Girdling is removing the bark and phloem tissue from a stem. The stem remains alive because water and nutrients can still travel in the xylem. This treatment is used in propagation because it can halt the downward flow of auxin, so it accumulates at the site of girdling.
Girdling a stock plant can result in improved rooting of stems taken from girdled plants; girdled stems from stool beds; and during air layering.
