Field Soil Tests

We just collected soil from 4 different areas on the property that appear to be different types. 1 was over 5 times slower to drain, highest in clay, and darkest brown looking. 1 was the fastest to drain and seemed to have sand. It would hardly hold it's shape when squeezed. The other 2 were halfway between the other 2 extremes except one was a very bright red and the other more of a brown. Weird. Below are the various tests were performed on the soil samples:

1. Drainage test: using a post hole digger, dig 1 ft deep hole, fill with water and allow to drain completely. Immediately refil and measure depth of water. Wait 15 minutes and measure again how much it's dropped. Multiple this # by 4 and this is "/hour drainage rate. < 1"/hr is poor (clay) drainage. 1"-6"/hr is desirable. >6" excessive (sandy) drainage.
2. Root test: dig into soil near an established plant. Look for fine hairy roots (not just coarse roots which indicate poor drainage) going deep with no sharp turns (hard pan)
3. Smell test: good earthy smell indicates good biological activity. Some people even taste. If sour, it's acidic, if bitter, it's alkaline, if sweet, that's good.

4. Ribbon test: this is to test soil texture. Take a handful of soil (not too dry, not too moist) and squeeze. If it won't stick together at all, it's sandy. If you can stick it together in a rod shape, 1" in diameter much longer than 1" in length w/o it breaking up w/o support, it's clay. In between the two is loam.

5. Topsoil Depth Test: Observe where the color changes in the soil. < 6" is not good. The above picture is of a soil probe which is also great for collecting 8" deep samples to send to the lab for pH and mineral composition testing.
6. Bedrock / Hardpand Test: take a rod with a sharp end (like what you stake tomatoes with) and poke into soil to max depth able to by hand. Test in several spots to account for individual smaller rocks that may be in the way.
7. Earthworm Test: If soil is somewhat warn, and somewhat moist, dig out top 6" of 1 foot square. >10 is very biologically active soil, 3-10 is good but could be better. < 3 is not very biologically active.