Sunday, June 21, 2020

Cardboard Quells the Chaos--Renovating a Garden Bed

When plants aren't "playing well with others," sometimes one has to lay down the law. That's what happened in an area of the garden that got away from us. While we were off living our lives, Lizard's Tail, sunflower, and a common goldenrod were quietly sending their rhizomes out in all directions. Ground ivy and mock strawberry were overwhelmingly undertaking relentless stoloniferous expansions. And the once endearing, highly edible blue violets were pushing their way into every nook and cranny.

Some nature writers congratulate themselves on their tolerance for all living things, but that tolerant pose somehow doesn't extend to species that threaten people, e.g. COVID-19. A lot of the love gardeners feel for the plant world is expressed, ironically, by killing some plants that are threatening others. I may love red oaks, and can see that even poison ivy has an ecological role, but that doesn't mean I'm going to let a thousand seedlings take over a garden bed.

In extreme cases, where the desired and undesired become hopelessly entwined, or a garden path disappears in a sea of "way-too-much-of-a-good-thing" overgrowth, it's time to bring in the cardboard.

Yes, cardboard. Given all the negative forces in the world, cardboard stands out as a beneficent presence, rivaling that of chickens, or perhaps peanut butter, outstanding in its inborn capacity to do good with very little downside. Occupying a niche somewhere between wood and paper, cardboard can take myriad shapes to serve myriad purposes, whether keeping stuff together in a basement or rising into high art at a museum or on a stage.

In a garden, cardboard serves in a sprawled state, depriving weeds of sunlight, and creating a barrier that's strong and lasting enough that weeds can't push through. Some people use landscape fabric, but over time soil begins accumulating over the fabric, weeds grow on top, and the buried fabric then becomes a nuisance that needs to be pulled out and thrown away. Cardboard serves as a barrier for a season or two as it slowly decomposes, leaving no trace.

Here's the legacy of neglect, with path stones retrieved from the chaos,

and a tangle of way too aggressive sunflowers and violets. All are beautiful in their way, but hard to keep in balance with everything else.

Before laying down the cardboard, a few beebalms and lizards tail were retrieved from the mess with the intention of planting them elsewhere.

A variety of sizes of cardboard are useful. I put a few desired plants in--the sort that don't spread but instead grow in bunches--like ironweed, boneset, hibiscus, culver's root, tall meadow rue, cutleaf coneflower--then surround them with overlapping pieces of cardboard. More plants can be put in along the seams or by punching a hole in the cardboard. The walkway stones were put back in place, and other stones used to keep the cardboard in place until we can cover it with mulch.

Here, for instance, we're using cardboard as a base for a walkway around the "Veblen Circle" of native plants at the botanical garden next to the Herrontown Woods parking lot. A stone border is laid along one edge of the cardboard, and chips are placed on top, completely disguising the cardboard. The result is a weed-free path for a year or two. That's a whole lot easier than pulling each individual weed.

Friday, June 19, 2020

Towpath Nature Trail Loop in Late Spring

It's good to see a nature path well used and free of obstructions, which is the current state of the nature loop that winds through a wide section of the DR Canal State Park, just up the towpath from Harrison Street. (for posts showing the trail in different seasons, type the keyword "loop" into the searchbox for this blog) The whole area was being mowed until I convinced the state park folks to let the wildflowers grow, back in 2006. They then created a nature trail loop through the open woodland landscape between the canal and Carnegie Lake, and maintained it beautifully until a couple years ago, when they asked Princeton University to take over the mowing of the trail. PU actually owns the land, even though it's part of the state park, and they finally agreed to maintain the trail. I was out there with a chainsaw, doing what I could during the transition, given the tendency of trees to fall across the path.

As of June 2, the path was looking great, possibly due to university care, but thus far maintained more by foot traffic than anything else. Here's a plant-person's take on the interplay of native and non-native species to be found along the way.

Common milkweed is one of the few natives that can compete with the highly invasive mugwort. Both spread underground.

Bittersweet nightshade blooming on the shore of Lake Carnegie.

Blackberry flowers, with the green beginnings of the berry emerging as the petals fall.

Here, for comparison, is multflora rose, a nonnative shrub, more common than blackberry, with larger clusters of flowers, curved thorns, and lacking the linear grooves on the blackberry's stem.

Orchard grass blooming. Non-native but not very aggressive, often found as a single, erect clump here and there.

The orange-tinted remains of last year's broomsedge, which is not a sedge but instead a native grass, here lining the trail. Like other native prairie grasses, broomsedge is adapted for periodic fire, which its persistent stems encourage. A field of broomsedge can be very pretty after it turns color in the fall, though farmers associate it with poor soil.

Learn to recognize poison ivy in all its forms. It often looks glossier than other plants with three leaflets, reddish when young, with traces of red remaining in the stem later on. The pair of lower leaflets often show a "thumb" along the lower edge, a subtle version of which can be seen here in the mature leaf. People are surprised to learn that vines like poison ivy only bloom when they find a tree to climb up.

This is a hopeful sight for any lover of Joe-Pye-Weed, which will ornament the trail later in the summer in the patchwork of shade and sun beneath the scattered trees.

One of the dogbanes, which like milkweed will exude milky sap when you pluck a leaf.
Look closely at the photo below of Viburnum shrubs, and you'll see that the leaves of the one on the left are more distinctly toothed. That's the native arrowwood Viburnum (V. dentatum), while the shrub on the right is linden viburnum (V. dilatatum), a nonnative that has become surprisingly invasive in local preserves. As often happens, the native is seldom encountered, while the non-native is common, most likely due to deer preferring to eat natives.

If you know your plants, then you'll look at this small clump of leaves and feel happiness at all the yellow, cone-shaped flowers cutleaf coneflowers will produce later in the summer.

And even happier when you find a large congregation of cutleaf coneflower rising like a very slow-motion firework that will explode in color a month from now.

But knowing plants also allows you to foresee less auspicious trends, as the porcelainberry (NJ's kudzu wannabe) begins to grow up and over most everything in a smothering embrace. Persistent emails have yet to convince the university of the need to mow the field once a year in late winter, like state parks used to do. Annual mowing is the key to sustaining this open woodland of scattered trees lording over a vista of wildflowers.
There's a little parking just across the Harrison Street bridge. The trail loop is on the Princeton side of the towpath, just in from Harrison, with what looks like a birdhouse at the trailhead. Returning via the canal, I happened to see this yellow iris (I. pseudacorus), framed in the trees' reflection in the canal. The native iris sometimes seen is blue.

Saturday, June 13, 2020

The Many Blooms of June

There's a wooden heron that looks out on our backyard garden. I hope it's happy with its bay window habitat of orchids, christmas cactus and aloe vera, and pleased with all our efforts to steer the sun- and rain-drenched plant growth beyond the window pane.

The garden is a collection of mostly natives with a few non-natives mixed in. A garden and a mind are enriched, one by the other. A plant often has to first make it into the mind before it can find it's way into the garden, and the garden can surprise the mind with what pops up. Over time, both the garden and mind gain in variety.

It's been a particularly good year for the Virginia sweetspire, which along with its sweet spires has the added bonus of creating suckers near its base that can be dug and moved to new spots.

Elderberry makes up in berries and blooms what it lacks in grace. Maybe this year, being less distracted, and if the covetous catbirds cut us some slack, we'll set about harvesting the berries and making those delicious pies remembered from youth.

Most azaleas people see are evergreen and not native, but there are some wonderful deciduous native azaleas like this swamp azalea. Pinxter azaleas were once common in Princeton woodlands.

More subtle is the native Euonymus that are mostly browsed down to a few inches high in local woodlands by the deer. Their ornament comes later in the year, with the bright berries that give them the name Hearts-a-bustin. These I found locally, grew to size, and have begun placing in the "botanical garden" at Herrontown Woods, protected by cages. Otherwise they would be eaten down and never flower or make berries.

Even more subtle is winterberry--a holly that's growing in one of our miniponds. Our front and back gardens get a boost from runoff from the roof and the neighbor's yard, all directed into many shallow depressions where the water can collect and seep into the ground. Managed well, the puddles can serve as mosquito traps, luring female mosquitoes to lay their eggs, then drying out before the larvae can mature.

Sundrop flowers surround the leaves of richweed.

Fringed loosestrife seems a delicate and bashful native, with flowers pointed down, but has been a surprisingly aggressive spreader when placed in the protected, fertile environs of a garden. It may need to be planted in a shadier spot where it won't have so much energy to expand.

Beardtongue (Penstemon) blooming in a garden means it's also blooming out in the wild.

The deeper depressions we have in the backyard swale are populated by all sorts of plants that thrive in wet, sunny spots. This is royal fern, which stays in place, while sensitive fern tends to spread.

Many kinds of sedges provide a nice background texture. This one is fox sedge, which is less ornamental than fringed sedge and bladder sedge.

A personal favorite is soft rush, whose green "blooms" arise partway up the darker green leaf stems, like elaborate earrings. It's stems may be soft but it's a tough plant that can be found growing in ditches. Bring it into the garden and it achieves a graceful vase-like shape that makes for an accent that's both striking and subtle.

Botany teaches us to make distinctions, for instance between sedges and rushes--which look like grasses but aren't--and the many attractive plants that actually are grasses, like this deertongue grass, here shown next to a rising sea of jewelweed.

Fragrant Japanese honeysuckle always finds a way to survive our periodic attempts to discourage its rampancy.

Across the street, unfettered Japanese honeysuckle is overwhelming a hedge. Eventually, the hedge will die from all the competition, and the honeysuckle vine will play king of the slowly collapsing mountain as the suffocated shrub rots and buckles from the weight. Passerby will still think it's a hedge.

Coral honeysuckle--the native honeysuckle vine--grows along Nassau Street.

Meanwhile, back in the backyard, bottlebrush buckeyes are working on some spires,

and the oak-leaved hydrangias are getting ready to put on a show.

During a pandemic, it feels like such wealth to have nature close by, thriving through it all.

Tuesday, June 02, 2020

Late May Sightings in Herrontown Woods and Elsewhere

A runner named Nikolas who moved to town less than a year ago and, because he has considerable curiosity and runs rather than walks, already knows the area trails better than most of us, asked me what these are. He's been seeing them along paths in many places. They are the tips of tulip tree branches--a tree that grows to giant size and has distinctively shaped leaves and tulip-shaped flowers. It's sometimes called tulip poplar, and has a poplaresque look to it, but is actually in the ancient magnolia family. For some reason, I've never been very curious about why the tips of tulip trees end up on the ground this time of year, but Nikolas was. So I looked it up, and found out that squirrels bite off the tips, then drink the spring flow of sap from the cut stem as if it were a straw. No plastic straws for a squirrel, and it must be exciting to quench one's thirst while teetering at the end of a branch, 70 feet above ground. There's also a scale insect that can suck the sap from a tulip tree, then drops its aphid-like honeydew on the ground below, like a sticky rain. Fortunately, that's according to the internet rather than experience.

Very rarely, Jack in the Pulpits have this prominent venation. One nursery sells it as "Starburst."

Yellow star grass, seen now and then along trails, looks like a grass but isn't, in much the same way that blue-eyed grass looks like a grass but is actually an iris. Sedges and rushes are also plants that look like grasses but are not. Botany rewards those who take a closer look at things.

Wood briars have the latin name of Smilax and tend to have thorns and arching veins in the leaves, and grow up and over things. This one is less frequently encountered, has no thorns and supports its own minimal vertical ambitions. Called Smilax herbacea, apparently because it's more herb-like, its common name is carrion flower, named for the alluring aroma of its flowers, which I have yet to sample. Hinting at its preference for wet ground is all the jewelweed and stiltgrass seen rising from the ground below it in this photo.

Bladder sedge is one of the sedges with interestingly shaped seedheads that make up for the lack of color.

Have seen tiger beetles a couple times in Herrontown Woods this spring. They are speedy predators.

I happened to take a peek behind an ugly strip mall in Princeton Junction and found that where the expanse of asphalt ended, an amazing ecosystem began, filled with blueberries and sweet pepperbush and expanses of ostrich fern, growing beneath oaks and even a American chestnut that was hanging on. One could grieve for what was buried beneath the asphalt sprawl, or be astonished at what has managed to survive.

People often ask what the white flower is that grows a couple feet high and looks pretty but a little weedy. Daisy fleabane. (Betty Horn reminds me that there are a couple species of fleabane.)

This is what happens when you plant daffodils in spring rather than in the fall. They bloom in May and June.

Keena sent me this photo of a puffy golfball-sized growth on a white oak at the entrance to botanical garden taking shape next to the main parking lot for Herrontown Woods.

Turned out to be the tree's creative response to the wool sower gall wasp, which lays its eggs on oaks in the spring. The wasp "sows" its progeny, and ends up growing something wool-like in the process.

Red buckeyes are good to plant under powerlines, since they don't get very big, and would be an excellent tree to plant south of a house that has solar panels. People think that we must choose between trees and solar panels. No, just plant trees that don't grow tall, and one gets the carbon sequestration and cooling action of the tree plus the power generation and roof shading of the panels. That's what we call a "win-win."