Girdling and tree death: lessons fromChamaecyparis pisifera

Abstract

To investigate the effects of girdling on the water relation of trees, we measured a number of water-status parameters and morphological features following trunk and branch girdling of Chamaecyparis pisifera Siebold & Zucc. Girdling caused a marked reduction in the water-conduction area of the trunk cross section at the girdled part. Some girdled trees generated intense acoustic emissions (AE), simultaneously decreased leaf water potentials (LWP), and then died within 1 year. However, others lived for more than 2 years after girdling. In these survivors, the water-conduction area of the trunk cross section was reduced but not entirely blocked, and LWP decreases did not occur. Consequently, we conclude that girdling affects xylem water conductivity and sometimes causes short-term (within 1 year) tree death by blocking water uptake from soil to leaves. The results of this study on whether tree death from girdling occurs sooner or later could be important in the use of girdling for thinning management.