Unfragmented open space blocks are undeveloped sections of the landscape with few or no roads. These unfragmented areas can include forested areas, open water, wetlands, and agricultural lands (and may include gravel pits and clear-cuts as well). These blocks are unrelated to ownership boundaries. Unfragmented lands have significance for wildlife habitat, as well as identifying large areas of open space that are also suitable for outdoor recreation, protection of water resources, etc. The size of these unfragmented blocks of land varies depending on the location. For example, in southeastern New Hampshire where there is a high level of development, an unbroken block in the hundreds of acres is significant. In northern New Hampshire, where there has been less development and there are large timberland areas, significant unfragmented blocks are much larger, in the thousands of acres.
Basic NRI - What to Include:
Unfragmented Blocks is an analytical map, rather than an actual resource. Unfragmented blocks information can be mapped using NH DOT or USGS data on roads available in GRANIT. Check how recently the road data being used were updated and if private roads are included in the data.This analysis should exclude all NHDOT Class 6 roads, and USGS Class 5 roads because these types of roads aren’t considered significant barriers to wildlife (and many of them can be regarded as trails). Using GIS, the remaining road classes are "buffered" by a 500 foot width, where it is assumed that most development occurs. This results in unfragmented areas characterized by little or no development.
Areas can be categorized according to block size, e.g., 250-500 acres, 500-1,000 acres, and 1,000+ acres. The number and size of unfragmented blocks will vary for each community, depending on the existing level of development and land fragmentation. Urban areas may find only a few unfragmented blocks, and those that exist may be small. More rural areas could find blocks of 1,000 acres and more. Since some unfragmented blocks may extend across town boundaries, it is advisable to include the adjacent towns in the overall analysis.
Basic NRI Maps:
Epping Unfragmented Blocks map example
Note that the NH Wildlife Action Plan Highest Ranked Habitats Map provides information about unfragmented blocks as well.