woodlands where they smother and weaken trees, and so dominate that nothing else can grow. Fortunately, they don't seem to spread by seed. Otherwise, Princeton would have long since been engulfed. There is a native species of wisteria that grows in the southeastern U.S.. It blooms when the leaves are already developing so is less spectacular. It is less aggressive, but even so must be planted with caution. Other native vines like virgins bower, groundnut, and Virginia creeper may not dominate in the wild, but can be surprisingly aggressive in the less competitive environment of a garden.

Fringe tree is a lovely native shrub, rarely seen in the wild. My one encounter was on some land we preserved in Durham, North Carolina. This fine specimen grows in a carefully tended garden at Franklin and Snowden in Princeton.

A less tended example is in Community Park near 206.

More common than fringe tree are native black locust and black cherry, both of which have white flowers around now. Black locust's flowers are usually high up, but this specimen along Herrontown Rd were low enough to photo. The tree has yellow, rot-resistant wood useful for fenceposts and burns clean and hot in the wood stove. Towering specimens grow near historic houses in the area, which doesn't seem a coincidence.

More whiteness comes from Deutsia, a well-contained shrub sometimes planted as a low hedge. Not native, but doesn't seem to spread into wild areas, or even in the yard.

Everyone knows flowering dogwood, made bright and beautiful by its bracts.

Sad to see many older flowering dogwoods in my neighborhood dying back and ending up as dead wood piled in the street. The loss, either to old age or to an introduced fungus that causes anthracnose, heightens the appreciation of those that survive.

Far more rare and less known than the flowering dogwood is the alternative-leaved dogwood, only two specimens of which I have encountered growing in the wilds of Princeton, at Herrontown Woods.