BMW-14

Hawaiian Ethnobotany-Anatomy-14

Vascular Tissues-1

The principal functions of Vascular Tissues are the Transport of Water or Sugar throughout the plant.

The two Vascular Tissues are Phloem & Xylem.

Xylem transports Water.

It also provides the most Structural Support. This is especially true for woody plants like koa which form a lot of Secondary Xylem (a.k.a. Wood). It is the Fibers in Xylem that provide most of the structural support.

The Conducting Cells in Xylem are called Vessel Members (VM).


The Conducting Cells in Xylem are called Vessel Members. They resemble pipe sections. Water transport is facilitated by their open end walls.	Vessel Members form Vessels. These are adapted for water translocation. They also provide structural support.

Phloem transports Sugar.

The Conducting Cells in Phloem are called Sieve Tube Members (STM)

Fibers associated with Phloem provide structural support. This is especially true for plants with soft bodies like 'uala (sweet-potato).

This is a longitudinal view of Xylem and Phloem. The Sieve Tube Members (STM) are long cylindrical cells which conduct Sugar. They are analogous to the Vessel Members in Xylem & are about the same size in this case.
Vascular Bundles in ko (Sugarcane) have exceptionally large Vessel Members (VM) in their Xylem. The Sieve Tube Members are the largest cells in the Phloem.