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2. Soil Fundamentals
Supplies
•
Clear plastic or glass jar(s) filled with irrigation water
•
Wire mesh (hardware cloth) or window screen formed into a basket to suspend
from the rim of the jar, with its bottom about 2 inches into the water
•
A small shovel or other tool for collecting your sample
Instructions
1.
Collect several soil clods or aggregates and air dry them for at least 1 week. Depending
on initial moisture and soil texture, drying may take up to 1 month.
•
You may want to collect clods or aggregates from various soil types or soils
under differing management regimes to compare them.
2.
Set up jars with your irrigation water.
•
Note that the use of irrigation water differs from the NRCS protocol, which calls for
distilled water. Using irrigation water will give a better idea of how the soil will behave
when irrigated. If you don’t have irrigation water available, distilled water is fine. Be sure to
record what kind of water you have used.
3.
Place one or more soil clods or aggregates
into the wire basket in each of your jars.
Make sure they are fully submerged.
4.
Observe the soil clods or aggregates over
the next five mnutes - what percent of
the clod remains intact?
Interpretation
What was the topography like from where
you collected the sample? What was the soil
depth?
What was the vegetation in that area?
What has the management been in that area?
These are just some examples of things to
think about, observe, and compare. Based on
what you know about your property, can you
come up with some of your own?
What did you observe?
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Activity – Water Stable Aggregate Test (Slake Test)