Woodland owners now have access to two complementary and free resources on the internet to help them understand their property’s soils. One resource is the WSS (Web Soil Survey), as previously mentioned. WSS is a database of soils information for all lands in the United States. An owner can create a map of their property and a list of all the soils (see Figure 2A). WSS allows the owner to generate a table of soils and the characteristics of each soil type. A second resource is Google Earth Pro. Google Earth Pro (GEP) provides recent and historic satellite images of the Earth. GEP also includes tools that allow a woodland owner to draw and save property and stand boundaries, determine the area of mapped units, draw lines, measure distance and more. WSS also can be integrated into GEP with minimal effort.
Check out a blog about WSS and GEP. It includes several videos on how to use these resources.
A simple example of a woodlot in Tompkins County, New York, will illustrate ways to use soil information from WSS (see Figure 2B). This woodlot has four types of soils, which WSS refers to as soil map units. The two most abundant units based on the area of interest (AOI) are Erie and Langford soils. The WSS tab for “Soil Data Explorer” allows the owner to learn the site index of specific trees (see Figure 3). This example for black cherry shows that the Bath and Langford soils have a better site index than the other soils, though all are fairly good. Similarly, the soils are rated for suitability for a log landing (See Figure 4), based on slope, soil strength, wetness and potential for dust.
Another example illustrates additional information available to woodland owners. After creating the AOI, select the tab for “Soil Data Explorer” and the “Forestland” option as the manner to view soils information. Soil Data Explorer includes a tab for “Suitabilities and Limitations” and information on many subjects such as land classification and vegetative productivity. Information about the potential for windthrow is based on an assessment of the depth to a dense layer, depth to bedrock and depth to a saturated layer (see Figure 6). A visualization of the moderate vs. high ratings for potential windthrow allow the owner to modify cutting practices to reduce the exposure of trees on the more vulnerable soils.
Considering the stewardship plan, what soil characteristics should be included? The simple answer is whatever relates to the owner’s objectives. Examples of soil characteristics of potential interest to many owners include the following:
Within “Suitabilities and Limitations:”
- Soil rutting
- Potential for windthrow
- Paths and trails (look within recreational development)
- Harvest equipment operability
- Potential for seedling mortality
Within “Soil Properties and Qualities:”
- pH and cation exchange (within soil chemical)
- Available water (within soil physical)
- Drainage class (within soil qualities and features)
Finally, the tab for “Soils Report” allows owners to inspect integrated summaries of related soil characteristics. For example, information is aggregated for tree planting and harvesting because these often involve machines.
A couple of notes regarding use of WSS and GEP soils resources: first, the ratings are based on the general properties of a soil type and projected onto a specific owner’s property. Although the soil maps are usually accurate, there may be variation between the map and what the owner finds on the ground. It is prudent to spend some time in the woods to verify the maps. Second, understanding the estimates of the soil properties may require a discussion with your forester or staff at the local Soil and Water Conservation District and comparion of different parts of your property. For example, unless you know the significance of a site index of 55 versus 70, the numbers don’t mean much. Finally, a soil map unit might have a low rating for some condition, but the location of that unit might be the best option available to an owner. For example, an owner may be confronted with a wet rating for a potential log landing; however, there might be management strategies to mitigate this limitation, such as summer logging on dry ground or winter logging on frozen ground.
ForestConnect is a joint research and extension program funded by the Cornell University Agricultural Experiment Station (Hatch funds) and Cornell Cooperative Extension (Smith Lever funds) received by Cornell University College of Agriculture and Life Science from the National Institutes for Food and Agriculture (NIFA,) U.S. Department of Agriculture. Additional educational resources are available.