Commissioned by a company called Decagon Devices, Inc. (a company which designs and manufactures a variety of sensory devices for agricultural, industrial and research uses), this illustration shows the 5TE Soil Sensor.  It was included as part of the manual for the 5TE.

Also part of the 5TE manual, this illustration and the following illustration show correct installation techniques for the sensor.  Both include the data logger.

While not technically a technical drawing, this illustration was also commissioned by Decagon as a Christmas card.

The first installment in a series of illustrations, this figure was commissioned by an agricultural outreach program for a book designed to help landowners understand soil health and the management thereof.

This illustration shows the interaction of a specific kind of fungus with the roots of a White Pine.