Which statement correctly describes leaf features that prevent spray droplets from adhering?

Which statement correctly describes leaf features that prevent spray droplets from adhering?

• A. Waxiness (CUTICLE)
• B. Hairiness (PUBESCENCE)
• C. Both waxiness and hairiness
• D. Neither waxiness nor hairiness

Answer: (C)

Droplet adhesion on leaves is reduced when the surface is both hydrophobic and rough. The waxy cuticle makes the leaf surface low in surface energy, so water-based spray droplets tend to bead up rather than spread, making them easier to shed. Hairiness, or pubescence, adds micro-roughness and can trap air between the droplet and the leaf, further lowering wetting and increasing the contact angle. With both features present, droplets are less likely to wet the surface, and gravity or wind can more easily push them off. So, having waxiness to reduce energy and hairiness to disrupt wetting together provides the strongest anti-adhesion effect, which is why both features describe leaf traits that prevent spray droplets from adhering.

Droplet adhesion on leaves is reduced when the surface is both hydrophobic and rough. The waxy cuticle makes the leaf surface low in surface energy, so water-based spray droplets tend to bead up rather than spread, making them easier to shed. Hairiness, or pubescence, adds micro-roughness and can trap air between the droplet and the leaf, further lowering wetting and increasing the contact angle. With both features present, droplets are less likely to wet the surface, and gravity or wind can more easily push them off.

So, having waxiness to reduce energy and hairiness to disrupt wetting together provides the strongest anti-adhesion effect, which is why both features describe leaf traits that prevent spray droplets from adhering.