Thursday, October 22, 2020

The Work Behind a Natural-looking Meadow--Smoyer Park in Princeton

Sometimes, maybe most of the time, natural takes work. This goes for both nature and human nature. Most people will look at this wet meadow, with its stand of ironweed set off by goldenrod in the distance, and think it burst spontaneously from the ground, fully formed. But that's not the case. 

There are places where native diversity happens without intervention. I've known a few, where the original hydrology is intact, and introduced species have yet to invade, and fire is allowed to sweep through periodically and beneficially, as in ancient times, and the soil still holds within it the seeds to feed all the stages of succession, from field to shrubland to forest. 

But not here in the middle of Smoyer Park, which had been a farm before it became ball fields. Plowed, regraded, planted with exotic turf grasses, this land had long since lost its native seed bank. Soil has a memory, as do we, composed of all the seeds that have fallen there and have yet to sprout. That memory is erased when plowed or bulldozed, as so much of America has been. Into the void will fall the seeds of mostly nonnative, weedy species that will lead to discouraging results for anyone who tries a romantic "just let it all grow" approach. 

Bringing back natural, then, takes work. For an analogy, think of all the parenting needed to raise a child, all the emotions that need to be understood, the impulses that need to be steered in a healthy direction, all the parts of self that can get buried and forgotten along the way. There's plenty that can go wrong during that perilous journey to adulthood, and if it does, even more intervention is needed to regain that sense of comfort within one's own skin. 

Nature has been profoundly traumatized, and yet many people somehow expect it to spring back without ongoing assistance. As with parenting, it's hard to have success in the absence of love. Most of the world's love and attention is directed somewhere other than towards nature, which explains why our suburban landscapes seldom receive more than custodial care--weekly visits of mow, blow, and go by crews indifferent to the land and its promise. 

This photo shows what the wet meadow looked like just after it was planted with native grasses and wildflowers four years ago. Many would assume that nothing more was needed to create a healthy meadow, and would have walked away thinking "mission accomplished." But as with a baby, birth is really just the beginning. I looked upon the detention basin's bare expanse, seeds planted but yet to sprout, with an eye for all that could go right and all that could go wrong. Over time, it has taken only a couple hours of attention now and then to steer the planting in the right direction, but those few strategic hours, catching problems early, has made a big difference. In a sense, the planting resides within me. It is part of my internal calendar, rising into my thoughts often enough to prompt action. 

Here is an account of the many kinds of plants that can make things go right or wrong when a detention basin is converted from exotic turfgrass to native meadow. (Click on the "read more" to continue.)

The backbone of the initial planting, which was done by a federal agency, Partners for Fish and Wildlife, was various prairie grasses. What has survived is the big bluestem, a.k.a. turkeyfoot (a certain resemblance to turkey feet sticking up in the air), 
and Indian grass, 

which has beautiful golden anthers when blooming. Though I've seen Indian grass bloom in fall from seed planted in spring, this detention basin planting looked pretty bare the first year, raising concerns that the conversion to natives would fail. By the second year, though, the grasses were starting to fill in.

Two species of wildflower in the original seedmix provided an early show of reassuring color. Black-eyed Susans were dominant early on, 
along with partridge pea. Neither of these is very common in the wild, so it's not surprising that they have dwindled in number to but a few, having served their early purpose in the planting.

Other vestiges of the original seed mix are blue vervain
and one specimen of oxeye sunflower. 

A few oddities like these popped up this year, 
as if someone spilled a packet of random wildflower seed designed for quick color but unrepresentative of the local flora.
To get more indigenous species growing, girlscouts conducted a "seed bombing," which involves mixing local wildflower seed I had collected with some of the resident mud, then sending the mud balls flying into the basin. 

This rose mallow hibiscus likely sprouted from that planting spree,
along with a Joe Pye Weed,
a New England aster,

wild senna, which will likely be left alone by the deer,

and a local sedge.
Other wildflowers that have found their way in are a St. Johnswort, 
and some monkey flowers.

Jewelweed is a native annual that is starting to show up, which will be good news for hummingbirds.

Sensitive fern has popped up as well.

The goldenrods, which likely blew in on their own, have been particularly resonant this year, but the local goldenrod species tend to spread underground and could displace other natives over time. 

The biggest threats to balance, though, are a host of nonnative invasive species with uber-powers to crawl over everything if not deterred. Stiltgrass, of course, which probably was in the surrounding turfgrass before it spread to the meadow planting,
and a similar invasive called carpgrass. 
Chinese bushclover, as with mugwort, will form monocultures if allowed, and must be removed or otherwise killed before it goes to seed. 
The chinese bushclover's white flowers and leaves are distinctive. 

Canada thistle is another invasive weed that could spread aggressively if not countered. It's been the ruin of many a neglected garden around town.

Porcelainberry is the most aggressive invasive of all, and is now starting to seed in, probably from an infestation elsewhere in Smoyer Park that has been allowed to grow unchecked. This vine, perhaps more than any other, could smother the whole meadow if not removed.

Less of a threat is this foxtail species that is easy enough to pull and remove before its seeds can mature. I did a lot of pulling of this early on, when it tried to claim the bare ground.
What to do with pilewort, a native annual weed named for its white puffy seedheads that seem like piling for a pillow? The flowers are what you see there, essentially colorless, but visited by bees. I've left it to grow unfettered, hoping that it will fade away in time as perennials grow in. 
Some big thistles, probably not native, don't seem to be taking over and are popular with the pollinators and the birds.

Nut sedge is also being left to grow for now. It can take over gardens, pulling easily but spreading underground, but hopefully won't prove too competitive here.

The wet meadow can also be thought of as akin to a playground, where the monitor is keeping an eye out for bad actors--bullies who don't play well with others. My job (self-appointed and unpaid, since the world's money goes to mowing rather than tending to complex plantings), is to catch the aggressive plants before they go to seed or spread underground, and to add more native species that are likely to thrive without taking over. To do so means knowing the look and behavior not only of the intended plants but also the unintended ones that come in on their own. If all goes well, the plants and pollinators will flourish, and a passerby will stop, admire, and take a photo, thinking it all natural. 

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