Related Experiment Video
Updated: Jul 19, 2026

Design and Optimization Strategies of a High-Performance Vented Box
Published on: June 9, 2023
Hydraulic design of pine needles: one-dimensional optimization for single-vein leaves
Maciej A Zwieniecki1, Howard A Stone, Andrea Leigh
1Arnold Arboretum, Harvard University, 16 Divinity Ave., Cambridge, MA 02138, USA. mzwienie@oeb.harvard.edu
Abstract:
Single-vein leaves have the simplest hydraulic design possible, yet even this linear water delivery system can be modulated to improve physiological performance. We determined the optimal distribution of transport capacity that minimizes pressure drop per given investment in xylem permeability along the needle for a given length without a change in total water delivery, or maximizes needle length for a given pressure difference between petiole and needle tip. This theory was tested by comparative analysis of the hydraulic design of three pine species that differ in the length of their needles [Pinus palustris (Engl.) Miller, approximately 50 cm; Pinus ponderosa Lawson & Lawson, approximately 20 cm and Pinus rigida Miller, approximately 5 cm]. In all three species, the distribution of hydraulic permeability was similar to that predicted by the optimum solution. The needles of P. palustris showed an almost perfect match between predicted and actual hydraulic optimum solution, providing evidence that vein design is a significant factor in the hydraulic design of pine leaves.
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