Methods

Parkwide Cultural Landscape Inventory Process

Park staff are currently working with the cultural resources specialist for the National Park Service Northeast Region to develop a cultural landscapes inventory. Delaware Water Gap National Recreation Area will be a test case within the park service for doing this work on a parkwide, landscape scale. Inventories will also be completed at a much smaller scale for the individual (formerly private) properties that now make up the park. This work is being made easier because a historic resources study was completed for the park in 1996; it identified six themes (including transportation, agriculture, and settlement patterns), as well as the properties associated with those themes. Staff are now identifying the specific landscape features (such as orchards, field patterns, and transportation corridors) that contribute to any one of the themes in a specific portion of the park.

As part of the process for developing the landscape-level inventory, a set of 1939 aerial photographs for the park is being geo-rectified (see explanation in Tools and Approaches below). Using GIS, these maps are overlaid on a set of 1992 digital ortho quarter quadrants (DOQQs) for the park and a spatial analysis completed to see how certain cultural landscape characteristics have changed over time. For example, if resource managers examine open fields, they will be able to see areas where there has been forest encroachment. Because open fields have been determined to be an important cultural landscape characteristic, resource managers might choose to target some of these areas for tree removal. Other characteristics that could be examined would be farm clusters, field patterns, and transportation routes.

Once this inventory is complete, the cultural resource staff will work together with the natural resource staff to see where there is overlap in their interests. For example, special efforts might be made to clear wooded areas to maintain the traditional agricultural pattern when those areas have also been identified as valuable grassland habitat.

Agricultural Leasing Program

The encroachment of forest on open fields is a very real threat to the cultural landscape. Park managers realize that, in order to preserve the historic landscape, they need to maintain two characteristics: the open, patchwork character of cultivated fields, pastures, hedgerows, and stone field fences, and the historic agricultural land use. To do this, the park instituted an agricultural leasing program in the early 1980s, leasing federally owned lands back to local farmers. Currently nearly 3,000 acres of agricultural lands, both meadows and cultivated fields, are leased to farmers under 26 special use permits. The criteria set by park managers initially stated that only lands that had historically been farmed would be part of the program, and that character-defining features of the fields would be identified and preserved. This meant that the open field character and historic field sizes would be maintained, along with stone field fences and vegetated field boundaries. As a term of the lease, a farmer agrees to maintain field edges, including stone fences and hedgerows, and to control or remove invasive exotic vegetation. Farmers also consent to use the lowest-impact farming methods possible. In order to keep farmland open, farmers must also agree that for every acre put into crops they will brushhog an equivalent acreage of field every three to five years, which amounts to 1,500 acres kept open.

Farmers wishing to lease land within the park are faced with two challenges: the historic field sizes are smaller than what modern farm machinery would dictate to be profitable, and the demolition of most farm buildings in preparation for the dam and reservoir has left nowhere to store farm equipment. In order to make the leases profitable, park managers have made concessions to farmers. Instead of the standard practice of leasing to the highest bidder, park managers lease land to good farmers who pay a lower lease rate but are willing to embrace park management goals.

Because the environmental effects of agriculture can be in direct conflict with the preservation of cultural and natural resources, park resource managers work directly with farmers to determine best agricultural practices. Initially this meant that farmers were encouraged to use the no-till method of cultivation in order to reduce soil erosion. Then, as the use of herbicides became more of a concern, farmers moved toward reduced-tilling and tilling (i.e., plowing). A long-term goal of the park is to make the transition to organic techniques.

Further modifications to the agricultural leasing program were made as park managers learned more about archaeological resources. In 1993, the Minisink Archaeological Site National Historic Landmark district was designated along the Delaware River, and park staff were concerned that some of the farming practices used on leased agricultural fields there could damage subsurface artifacts. Park managers again worked with farmers, experimenting with various tilling methods. Disk tilling was found to be harmful, so, working with integrated pest management specialists, the park developed a no-till regime with reduced herbicide use that would protect artifacts and be safe for the environment. In fields where artifacts are very close to the surface, crops are replaced with warm-season native grasses that do not require cultivation. The established native grass fields are mowed just once a year and do not require soil amendments or pesticides.