Soil Probe

Cadaver / Victim Recovery / Body Dogs / Human Remain Detection section

Soil Probe

Postby Daryl » Fri Aug 07, 2009 7:19 pm

There was some discussion over the use of a soil probe in another topic, so thought I would add to the debate.

Cadaver Dog Handbook wrote:SOIL PROBE
The dog’s ability to pinpoint a buried body depends upon air exchange from below the soil surface. Certain soils, especially those with tight composition, may not allow much scent to reach the surface. Occasionally the handler will observe the dog working an area intently, but without being able to indicate an exact location. Another situation may arise with a burial on a slope, where the alert occurs at the bottom. In both of those situations, in order to locate the scent
origin, the soil must be vented.

Soil in a suspected area can be vented with a soil probe, increasing air exchange and releasing additional scent. Changes in underground density (suggesting disturbed areas) may also be felt by the operator. These items (see Appendix A) can be purchased or made by a welder. The probe is inserted into the soil at regular intervals where the dog will be directed, or at an especially promising location.

The area to be vented should be well delineated. Start with one boundary and probe as deeply as possible approximately every 18 inches. After finishing line one, start a second line of holes offset from the first. Continue this technique until the entire area has been covered. As you proceed, you will become accustomed to the normal resistance in undisturbed soil. If using a core sampler probe, check initial samples from undisturbed areas to establish the normal types and depths of the various strata.

If you locate an area that has been disturbed, the probe will penetrate with less resistence. It is possible to determine the dimensions of the distrubed area with the probe. If using the core sampler , you will notice the strata are not defined, since the soil layers are intermixed when the area is refilled. You should then be able to locate the walls of the excavation. If a disturbed area, mound, or depression contains a body, you may detect decomposition odor on the soil that adheres when the probe is removed from the soil.

Use caution when probing a disturbed area! The probe can cause postmortem injury to the body or bones.

Once an area has been vented, let it rest a while—at least one-half hour—for scent to become available. This will clear the area of the scent of the workers and allow a more efficient search. Then work the dog in a tight grid, quartering the wind, to locate the area with the strongest scent. Check all disturbed areas carefully. Be careful not to “talk” your dog into a false alert.


We have used other, similar techniques for attempting to pinpoint a scent source, especially with older graves.

A post hole digger can be used easily in softer loam or sandy soils. Holes are spaced approximately two feet apart and a minimum of two feet deep. This method works well, especially if you are trying to locate a source on a hillside. In this situation, the dog will indicate on the holes below the source, but should give no reaction when searching above the source.

Trenches can be dug laterally on a hillside to attempt to find the source. They can be dug either with a shovel or backhoe. The depth is dictated by the type of soil and plant growth.
Daryl Toogood
Berkshire Search & Rescue Dogs

"I can explain it in Dog, but you only listen in Human."
-- Gaspode the wonder dog
Posts: 2624
Joined: Sat Feb 09, 2008 12:42 am
Location: Berkshire

Re: Soil Probe

Postby jicarrie » Sat Oct 15, 2011 12:50 pm

We use a variety of soil probes for our searches. These include long thin ones, hollow probes and small heavy duty pointed ones.
I've attached a photo and will look for some of the others. We get them custom made by one of our team members.

Hope that helps [laugh]

Hollow probe
User avatar
Posts: 4
Joined: Sat Oct 15, 2011 11:56 am
Location: Llanrwst, Conwy County, North Wales, UK

Return to Cadaver

Who is online

Users browsing this forum: No registered users and 1 guest