Side Pruner Developed at Mount Shasta Nursery
We will discuss briefly the experiments conducted in developing this root-pruning machine.' Work on the machine was started a few years ago. Trials made last year were most encouraging, so we built a side pruner based on those tests. It was difficult to find cutters that make a clean cut without tearing off the roots. However, cutters like those shown in figure 1 proved almost completely satisfactory. These cutters, which are self-sharpening, were made from 20-inch coulters.
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Author(s): Karl B. Landquist
Publication: Tree Planters' Notes - Issue 70 (1965)