Volumetric Aggregate Stability Test:
Monitoring Physical Properties of Soil


VAST – A New Test for Water Stable Aggregates

Soil Labs already performing parts of soil health analyses now have the opportunity to include a cost-effective test for water stable aggregates. VAST stands for Volumetric Aggregate Stability Test and is a rapid, commercialable procedure.



What are Water Stable Aggregates?

Water stable aggregates which may form in soil are responsible for very important properties such as erosion resistance, gas diffusion and water infiltration. The loss of these physical properties through soil destructive events can turn a great soil into a problem soil of low productivity.  While it is generally known that intensive management and insufficient return of organic residues to soils affects water stable aggregates unfavorably, farmers have not been able to monitor these changes since traditional research methods for aggregates are just not practical in the commercial soil lab.

How does it work?

Woods End’s new lab procedure VAST revolutionizes the analysis of stable aggregates to become simpler and more cost-effective. The new approach was made possible by integrating the quantitation of aggregates with a structural geometry model instead of the traditional gravimetric approach. The latter requires several careful steps of drying and weighing conducted over a period days. VAST makes it practical to perform the test in a single, two-tiered wet process, eliminating steps of drying and weighing. The results of VAST do correspond to traditional lab slaking methods. VAST presents an interesting and new line of inquiry about the best means to represent soil aggregates which ultimately volumize soil, reducing its relative bulk-density at the same time as producing many desired traits.

VAST is not an automated protocol, and requires an operator to be trained to properly conduct the procedure. Woods End new commercial offer to Solvita labs includes the equipment and training in an exciting and affordable licensing process.  Labs may have to make certain operational changes, including modification of how soils are prepared and ground (milled) before testing to reduce artifacts. It is also expected that labs will incorporate VAST into soil health regimens for the benefit of customers.


Volumetric Aggregate Stability Test

Volumetric Aggregate Stability Testfing Products