The Disappeared Sandplains: 95 percent of them are gone
I trudge along a barren, sandy field, following a bespectacled, gray-bearded ecologist named Bill Moorhead. He steps carefully in his work boots over dead patches of grass and green-grey lichen. He leans down suddenly, plucks a dead plant out of the sand, and holds it against the worn-green canvas of his work coat. I peer at the dead, orange-tinged seeded tops of St. John’s wort (Hypericum gentianoides).
He holds the wispy dry leftovers of a grass (Aristida tuberculosa) that survives on these sandy soils because of its three wing-like seeds, or “awns.” These catch the loose soil as the wind drops the grass. The awns fix themselves in the sandy soil, ensuring the growth of the next generation.
This is not the beach. This is not the desert Southwest. This is a sandplain somewhere in central Connecticut. I have raced across a state highway, skirted a fence, and crossed railroad tracks behind Mr. Moorhead. Behind the sandy field and its dead grasses and lichens rises an industrial building. Now we walk around an intriguing bull’s-eye-shaped indentation in the whitish sand.
Because this habitat I’m visiting is so rare now, I have agreed not to talk about where exactly I am, but I am curious to know what species made this odd circular wallow. “People,” he says. “An ATV.” Homo sapiens did the usual ritual of circling around in an all-terrain vehicle. That shocks me a bit, until I learn that as long as a joy rider doesn’t do that all the time—say, as long as the ATV driver comes back here only once every few years—then the disturbance might even help this landscape. I have much to learn.
Degraded and Diminished
This is a sandplain grassland, sometimes called a sand barren, one in a list of “imperiled ecosystems” grimly catalogued several years ago by a plant expert, Kenneth J. Metzler, and an insect expert, David L. Wagner, both of them state of Connecticut scientists, explaining to a governor’s taskforce what rampant development and other human degradation had done to the diverse habitats of southern New England.
A sandplain is a dry deposit of sandy soil left by glacial deposits and historically maintained by disturbance. The main type of disturbance was fire, which encouraged certain plants and trees to thrive on that dry land. In modern times, even if the sandplains were still extant, burning them regularly would not fit any kind of safety policy of most municipal and state officials. But the sandplains woes go way beyond the lack of regular fire.
Dr. Metzler, a former state heritage biologist who identified and mapped critical habitats for state databases, said that so many sandplains have been lost to development or degraded by adjacent industry that he had “written off the sandplains as being nonfunctional, until I met this fellow named David Wagner.” Dr. Wagner, an entomologist and professor of ecology at the University of Connecticut, found rare beetles living on sandplains. The insects thrived in soil so heavily altered by people that it was little more than a collection of sandpits, but “they had these cool tiger beetles living in them.”
It’s difficult to calculate exactly the acreage of Connecticut’s sandplains before development, but Dr. Metzler estimates that only about 5 percent of the original sandplains are still sandplains. This may seem an obvious point, but I ask Mr. Moorhead if, once industrial buildings, shopping malls, houses, and pavement cover sandplains, is the habitat totally lost? The answer: yes.
Developers have loved sandplains because they’re flat. They don’t hold rocks or roll around large hunks of rock ledge as many Connecticut landscapes do. The earliest development of sandplains was making them into cemeteries. In modern times, they provided level areas for huge complexes such as Bradley International Airport in Windsor Locks, the University of Connecticut’s stadium at Rentschler Field in East Hartford, and the former Cytec Industries in Wallingford (now closed)—all were built on sandplains.
Several acres of sandplain remain undeveloped around the Cytec property, Dr. Wagner notes. This is the largest undeveloped sandplain left in the state. And, like most of the sandplains, it is in private hands. This Cytec property went up for sale this winter.
The Original Sandplains
Before European colonization started in the 1600s, this sandplain —and the many miles of others to the north and south of where I stood the day I visited the sandplain with Mr. Moorhead—could have been covered with pitch pine trees. Those low, gnarly trees thrive on sandy soil. And beneath them, at that time, probably were similar grasses to the ones I review with Mr. Moorhead. The land would have burned every several years because the Indian tribes who lived here used fire to keep their hunting and migration routes clear, and to produce fresh grass for meadows.
Or the land could have been open and somewhat barren, as parts of it appear to me the day I rambled around it. Whether once home to the low pitch pines or the grasses, we know for certain that this sand has been here for about 12,000 years, since the time a gigantic lake retreated.
The lake was known later as Glacial Lake Hitchcock (for the geologist who studied it). For some 3,000 years, it held water for miles on either side of today’s Connecticut River, extending from today’s Rocky Hill, Connecticut, to northern Vermont. The lake’s layers of sand and silt settled as a result of the lake’s movement and ultimate draining after the landscape altered.
Stanley W. Bromley imagined some of this scene in his 1934 article, “The Original Forest Types of Southern New England” (Ecological Monographs, vol. 5 no. 1, January 1935). Most of Connecticut was forested by very old trees with a “parklike” landscape beneath, he wrote.
A few years later, in 1937, Charles E. Olmsted studied sandplains for his Yale dissertation. He proved in a paper published that year, “Vegetation of Certain Sand Plains in Connecticut” (Botanical Gazette, vol. 99 no. 2, December 1937) that sandplains’ plant make up can change easily by seed distribution. Birds, wind, people’s shoes, and nearby farmers planting shrubs along fencerows—all can change the make up of the plants and therefore animals.
Dr. Olmsted identified the then-largest swatch of sand barrens, as the sandplains also have been called, from North Haven and Wallingford north to Meriden, 1.5 miles wide and 15 to 16 miles long. That the land remained barren, favoring small groups of drought-tolerant, sand-loving plants and animals in a state where almost 46 inches of rain fell in a year—this proved, he wrote, that the barren landscape represented a land not modified by people. He believed that grassland persisted on the sandplains until the European colonists came along and encouraged pitch pine and scrub oak.
His paper also documented how farmers had degraded sandplains. They tried to grow crops that weren’t suited to the soil. The farms failed, and they abandoned them but didn’t take away seeds left from their failed crops. This disturbed seed banks in the sandplain soils, and discouraged, in turn, those plants that would thrive on sandplains.
A Vulnerable Ecosystem
Seldom do the remaining sandplains appear in the best condition they can be. Optimally, they are home to several pollinating insects, all of them either listed as Connecticut species of special concern or no longer found here. These include the noctuid moths Apamea burgessi, Agrotis stigmosa, Eucoptocnemis fimbriaris, Lepipolys perscripta, and Euxoa pleuritica; the violet dart moth (Euxoa violaris); phyllira tiger moth (Grammia phyllira); the frosted elfin moth (Incisalia irus); and the regal fritillary moth (Speyeria idalia); and Leonard’s skipper (Hesperia leonardus), a tiny fast-moving butterfly that lives for only two weeks.
The sandplains also provide the unique dry habitat for certain plants. These include sandplain gerardia (Agalinis acuta), which the state Department of Energy and Environmental Protection lists among the “most important” to protect in its 2015 Wildlife Action Plan and which is endangered in the United States; low frostweed (Helianthemum propinquum, and golden-heather (Hudsonia ericoides), both endangered in Connecticut; and others.
Animals that thrive on sandplains struggle, too. One of the rarest toads in Connecticut, the eastern spadefoot toad (Scaphiopus holbrookii), likes to hide in sandy holes after breeding in temporary pools. We know it’s out there on the sandplains. Grassland birds that live in this habitat include the state-endangered Northern harrier, grasshopper sparrow, savannah sparrow, and upland plover. We can’t list them all here. See the Connecticut habitat listings in the Connecticut Wildlife Action Plan, best found through an online search.
Dr. Metzler mapped critical habitats used in these reports and others, and says it’s a shame more of the public doesn’t know about the maps. One can search online for “Connecticut critical habitats,” and that will usually lead to the database. Or go to this URL to get started: cteco.uconn.edu/metadata/dep/document/CRITICAL_HABITAT_POLY_FGDC_Plus.htm.
Sandplains aren’t going to thrive as the total ecosystems they used to be. Dr. Wagner says some scientists have given up hope. Mr. Moorhead and Dr. Metzler are two who look at the future with a sense of possibility, if a diminished one.
Before Dr. Wagner showed him the tiger beetles burrowing around in degraded sand pits, Dr. Metzler says, “I was looking at it from what I considered a viable ecosystem perspective in the plants and size. My mind was changed.” Now he considers the few remaining sandplains “as remnants that function with a few species that are indicative of that type of habitat.”
If seeds have been waiting in the sand for their right moment, and the land remains free of development, the sandplains could harbor some of the unique flora and fauna they once did.