Minirhizotron installation in sandy, rocky soils with minimal soil disturbance

We developed and demonstrated the utility of a technique for installing min irhizotron tubes in sandy, rocky soils where more traditional installation methods are inadequate. The method uses a pneumatic rock-drill alternately to drill and drive drill casing into the soil. Soil particles and drilling debris are removed from the casing as it is installed. The minirhizotron tu be is inserted into the drill casing and the casing is withdrawn. A pneumat ic screw-drive guide system powers the downward and upward movement of the rock-drill and controls the angle of installation. Working from a platform suspended from a center-pivot elevated catwalk minimized soil disturbance. Soil contact and root ingrowth around the minirhizotron tubes were very sat isfactory. This method, while fairly labor intensive, allows minirhizotron studies of root dynamics in sandy, rocky soils where they would otherwise n ut be possible. Also, there is much less soil compaction and disturbance th an traditional installation techniques entail.