An empty firewood stand and a mailbox are the lone markers viewable from the road. The mailbox address numbers are faded, some completely, but otherwise spell “2150 Amwell Road” — just east of Millstone Borough.
Turning in, one passes underneath a wooden arch swallowed by overgrown shrubs. Further up, a post board confirms that this is not some stranger’s driveway but indeed the Hutcheson Memorial Forest Center — a 60-acre grove of old-growth forest, also known as Mettler’s Woods.
“This is the most studied piece of land in North America,” says Steven Handel, the director of Hutcheson and a distinguished professor of ecology and evolution at Rutgers. “There are more than 400 permanent research plots in Hutcheson.”
It is also a significant ecology and conservation research center, one the general public can only access through guided tours on selected Sundays — including August 20.
Hutcheson’s patch of uncut forest lies within more than 500 acres of younger forests and former agricultural fields, all under the stewardship of Rutgers University. It was named by the National Park Service in 1976 as a National Natural Landmark for its “exceptional value as an illustration of the nation’s natural heritage.”
Hutcheson was formally preserved by Rutgers University in 1955 after developers and a timber company eyeing the uncut trees threatened the woods.
The United Brotherhood of Carpenters and Joiners made a donation to secure the acquisition of the property, subsequently named after William L. Hutcheson, a past president of the carpenter’s union.
The presence of a virgin forest may suggest a sense of permanence, but, say its stewards, in ecological circles Hutcheson is known for being a research site on “succession,” the study of how plant communities change and transition through time.
After Rutgers acquired the property, adjacent plots of farmland were “released” and returned to natural processes. An influential study started by ecologists Murray and Helen Buell in 1958 documents the succession of old fields and to this day researchers return yearly to measure plant species.
Handel and Max Piana, Hutcheson’s on-site land manager and an urban ecology doctoral student at Rutgers, begin their tours in the old fields surrounding the old forest.
Here rectangular parcels sit side by side in various stages of plant succession. Early stage fields are covered with long-stemmed goldenrod perennials, their thick flower clusters swaying alongside asters and fern-like sumacs. Looming over the grassy plants are Russian olive trees, an invasive species with distinctive silver-shiny foliage.
Another field’s takeover by evergreen cedar trees and some maple trees indicates a later stage of succession. The young forest will eventually shade out the colorful perennials, as well as the sun-loving Russian olive. Late stages of succession will be marked by oak and hickory trees. “You should come back in 50 years and see,” Handel says.
Handel has taught at Rutgers for 32 years and says at least 50 percent of the old forest was once covered by mapleleaf viburnum, mid-sized shrubs with white flowers and dark berries that are often confused for maple trees. Today the shrubs are virtually gone, devoured by deer.
Handel calls suburbia the “perfect habitat” for deer, which feed on manicured grass lawns without fear of any hunters or predators, cars notwithstanding. The deer population exploded beginning in the 1970s. Density went from a handful of deer per square mile to nearly 100 deer per mile in some areas of New Jersey today.
“This is nature out-of-sync. The natural checks and balances are not there,” says Handel. “Once you lose the understory, that’s habitat for animals, and the whole food web is destroyed. The soil dries out and that stresses the trees.”
Now the overseer of an ancient New Jersey forest, Handel grew up in Far Rockaway, Queens. His father was a Polish immigrant who worked in a garment factory and his mother was a housewife.
After college at Columbia Handel taught biology at a Manhattan private school for a few years. He became “re-enthused in biology” and pursued graduate studies at Cornell.
A longtime ecologist, in recent years Handel has also channeled his expertise on plant populations into urban restoration, for example, turning a landfill back into green space.
“The need for ecology in cities is enormous,” Handel says. “It’s not just about prettier. Plants can play a significant public health role, making cities healthier, cleaning air, groundwater, and making it more livable.”
Hemmed in by decades of suburban development, Hutcheson provides insight into how to keep a forest alive and thriving.
“From studying Hutcheson we can learn what’s possible and learn about problems and how to keep them under control,” says Handel.
With the construction of a two-mile deer fence encircling most of the forest — funded by a former student of Buell and matched by the university — researchers are observing whether native plant species can recover. The goal is regenerating the forest to match its pre-suburban state.
Crossing through the deer fence and into the old forest, one notices the entire floor is shaded and considerably cooler than the adjacent fields. Visitors follow an old growth trail, a loop that meanders through quiet forest. The solitude is visually punctuated by huge oaks and hickories, which tend to be spaced apart.
White oaks, one of four different oak species in the forest, and its scaly, block-like gray bark are dotted throughout. Hutcheson’s website says the average age of a living white oak tree is 235 years. They stand in contrast to the darker, lengthier grooves of a red oak trunk. Thick vines of wild grape and poison ivy snake up and around the trunks of many trees, chasing the sunlight at higher altitudes.
The old growth oak and hickory trees are not nearly the size of the famous old-growth redwoods at Muir Woods in California. In addition to differences in tree species, Piana says soil conditions are not ideal. However, both Piana and Handel say the undisturbed soil is a unique aspect of the old forest.
A half-fallen tree with exposed roots reveals only 18 or so inches of soil. Underneath is shale rock. Moreover, unlike street trees in relative isolation, trees in the uncut forest must compete for nutrients and sunlight.
“It’s not all about stature, but the trees are big for its conditions,” says Piana.
The Mettlers were Dutch settlers who acquired the land in 1701. For reasons lost to history, the family plowed over the surrounding tracts but left today’s old forest untouched. This was highly unusual. European settlers typically cleared forests for farmland and pasture, and the groves of trees allowed to stand were ultimately harvested as wood lots, a ready supply of construction material and fuel.
No trees have ever been harvested for timber, but that is not to say the woods have been free of human influence.
Piana says the forest was under “active management” by Native Americans. Annual growth rings within the trunks of old trees reveal that Native Americans burned the forest site at 10-year intervals.
The regular burnings indicate a clear intentionality, and Piana says this type of forest management may have yielded a number of benefits for Native Americans. Routine burnings improve hunting conditions by clearing the understory and improve the productivity of select plants such berry bushes. It also privileged the growth and proliferation of oak and hickory trees, which are more resilient to fire than other tree types. Moreover, the preponderance of oak acorns and hickory nuts could have in turn attracted desirable game.
In other words, the current constitution of today’s oak-hickory forest may be a legacy of Native American land management. Yet while Hutcheson’s website refers to Mettler’s Woods as a “primeval, mixed oak forest,” the uncut stands are not quite a time warp into colonial-era New Jersey.
The winds of Hurricane Sandy took out quite a few of the older trees. Considered a “natural process,” the trunks fell in similar directions and have been left to lie.
Piana says the natural lifespan of an oak is 300 years, and Sandy was the knockout blow for quite a few older oak trees. For those interested in longevity, there are several American beech trees — easily identifiably by their smooth, elephant-skin bark — dispersed in the forest. Those can live for 1,000 years.
When a tree crashes to the forest floor, it can open up a patch of sunlight. Non-native species are quick to capitalize on the sunshine and swarm over the dead trunk, crowding out a baby tree from growing in place of the mother tree.
Deer also tend to avoid invasive species, which are pricklier and less tender than native species.
“I look at the ground and I get mortified,” Handel says. “Because of invasive species, the total number of (native) species goes down and down.”
By an accident of history, the uncut old forest at Hutcheson was preserved, but its future may be undercut by “letting it be.” Previous conceptions of ecosystems existing in a natural equilibrium have given way to the idea of plant communities as dynamic, constantly changing spaces. It is accepted that some form of human management is needed if native communities are to be preserved, and the deer fence was the first major human intervention.
Then there is climate change, a specter that dwarfs both marauding deer and invasive species.
“With climate change, it is warmer and drier, and this puts enormous stresses on plants,” Handel said. “I can’t promise palm trees in New Jersey, but we’re expecting big changes in the distribution of trees.”
For those weary of increasing urbanization in the human world, of the proliferation of luxury condos and nursing homes, tours of the old forest at Hutcheson can provide a peek at enduring remnants of New Jersey’s natural history. Yet like seemingly everything else, one of the oldest forests in eastern North America is caught up in change and an uncertain future.
Hutcheson Memorial Forest Center, 2150 Amwell Road, Somerset. Tours are offered on selected Sundays, including August 20 at 2 p.m. Free. Groups exceeding 10 people can request private tours. hmf.rutgers.edu.