Modes of failure in tubular plant organs.

PREMISE OF STUDY: Hollow tubular organs can bend and deform in one of two ways, i.e., either globally in long-wave deformation or locally in short-wave deformation (i.e., Brazier buckling). Either of these two types of behavior can cause death. Understanding the biophysical advantages and disadvantages of possessing hollow plant organs is important therefore to understanding plant ecology and avoiding damage to private or public property.
METHODS: We present computer simulations that successfully predict when a hollow organ experiences different modes of failure as a function of organ length and wall thickness as well as material properties. KEY RESULTS AND
CONCLUSIONS: When self-supporting, tubular plant organs are amenable to long-wave buckling and Brazier (short-wave) buckling under gravitational or wind-induced forces. For very slender tubes constructed of isotropic tissues, Brazier buckling depends on the outer wall radius and wall thickness (specifically Rt(2)). Particularly for organs constructed of anisotropic tissues, Brazier buckling becomes a complex phenomenon that depends on a number of geometric parameters (including length of the hollow section) as well as the material properties of tissues. This complexity precludes a definitive (canonical) limit to the relationship between wall thickness and outer radius and the safety limits for Brazier buckling.