It is not possible to perform girdling experiments in monocots. In monocots, the vascular bundles are scattered in the ground tissue. Therefore, continuity of vascular tissue is not disturbed hy removing the outer layers. Girdling is usually done in woody stems of dicots, where collateral vascular bundles are arranged in one ring. In such stems it is possible to remove all the tissues outer to vascular cambium (bark, cortex and phloem).