University of Wisconsin–Madison

Wisconsin Geospatial News

Northwoods shows GIS progress

Bolstered by grant funds for competing the mapping of land parcels, several counties along Wisconsin’s border with Upper Michigan have been making large strides in recent years. County forestry departments have also become heavy users of the technology.

In addition, state and federal agency field offices have been increasing their reliance on GIS as a tool to support their various field and analysis activities.

As part of a recent trip I made to these northern areas, I was on one hand very impressed with the progress that has been made. On the other hand, it is clear that all of these users need to update their orthophotos but face serious challenges due to fewer and smaller available grants or cost-sharing programs from the state and national level.

Forestry use grows

Iron County is a good example of how the use of GIS has been absorbed into daily operations. Foresters have long used databases to track and project their management of forest lands by “compartment.” Linking this data with digital compartment maps and base layers such as orthophotos and hydrography is a big benefit. Adding visualization approaches such as hill shading (to create the illusion of landscape relief) will be another step forward.

GIS staff in a county forestry department may be asked to share their expertise with other county units. Last Mother’s Day, Neil Martinko of the Iron County Forestry Department was summoned to take part in a quick reconnaissance of a flood event caused by rapid melting of the remaining winter’s snow pack. He boarded a helicopter with a GPS unit in one hand and a camera in the other, and soon after was able to produce a map and slide show for county board members and staff showing effects of the flooding on bridges and culverts across the county.

At the Wis. Board of Commissioners of Public Lands’ field office in Lake Tomahawk, analysis of land ownership patterns is guiding a plan to consolidate scattered forested lands into larger blocks for more efficient management.

The next round of orthophotos?
The northwoods generally has 1-meter-resolution orthophotos with vintages from 1992-1998. Not only is this imagery aging but higher resolution (e.g., 2-foot or finer pixels) would deliver more benefits. This current orthophoto coverage was funded through a variety of sources, many of which are no longer available.

For instance, the Wis. Land Information Board granted funds to some counties to acquire their first orthophotos. At the time, that funding was available in block up to $100,000; however, the WLIB has not had that kind of grant program for a number of years, having replaced it with a formula that returns much more money to those counties that contribute large amounts to the coffers as a result of their far higher levels of real estate transactions.

Many of the northern counties have large amounts of public land that rarely changes hands, so the number of real estate transactions is lower than it would be otherwise. The effect is that these counties have minimal resources to allocate to projects as expensive as wall-to-wall orthophotos.

On the federal side, the National Digital Orthophoto Program (NDOP) is going through its own evolution. We are not expecting any more NAPP photography acquisitions over our state — the primary source of imagery for orthophotos in the northern counties. And, federal agency contributions to fuel the NDOP have dropped for several reasons.

First, the Farm Services Agency has begun its own summertime photography acquisition, but is not at this time planning to acquire imagery over most of the forested counties. Even if it were, the imagery would be “leaf-on”, leading to concerns over the effect of leaf cover obscuring ground features. At one- or two-meter resolution, individual trees would be hard to detect except perhaps those that stand alone or in scattered groups within otherwise unforested areas.

Second, the U.S. Geological Survey’s attentions are heavily aimed toward large metropolitan areas due to the interest in spatial information needed to support homeland security. The USGS was a critical player in achieving nation-wide coverage of digital orthophotos.

This situation leaves the northern counties with fewer options than before just at the time that federal, state, and local government budgets are under severe pressure. Their own property tax base is not large (with some exceptions for areas with high-value lakefront property), so the resources are not at hand. The sole avenue at this point might be some sort of cooperative arrangement amongst a group of interested parties, and over an area of at least several counties to attain the necessary economy of scale.