I am on a botany kick lately, so if you, my dear reader, cannot handle the plant nerdiness, check back next week. But I caution you – this is one for the ages!
One of the things I love about the world around us is the endless fascination to be found no matter the scale, a single cell or a whole garden view. To train, to hone one’s observation skills pays off in a lifetime of endless wonder.
Some parts of nature are less appetizing to the wonder bug in most of us. Some plants seem tough on the outside like a Hell’s Angel, but are a big goofy, puff ball of great secrets and cool stuff under the surface, literally.
Sometimes when I need time to myself, I like to pick up The Big, Bad Book of Botany by Michael Largo. It is often a fascinating look at some very nasty plants. One in particular, Cnidoscolus angustidens, is a member of a plant family with long ties to many different cultures: Urticaceae, or stinging nettle family. Other fascinating members of this large family include Pilea microphylla, artillery plant, known to explosively shoot pollen from male flowers and our plain old annoying, everyone loves to hate local species Urtica dioica.

Common stinging nettle grows absolutely everywhere (including north of Alaska!), so good luck removing it from your backyard. Just saying. What I find so fascinating about this species is its mode of attack. This Hell’s Angel may have a bite, but deep inside is some really good stuff if only you take time to connect with it (not by tactile means, of course). One of the reasons Urtica dioica grows particularly well at Wellfield is due to its love of silica based soils, i.e.-sand. It utilizes this silica in its defense system. If you look closely at the plant, not too close mind you, one will see tons of hollow stinging “hairs” or cystoliths on the underside of the leaves. Here’s a nice macro photo of cystoliths:

These hairs are where it is at for this botanist. They are present across the family, are not always filled with a stinging concoction, but are usually mineral-reinforced. Our common nettle’s hair is a single elongated cell with a swollen base which contains a swirling cocktail blend of chemicals meant to swell the skin (histamine) and fire off the nervous system (serotonin, et al). “Nettle” comes from the Anglo-Saxon word naedl, meaning “needle,” an appropriate label if you look at a picture of these cystoliths. Made of silica (a.k.a. glass), the very small glass needle is capped at the tip by small bulb which breaks off upon contact, creating a very sharp point (nice to know eh?). This swirling mixture of joy is under pressure, and the motion of contact compresses the bulb to squeeze out the surprise party awaiting thine epidermis. I would also note, the cystoliths grow in a certain direction (upwards upon the stem and downwards upon the leaf) which if rubbed in the direction of growth prevents hours of fun. Now is that cool or what? You just got hit up with a tiny doctor’s needle right there in the woods.
But wait – there is more coolness coming! Many cultures believed that such hard-to-get-to-know-you plants were off-putting because they were stingy on sharing the secret benefits contained inside; Urtica contains many wonderful vitamins and minerals.
What else? Well, many early civilizations used the stinging nettle to alleviate pain from arthritis and rheumatism, and before hemp’s textile properties were discovered, the strong mineral reinforced stem fibers to make garments soft as silk (according to Michael Largo). Yes, from painful to healthy, from ouch to silk, we have covered it all in just one family. Not so impressed? Not interested in close encounters of the Urtica kind? I don’t blame you, but these plants are so bad they’re cool. Well, enough of the stinging remarks, tune in again next time for more fascinating botanical facts!
Josh Steffen
Horticulture Manager