Light micrograph of a cross-section of a blade of Marram grass (Ammophila arenaria, formerly Psamma arenaria). This grass is wide.ly planted to stabilise sand dunes as it is resistant to desiccation by the wind. This resistance is due to its tough waxy outer epidermis with few stomata and an elaborate inner epidermis covered with fine hairs designed to collect and retain moisture. The leaf can roll up completely to retain moisture. Magnification: x68 at 10cm wide.