Identifying Dog Nettle (Urtica urens)

Take great care when identifying wild plants and fungi, this blog is not a resource to be taken by itself and further resources will be linked. Consult other sources and double check. While foraging is an extremely rewarding and useful skill, numerous common plants and fungi can make you sick or kill you. Be absolutely sure of what you’re eating and, when gathering, ensure you leave enough not only to ensure the survival and growth of the species but also enough for others to enjoy, from the human and more-than-human communities. Also cultivate an awareness of contamination and pollution – wastewater runoff, spraying, exhaust fumes – as this should affect your decision to harvest.

The Plant

Urtica urens is a prolific edible “weed” from the stinging nettle (Urticaceae) family. It is native to Eurasia but grows abundantly throughout New Zealand on pasture land, under trees, and in gardens. Stinging nettles thrive in full sun but I have found them growing well in a lot of shaded areas aswell. Urtica urens directly translates to “burning nettle” referring to the harsh burning sting which occurs when a nettle is touched.

Description

Dog nettle is an annual stinging nettle growing up to 75cm tall. Urtica urens is also referred to as dwarf nettle as it is much smaller than some of the other species in the stinging nettle family. The leaves are generally a vibrant medium green and are sharply toothed around all of the edges. The stems and leaves are covered with tiny stinging hairs, known as trichomes, and the leaves will grow from the stem close together so when you look from above there appears to be four leaves repeating down the stem until it begins to branch off lower down. The stem of Urtica urens is paler than the leaves and this nettle will produce small clusters of greenish white flowers from where the leaves join the stem from spring though to summer.

Ecology

I have come across Urtica urens in the North and South Islands of New Zealand. It appears to grow best in slightly disturbed soil that is rich in organic matter, such as animal pastures, in orchards, and in people’s home gardens. Whilst dog nettle is an annual it grows in large clusters and spreads prolifically and so is available to harvest all year round.

Nutritional/Medicinal Information

The leaves and flowers of Urtica urens are a powerful diuretic and have been used to treat joint pain. Other medicinal uses include helping with hay fever, urinary tract issues, and sore muscles through it’s anti-inflammatory properties. Pregnant women should not use nettle as it can alter the menstrual cycle and contribute to miscarriage. The Urtica species are a great source of iron largely due to it’s high concentration of vitamin C which increases iron absorption.

Possible Lookalikes

Red dead nettle (Lamium purpureum) looks somewhat similar to dog nettle if seen from afar but red nettles do not sting and are not part of the Urticaceae family. Red dead nettle tends to be more sprawling, the leaves have softer toothed leaves, and they produce pretty purple flowers. It is also edible so don’t worry if you accidentally harvest it!

Tree nettle (Urtica ferox) is a species of nettle which is endemic to New Zealand. Tree nettle is still edible and medicinal but should be used and harvested cautiously as stings from this nettle (in high concentrations) can cause paralysis, convulsions, confusion, and in one reported case death. Tree nettle will grow significantly bushier and taller than dog nettle.

Interesting Facts

The trichomes on the stinging nettle are made from silica and calcium and act like hypodermic needles with a protective tip. When the tips are broken off through touch the needle will inject the skin with a fluid containing histamines, formic acid, and acetylcholine, causing a red, itchy, stinging rash which should go away within a couple of hours.

Dog nettles are considered the most painful nettles to be stung by.

Apparently the Zulu people in Africa considered this plant an aphrodisiac.

Leaf extracts of Urtica urens has been shown to have nematocidal properties against the citrus nematode.

Storage & Cooking

Pick nettles while they’re young and fresh (with gloves) and are best used straight after harvesting or store in the fridge. You can also hang bunches of nettles up to dry or dry in a dehydrator or oven. You can then use the dried or fresh leaves in a tea or grind them into a powder.

Urtica urens fresh, dried, or powdered is delicious in soups, pesto’s, pasta dishes, teas, stocks, and smoothies. The leaves must be cooked, boiled, or pulverised to remove the sting from the nettles. Enjoy my fellow foragers!

Further Reading

Invasive Species Compendium

iNaturalist