Citation
Die Stoffbewegungen in der Pflanze (Material Movement in Plants)
TL;DR
Phloem transport is pressure-driven, not suction-driven like xylem
Münch's pressure flow hypothesis explained how phloem transports sugars bidirectionally through plants - a mechanism fundamentally different from passive xylem transport. Sugars loaded at source (leaves) create high osmotic pressure; water follows; pressure pushes sap toward sinks (roots, fruit) where sugars are unloaded.
This active, bidirectional transport model maps directly to payment networks (Stripe), supply chains requiring reverse logistics, and any system moving high-value resources that require precise routing. Understanding phloem economics explains why active transport infrastructure costs more but enables control that passive systems cannot provide.
Key Findings from Münch (1930)
- Phloem transport is pressure-driven, not suction-driven like xylem
- Flow direction determined by source-sink relationships (sugar concentration gradients)
- Active loading/unloading of sugars requires ATP (cellular energy)
- Bidirectional flow capability allows resource reallocation based on demand