The many uses - both good and bad - of stinging nettles

You're out for a walk in the woods, enjoying a stroll along the river.

Then, suddenly, you feel as if you've been stung by a thousand sharp needles. Your arms and legs start to burn and itch. You scratch frantically. You want to jump in the river for relief. Sound familiar?

Welcome to the world of stinging nettles.

Stinging nettles are plants that thrive in floodplains forests. They're worth getting to know, and better on your terms than on theirs. If you don't know how to identify nettles, all it takes is one encounter and you will soon become an expert in nettle identification.

Nettles are tall, green plants that are in their prime from midsummer to fall. Their outstanding feature is that there are no outstanding features. The leaves are just, well, green. They're lance-shaped or widely oval (depending on the species), with toothed edges. The flowers are small, green and inconspicuous. Most notably - take a close but cautious look - the entire plant is covered with sharp little hairs. Herein lies the challenge.

Each slender hair acts like a hypodermic needle. If you brush ever-so-slightly against a nettle plant, thousands of these little needles will inject a mixture of formic acid (the same chemical that causes bee stings to hurt), histamine, and acetylcholine. This chemical warfare has effectively deterred herbivores of all shapes and sizes throughout the ages.

There are several types of nettles that sting. One species is the native wood nettle (Laportea canadensis). The other is commonly known as stinging nettle (Urtica), which some taxonomists have lumped and split in different varieties.

Urtica originated in Europe, but it's been in North America long enough to be incorporated in Native American ethnobotany.

You'd think no one would be even tempted to mess with these plants, but they've been utilized in both the Old World and the New World for centuries. Driven by hunger or curiosity, or both, people discovered long ago how to remove the stinging hairs from nettle.

They learned that a quick douse in boiling water does the trick. Once disarmed, nettles were found to be very nutritious, full of medicinal properties, and a great source of fiber for rope-making.

Nettles are full of nutrients, on par with spinach. The leaves contain high levels of vitamins C, A, and D, plus manganese, iron, calcium and potassium.

"The tender, pale green top leaves are excellent simmered in just enough water to cover and served with butter and lemon," wrote Lee Allen Peterson in the field guide Edible Wild Plants of Eastern/Central North America.

Tea is also made from the young nettle shoots and leaves. Prepared in soup, nettles are supposed to be pretty tasty, too.

Medicinally, the use of nettles has run the gamut from blood purifier to gastronomic aid. It's been used in treatments for arthritis and all manner of skin afflictions.

"Lakota create a root infusion to treat stomach pain, while the Potawatomi create a root infusion to reduce fevers," wrote Rochelle Peterson, who researched the plant as a student at Macalester College.

"The Ojibwa make a poultice out of the stewed leaves for heat rash … Chippewa are known to use nettle for battling dysentery and for 'the stoppage of urine' … The Winnebago utilize it for subduing allergy symptoms ."

Nettle is still used in alternative medicine. The University of Maryland Medical Center's website reported that contemporary uses of nettle are based on hundreds of years of traditional applications.

"Today, many people use it to treat urinary problems during the early stages of an enlarged prostate, for urinary tract infections, for hay fever … or in compresses or creams for treating joint pain, sprains and strains, tendinitis, and insect bites."

The fibrous property of nettles is well known. Burial shrouds made of nettle have been discovered in Denmark, dating to 2,000 B.C. In Europe, "nettlecloth" was used for German military uniforms during times of shortage in World War I.

Pottawatomi Indians used nettle cordage to make mats, baskets, and twine. Nettle fiber bags were woven by the Menominee, and Winnebago Indians incorporated nettle in the ceremonial "Sacred Bundle of the Tent of War," according to Peterson, citing recent research on flora of the Winnebago Indians. Other native peoples used nettle for fishing net, rope, thread and cloth.

Nettles have proved useful in dye-making as well. Depending on the mordant used, nettles can produce a green, greenish-yellow, or brown color.

All of nettles' nifty uses have created quite a fan base. It turns out that there is a community of nettle lovers out there - from foragers (those who like to hunt and gather wild edible plants) to advocates of alternative medicine, and artisans in dye-making.

There's even a "National Be Nice to Nettles" week in Great Britain (we missed it - it was last May). By chance, I stumbled on at least three "Nettle Festivals" on the Internet in different parts of the United States.

These nettle-file gatherings included gourmet nettle dishes, music, and - no kidding - nettle flogging. The latter is a practice that dates back to Roman times, when people would flog themselves with stinging nettle to treat ailments such as arthritis, dermatitis, hives, even lethargy. Nothing like getting whacked with stinging nettle to motivate you to move!

There are definitely downsides to nettles, as we've seen with their sting. They're considered invasive plants, and they've even reached noxious weed status in some areas. Nettles also contribute to the misery of people with allergies.

Those tiny, unassuming flowers are wind-pollinated - hence their pollen is designed to sail through the woods on the slightest breeze. And, it ends up in the sinuses of hay-fever sufferers far and wide.

Nettles are plants to recognize for both their good and not-so-good qualities. I can't guarantee that you'll be seeing nettle festivals in Kane County anytime soon, but you will come across these plants in the woods. Give the nettles a nod, and steer clear.

• Valerie Blaine is the nature programs manager for the Forest Preserve District of Kane County. You may reach her at blainevalerie@kaneforest.com.