Chaparral shrubs of California.  In this mediterranean-type climate, plants must survive severe summer drought, occasional winter frost, and periodic wildfires.  As is typical for many chaparral shrubs, the Adenostoma plant shown here sprouts from the base following wildfire and other disturbance.

Mangrove trees of coastal Mexico.  These plants tolerate flooding and various degrees of salinity.  The Rhizophora mangle plants, with their famous prop roots, are particularly well suited for stability in the face of fluctuating tides.

Lianas.  These are woody vines, that is, plants that germinate and are rooted in the soil, but depend upon host plants for mechanical support.

Hemi-epiphytes.  These are plants that are epiphytic for a part of their life cycle.  However, this may be a misnomer in the case of aroids such as Monstera acuminata shown here.  This plant grows as a vine and looses stem contact with the soil only after forming aerial feeder roots.  The feeder roots provide a highly efficient connection to soil water and minerals.   

Vessels.  In this slide the narrow vessels, associated with red dye, are less prone to embolism than the wide vessels, associated with blue-green dye.  Wide vessels in general tend to be more efficient in conduction but are often more prone to embolism than narrow ones.

Woody roots.  As this excavation of Tetracera hydrophilia shows, the woody root system of lianas can be quite extensive.

Hydraulic/mechanical architecture.  The pipe model theory of plant form may be relevant to mechanical properties of trees and to issues of storage, but it is inadequate with regard to water transport issues.

Stems of climbing plants are remarkable for their variability between species.  Many climbers have anomalous secondary growth, as in the "monkey ladder plant", Bauhinia guianensis.


Deep-rooted species may have quite a different hydraulic system that shallow-rooted species.  As shown in this excavation of the liana Machaerium milleflorum, with woody roots down to 4.4 meters, many tropical plants can have deeper roots than is generally realized. 

Conductive efficiency and embolism can be measured in isolated stems with a Sperry Apparatus, shown here.


Mechanical strength of stems can be measured with an Instron.