Water Off a Duck’s Back, Botanically Speaking

In the slanting afternoon sun after a passing shower and early in the mornings when the sun is low, we are dazzled by the shining beads of rain on the spicebush along the creek and the jewel weed growing thick in the wet bottom of the branch beside the house. Yesterday, this leaf-surface property of unwettability was apparent on the leaves of the Bleeding Heart beside the rock steps outside the back door.

I’ve often observed it, but never really thought much about it. What are the properties of the leaf surface that make them un-wettable and is this a random feature or does it have survival or other functional value, I finally wondered as I set about getting this image ready to post this morning.

I’m gathering resources to understand both nature’s means of beading water as well as the human-engineered nano-materials attempts to mimic nature. In addition, there is the opposite property of hyper-wettability also being exploited by industry. The end result of both properties (hydrophobic and hydrophilic) can be materials (like clothing and paints) that do not hold water, which has all kinds of microbiologic and cleanliness, odor-reduction and appearance advantages.

Off on another interesting rabbit trail–where I seem to spend so much of my time anymore, and have given up the notion that anyone else is dying to know what I found out.

Even so, it goes in my “commonplace book.” Do you know about commonplace books? No? Well, let me tell you….NAH.