The information presented in this article is an excerpt from the newly revised publication Land Survey & Mapping: An Introduction for Woodland Owners (PNW 581) (By Norma Kline & Alicia Christiansen, April 2020). Download & read it here: https://catalog.extension.oregonstate.edu/pnw581

As a forestland owner, you likely have dabbled with using digital mapping technology to help manage your property. You may have downloaded county tax lot maps, used Google Earth to look at an aerial photo of your forest, or explored Web Soil Survey to understand the soils on your property. Advances in digital mapping technology have increased the types of available map data and the way users interact with maps. Read on to learn more about useful digital mapping resources for forestland owners.

Why use digital maps?

Digital maps have a tremendous range in capabilities including:

• Static maps you can view, print or download.
• Searchable maps with data.
• Map interfaces with digital drawing or measuring tools.

Web-based resources offer free, easy access to high-quality aerial photographs and geographic data. The functions and capabilities of digital maps vary by site. Some sites have tools for mapping and simple geographic measurements and analyses. Other sites are repositories or libraries for digital maps and data. It is a good practice to take a look at the source of the data, the date it was created and the general accuracy or precision of the data.

Commonly used digital maps and websites

Digital map resources include aerial imagery, tax lots, roads, boundaries of counties and government land ownerships, topographic maps, LiDAR, soils and vegetation cover. Historical maps are a great resource to find old place names, locations of homesteads and other historical features. In addition to USGS map sources, scanned historical maps are often available in university digital archives.

Google Earth

Google Earth is a web-based geographic browser that accesses satellite and aerial imagery to produce a 3D interactive globe. It is available for free for both basic and advanced versions. Google Earth allows the user to search for specific addresses or coordinates and see points of interest from various angles. The program has many functions that allow the user to learn about specific places of interest. These “layers” can include photo and video, allowing the user to interact with various recorded locations.

Web Soil Survey

The online Web Soil Survey, produced by the National Cooperative Soil Survey and operated by the USDA Natural Resources Conservation Service, allows you to view soil data and associated information. Soil surveys provide users with information on soil type, properties, qualities and limitations for use. Users can use downloaded soil reports as references for land management activities.

County tax lots

County tax lot maps are useful for mapping, property analysis and planning purposes. Some counties have map viewer applications for viewing tax lot information, plats and additional county planning data. Investigate your county tax assessor site to see what digital map resources your county provides. For specific information regarding individual tax lots, contact your county assessor.

 Digital libraries and data sets

Digital libraries and data sets are compilations of digital map data for a specific region or theme. These sites often provide a variety of additional features, including map viewer applications that allow you to take simple measurements and view multiple layers and linked resource data. Examples include Oregon Explorer, Atlas of the Pacific Northwest, Inside Idaho, Washington Geospatial Open Data, USGS National Map Viewer, USGS TopoView and CalTopo. The National Geographic Trail Maps website has downloadable USGS 7.5-minute topo maps that can be printed out to scale on four letter-size (8.5-by-11-inch) sheets of paper. The CalTopo website allows you to select mapping layers and download the file as a georeferenced PDF that can then be uploaded to mapping apps for use offline in the field.

Ecotrust Forest Planner

Ecotrust Forest Planner is a web-based tool used for forest management and scenario planning for landowners in Oregon and Washington. This tool provides a variety of resource layers and tools to help landowners explore forest management alternatives.

Geographic Information System

A Geographic Information System links information collected about the earth’s features and resources to a digital base map. Information on each type of resource is stored as a mapping layer, like layers of acetate laid over one another. Resource layers commonly include the Public Land Survey System, topography, transportation, water, vegetation, geology and land ownership. Digital aerial photographs are also commonly used in a GIS. The layering of different features allows for complex analyses and modeling as well as detailed, efficient mapmaking.

GIS is generally used by owners of large properties, but some small woodland owners find it useful. However, commercially available programs with a licensing fee might be out of reach for small woodland owners. You might consider a variety of free applications now available.

 Apps

Several apps are available for users to download onto mobile devices, such as smartphones and tablets. A user will interact with these apps to accomplish a task in the field, such as mapping a property boundary, inventorying a stand of trees, inputting data, referencing data or georeferencing photos. Not all apps are free. Prices vary, so be sure to read the fine print regarding subscription services or any extra costs for downloading maps or data.

All smartphones and tablets have a basic map app preloaded onto the device. Most of these basic map apps, such as Google Maps, perform basic functions such as navigation and saving points of interest. For a more detailed map experience, an app such as Avenza Maps can be downloaded. This app allows the user to download maps for offline use (no cell service required), use the device’s built-in GPS to track your location on any map, plot locations and photos, measure distance and area, and more.

To perform a forest inventory, an app such as Plot Hound can be useful. This app allows the user to download cruises and plots to their device, navigate to each plot with their phone’s built-in GPS and compass, and enter data collected in the field.

For soils information, an app such as SoilWeb can be a great tool. This app is based on the USDA’s National Cooperative Soil Survey and provides GPS-based soil information for your current location. This app can be used in the field where cell coverage is available to better understand the soil types and how to optimally use the soil.