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Conservation IssuesThe Sourlands: A Treasure in Our Midst
Pat Sziber

The Sourlands: A Treasure in Our Midst
Pat Sziber

We at Washington Crossing Audubon have an ecological, geological and historical treasure within our midst. The Sourland Mountain region falls entirely within our chapter area, from its northeastern flank in Somerset to its western terminus in Hunterdon and Mercer counties. This roughly 90-square mile region includes parts of Hillsborough and Montgomery Townships and runs diagonally through Hopewell Township, brushing by Hopewell Borough on the way, cutting through East and West Amwell Townships to Lambertville, where it disappears into the Delaware River to create a treacherous run of rapids.

The region is a geological wonder, formed by volcanic upheaval during the late Triassic Age. Its characteristic gray diabase rock, so prized by quarry companies for crushed stone and rip-rap, resulted when magma poured into pools beneath the existing sedimentary rock and slowly cooled. As the softer rock weathered away, the diabase intrusions became exposed. The Sourlands are famous for the enormous boulders that litter the landscape and, in places, are packed densely together to form boulder fields. By the way, the boulders were not dropped by retreating glaciers-the glaciers never got quite that far-but rather they are thought to have been formed by erosion of the diabase intrusion.

How fortunate we are to have this wonderful resource so close at hand. How awesome the cloak of responsibility we must share as its stewards. The Sourlands encompass the largest contiguous forest in central New Jersey, along with a diversity of other habitat types. It contains an extremely fragile groundwater system, gives rise to the headwaters of several streams, and holds wetlands and vernal ponds related to its perched water table. It provides nesting habitat for many bird species and critical habitat for neotropical migratory songbirds such as scarlet tanager and chestnut-sided warbler. It also is an important stopover site for migrating birds and hosts a full slate of over-wintering species. Undisturbed areas harbor a number of plants listed by the NJ Natural Heritage Program as endangered or species of concern, such as the three-inch tall pennywort, the delicate, rambling Allegheny vine and the lanky yellow giant hyssop.

The Sourland Planning Council has embarked on an energetic campaign to save the Sourlands by promoting sound planning. They were awarded a Smart Growth grant by the NJ Department of Community Affairs, for which WCAS wrote a letter of support. The money is being used to develop a Natural Resources Inventory (NRI) for the region. The group is currently putting together a picture map of the Sourlands. And they have published a beautiful, informative book, New Jersey's Sourland Mountain by T. J. Luce, focusing largely on the history, geography and folklore of the region and full of photographs and maps. Several nonprofit land trusts, along with state, county and municipal governments, have been very actively pursuing land preservation in the region.

WCAS has had a special association with the Sourlands since the early 1990's when several of our members helped with the Baldpate Mountain biological survey and, then, in 1994 when the chapter conducted the year-long Sourland Mountain Preserve Biological Inventory and put together a report for Somerset County. A breeding bird survey conducted in 1990 showed that Baldpate harbors a notably large number of migratory breeding birds who are forest interior specialists. The SMP survey revealed an astonishing 8 species of state listed plants along with an impressive list of bird and other animal species. In 2003, our volunteer biologists spent another year in the field at Alexauken Creek Wildlife Management Area in West Amwell. The report of that survey is currently in draft form. These data provide a foundation for habitat management plans and supply key information on flora and fauna that is needed to complete the natural history picture of the Sourlands. Our own board member Hannah Suthers has collected the most intensive data that exists for the Sourlands at her Featherbed Lane Avian Research Station near Hopewell. Hannah's work underscores the importance of habitat diversity and patch size.

What you can do: Let us, as a chapter and as individuals, commit ourselves to protection of the Sourlands. Get to know Sourland Mountain! Be adventurous and take a drive along its winding roads, which are unpaved in places. Get out and walk some of the incredible preserved open spaces. The website http://njtrails.org has information on a couple of Sourlands trail areas and more will be added. If you see something special during your peregrinations, please let us know. Become an advocate for open space preservation. If you live in a Sourlands community, speak up at municipal meetings in favor of protecting the region. Keep and eye out for special events in the area, such as lectures and exhibits. Contact Pat Sziber at conservation@washingtoncrossingaudubon.org with any special sightings or to be added to a Sourlands Update e-mail list.



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Last revision: Friday, May 28, 2004 - 11:43:51 AM