These compounds form a thin, clear polymer film over the stomata on the leaf surface, physically blocking moisture vapor from escaping. Growers use them primarily on newly transplanted trees, cuttings, or evergreens facing harsh winter winds to prevent desiccation. While they conserve internal moisture, they also temporarily reduce photosynthesis by restricting carbon dioxide intake.
Heard on the job
Spray the bare-root pines with an antitranspirant before we load them on the truck so they don't dry out in transit.