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How do vessel members transport water in flowering trees?

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temperate softwoods and hardwoods selected to show variations — wood Temperate softwoods (left column) and hardwoods (right column), selected to highlight natural variations in colour and figure: (A) Douglas fir, (B) sugar pine, (C) redwood, (D) white oak, (E) American sycamore, and (F) black cherry. Each image shows (from left to right) transverse, radial, and tangential surfaces. Click on an individual image for an enlarged view.

In flowering trees, water is transported through specialized xylem structures known as vessels. These vessels are formed by a vertical series of dead, hollow cells called vessel members that are arranged end-to-end to create long, capillary-like tubes.123

During their development, the end walls of these cells dissolve to form perforations, and the living contents of the cells disappear, leaving an unobstructed pathway for water to flow. The upward movement of water through these tubes is primarily driven by transpiration pull, a process where water evaporates from the leaves, creating a gradient of decreasing pressure that pulls water from the roots to the crown.12345

This mechanism relies on the cohesion hypothesis, which states that water molecules hold together through cohesion and adhere to the vessel walls, allowing the water column to withstand the high tensions required to reach the tops of tall trees without breaking.45