Scanning electron micrographs (SEMs) of soil in furrows treated with irrigation water containing PAM were made in this same field (Courtesy Craig Ross, Landcare New Zealand).  The SEMs show the untreated soil particles on the left, and the PAM-treated soil particles on the right.  The left image shows a diatomaceous "skeleton" from algae in the irrigation water.  The PAM applied via the irrigation water to soil (in the image at the right) is the netlike material covering the soil particles; this image provides a clear look at how PAM holds soil in place in treated furrows.  These images are from an area just below the furrow inflow point and, in the case of the PAM-treated furrow, would represent a higher than average PAM coverage than would be expected in the lower reaches of the furrow.