Soil boring and sampling is a process that sampling technicians use to collect soil samples for analysis. The federal and state environmental and agricultural departments establish guidelines for creating soil borings and collecting soil samples. These guidelines help to ensure that you collect representative samples of the area soil and that no outside contaminants affect the samples during the collection process.
The Purpose of a Soil Boring
Soil boring is the process of using a hand tool or drill rig to collect a soil sample from below the surface of the land. The resulting hole in the subsurface is also called a soil boring. By creating a soil boring, you can collect representative soil samples from below ground.
The depth of a soil boring is limited only by the ability of the tool that you use to create the hole. For example, a hand auger relies on the strength of the operator to advance the tool and cannot go as deep as a mechanical drill rig that uses engine power to advance the augers.
The depth of the sample that you are trying to obtain will dictate the type of tool that you should use. For garden sampling, shovels or hand augers are the best tools for sampling because you generally need to sample only as deep as the root zone of the plants in the garden.
How to Create a Soil Boring
To create a soil boring, you must start with a clean boring tool such as a shovel or stainless steel hand auger. Clean the instrument with rubbing alcohol and rinse with water to remove debris and oils. A soil boring is a hole dug vertically into the ground that is generally deeper than it is wide. Insert the shovel or twist the hand auger into the ground to make the boring. As you dig the soil boring, place soil that you remove but do not plan to sample onto a sheet of plastic. After you complete the boring and collect your soil samples, you can replace the soil in the borehole.
Types of Soil Samples for Homeowners
Homeowners often test the soil in their property to ensure that the soil has the proper pH and nutrients to sustain garden and landscape plants. Soils tests that determine the composition of the soil are also beneficial because they can tell you if the soil has adequate amounts of sand, silt, clay and organic matter to help plants grow or if you need to amend the soil so that conditions are more favorable.
You can collect both discreet and composite soil samples from your property and submit them for analysis at agricultural or environmental laboratories. Discreet soil samples are from a single location while composite soil samples are from multiple locations that you mix together. If your plants require the same pH and nutrient amounts, you can use a composite sample of several locations around your property to reduce the overall cost of the sample analysis. If your plants have different requirements, use discreet sampling from each area for specific information.
How to Collect a Soil Sample
As you create a soil boring, place the soil that you wish to sample into a clean bowl until you have enough soil to fill a sample jar. Ask the laboratory that you plan to use to send you sample bottles or ask them what type of container you should use. As you place the soil into the sampling bowl, remove large rocks, twigs and leaves. Mix the soil in the bowl with a clean spoon and place it in the sample jar. Most sample jars have labels to fill out with your contact information. The laboratory may also ask you to fill out a chain of custody form that lists the analysis that you want for each soil sample.