Soil Analysis

Below is a spreadsheet with data points from four sites around FeF.

The main block we are encountering as far as producing CEBs from all onsite resources is sharp sand. As I walked the property looking for sand, I wondered if it could be somewhere on site. we have a main creek running through the forest, so I figured all the sand would be at the very bottom of the slope where it meets the street. I found only clay and silt, but very dark and nutrient rich soil here. I assume the nutrients are washing fast down the slope due to the extreme erosion at FeF.

My next idea was that it would be found in the upper slopes where there are keylines (places where the slope graduates into wider contour lines). There, I found very pure sand; all the clay and silt had washed down slope and left very sharp sand mixed with organic matter.

So I am wondering now, how far down does the sand go in these spots? Are there other places where we can harvest without cutting down trees? There are many ruts around that must be collecting sand. If not, where would be a good site in the forested creek belt where a pond would be appropriate and non destructive?