Forestry

Aerial Photography

Frequently Asked Questions

Below are the questions most frequently heard from people filling out the order form. Do you have any questions that you don't see here? Email them, or call us at 608-266-2050.

What is a legal description?

The legal description of a piece of land is the generic term for the township, range and section numbers (explained in the next section). The legal description can be used to order contact prints or digital scans (if you are ordering fewer than nine prints or scans). You cannot use the legal description to order enlargements. A legal description might look like this: "T9N R10E S6". View more information, including a tutorial.

What do the township, range and section numbers mean?

These letters and numbers make up the legal description of piece of property. The state of Wisconsin is divided into a grid according to the PLSS, or Public Land Survey System. Each of the grid squares measures approximately 6 miles by 6 miles. These areas are identified by a north-south number (township) and an east-west number (range). These two numbers tell you approximately where in the state the land is located. Each of the six-square-mile areas is further divided into 36 numbered sections, each of which is approximately 1 square mile. For example, "T9N R10E S6" means "township 8 north, range 10 east, section 6". View more information, including a tutorial.

When "township" is asked for on an order form, the number as described above should be entered, NOT the name of the township (i.e., "T9N" rather than "Sun Prairie").

Where do I find the township, range and section numbers of the land in which I'm interested?

One of the most easily accessible places to locate this information is in the "Wisconsin Atlas & Gazetteer" by the DeLORME Mapping Company. It's available from many bookstores, gas stations and discount stores.

Plat books contain this information as well. Plat books can be purchased, or contact your county clerk or local library.

How do I know if my county is available as black-and-white IR or CIR?

Forestry’s Aerial Photography Project is in the process of converting from B&W IR to CIR.  Each county is available in only one format depending on the year of acquisition. Refer to the map to determine whether the county you are interested in is available in B&W IR or CIR.

Can I order an enlargement, and how do I know that I'm ordering the correct picture and cropping?

Yes, custom orders may be purchased from HAS Images, Inc. [exit DNR] Please contact HAS Images, Inc. directly for more information on ordering enlargements, transparencies, and custom scanning products.

To ensure that you order the correct picture and cropping, you first need to determine the actual photo on which the land is located. The best way to begin this process is by consulting a photo index map. Once you know the flight line, roll number and frame number of the photo, you can then visit the forestry field office where your land is located to view their copy of the contact print, or order a proof print of the photo.

Once you see either a copy of the contact print or the proof print, you can then decide which cropping option, or sectional, you need in order to get the desired area enlarged. The sectionals are explained in the Enlargement Print Ordering Details section.

Before ordering an enlargement, you should always view the original or proof print from which you plan to order. Because the photos do NOT follow the township and range lines but rather the the plane's flight lines, it is extremely difficult to determine which photo and which sectional option will give you the desired enlargement unless you view the photos beforehand.

What is a photo index map, and where can I get one?

Photo index maps are created for the DNR after the airphoto flights are completed. The maps have the flight lines in which the planes flew, the number of the roll of film they were using for each flight line, and the area of land covered in each photo frame. This information can then be used by you to determine which photos you might consider purchasing.

If you are ordering fewer than nine contact prints, then you do NOT need to use a photo index map. You can place your order using the legal description. If you are ordering 10 or more, you will need to refer to a county index map.

For example, if you know that you want to order an enlargement of a piece of land in Dane County with the legal description of "T9N R10E S6", you would look at the photo index map for Dane County, locate the area by legal description, and then see which flight line, roll number and frame number appears to contain your land. You would then visit the Forestry field office where the land is located to view a copy of the print, or you would order a proof print to be sure that you have identified the correct photo. By looking at the contact or proof print, you can see if all the land in question is contained on the photo. If it is, then you can determine which sectional (explained here) would give you the best enlargement. If it's not, then you might need to look at other contact prints or purchase another proof print before ordering your photo.

Photo index maps are available from the Wisconsin DNR. To view an index map, visit the Forestry field office of the land's county in which you are interested. Each office has the index maps for ONLY their county. Or, you may visit the Division of Forestry's Central Office at 101 S. Webster Street in Madison, where you may view the index maps for any county in the state. Please call the offices before visiting to ensure that someone is available to assist you.

Last Revised: Friday December 12 2008