How to use soil surveys and aerials photos in logging
This web article explains
how loggers, landowners, and foresters can use soil surveys and
aerials photos to plan a timber harvest.
A soil survey is a map and booklet that describes the location
and expanse of different soil types in New York. "Know your
soil" is an important term to keep in mind because the soil
type controls many aspects of forest health. They indicate different
soil types and names, wet spots, drainage patterns, steep slopes,
and other good information. Remember, forests do not exist without
The quality of the
soil affects what kinds of trees will grow and how well they can
tolerate windstorms, wetness, and regeneration. For forest management,
a soil survey provides a description of the suitability of the
site for logging roads, reforestation, and typical forest types.
To obtain a county
soil survey, stop by the local Soil and Water Conservation District
or Cornell Cooperative Extension office. You can get a copy of
the information or purchase the entire survey. Some offices will
provide you with a soil survey at no charge. If you are not familiar
with soil surveys or how to use the information they have, talk
to a Soil and Water Conservation District technician or county
Cornell Cooperative Extension educator.
a soil survey, locate the timber harvest site using the locator
map and map numbers. Use your knowledge of roadways and streams
to pinpoint the exact location of the timber harvest site. Read
and make a note of which soil survey symbols correspond to all
areas of the site (VoB, Ar, CaB, etc.). At the beginning of the
map section, there will be a chart that matches the soil symbol
to the name of the soil. Write down the names and locations of
these soils on your baseline map, outlining their general location.
In the text portion
of the soil survey, you will find a complete description of the
soil and its quality. The description will explain whether it
is well-drained, whether it is especially wet during the spring,
and its limitations for reforestation, farming, and other activities.
Other charts in the soil survey summarize the soil properties
for forest roads, erosion potential, and tendency for compaction.
All this information leads to a much better understanding of the
erosion potential of the harvest site.
photographs will help you get a bird's eye view of your forest.
With it, you will see features you've not seen before. Many county
Soil and Water Conservation District offices keep good aerial
photographs on hand and will copy one or two for you for a small
fee. It is worth every penny. Get a lot of copies so you can mark
them up with all your forest plans! Satellite imagery is available
on-line, but the low resolution is frustrating to work with, unless
you have a massive forest. Instead, get the aerial photographs.
If you go online, look at the NYS Geographic Information Systems
Clearinghouse at www.nysgis.state.ny.us.
How to use aerial
photos and soil surveys to plan a timber harvest
|Click on the image to see
what information can come from an aerial photograph.
Identify and understand
the soil types and slopes in the proposed timber harvest site.
areas based on soil drainage, so work can be done on firm ground
to extend the work season and ensure a timely harvest schedule.
You can estimate slopes with the following conversion table:
| ErA = Erie silt
loam, 0 - 3% slopes (gentle slope)
| EuB = Burdett
silt loam, 3 - 8% slopes (moderate slope)
| LnC = Lansing
gravelly silt loam, 8 - 15% slopes (somewhat steep)
| HnD = Hornell
channery silt loam, 15 - 25% slopes (steep)
| SyE = Schuyler
silt loam, 25 - 35% slopes (very steep)
These slopes and soil types can
identify soils that are well-drained, suitable for skidding even
during wet seasons.
Identify seeps and
wet spots in vicinity of logging.
These areas are marked with a special symbol or dashed line. Forested
wetlands should be avoided as much as possible when harvesting
starts. Soil surveys note where seeps, springs, and wet spots
may interfere with good logging conditions. There are critical
areas and should be avoided. Normally the soil in these spots
will never dry or freeze. Logging equipment is likely to cause
significant erosion in wet areas.
Small-scale or intermittent streams may be dry through most of
the year, but have flowing water after storms, heavy rain, or
during spring runoff. Timber harvesting operations should work
around or cleanly over these streams, protecting the banks from
in woodland types.
often help clarify where forests change composition. For example,
a pine-dominated forest will appear darker than a hardwood forest.
Subtle changes, such as from a young aspen stand to an older maple
stand can be identified with aerial photographs.
roads, pipelines, and jeep trails may be visible on soil survey
maps. If these are properly constructed, they can be used for
logging equipment movement without harming forest soils. These
existing roads can also provide options for entering the property.
See property features
on adjacent land.
harvest planning takes into account water features on adjacent
property, such as small wetlands, streams, and farm ponds. Use
aerial photographs to avoid the mistake of polluting water bodies
within a short distance of the timber harvest. Aerial photos will
also show current woodland edges, streams, sapling stands, softwood
plantations, and adjacent property features.
Forest owners, loggers,
and foresters are all responsible for ensuring logging activities
do not cause environmental harm to streams and lake waters.