UC IPM Online UC ANR home page UC IPM home page

UC IPM Home

SKIP navigation

 

How to Manage Pests

Identification: Weed Photo Gallery

Burning nettle

Scientific name: Urtica urens (Nettle Family: Urticaceae)

Click on image to enlarge

Life stages of Burning nettle seedling spines mature plant seeds

Burning nettle, an annual broadleaf plant, behaves as a winter annual in the interior valleys of California and grows year-round on the coast, where it is especially troublesome. Burning nettle is found througout much of California, to 9800 feet (3000 m), except for the Klamath Ranges, upper elevations of the Cascade Range, and deserts. It inhabits agricultural lands and other disturbed sites. Skin contact with the hairs of this plant usually causes a burning or stinging sensation for several minutes. This may be followed by a longer period of itching or numbness. A related species, stinging nettle, Urtica dioica, also causes a burning or stinging sensation.

Habitat

Crop fields, orchards, vineyards, gardens, ditches, nurseries, roadsides and other disturbed, unmanaged places.

Seedling

Cotyledons (seed leaves) are rounded, smooth edged and have a small notch at the tip. The first true leaves are oval, sparsely hairy, have distinctly toothed edges, sit atop short stalks, and are opposite to one another along the stem.

Mature plant

Mature plants are 5 to 24 inches (12.5—60 cm) tall, with square stems that branch from the base. Most of the plant's stinging hairs are located on the stems, leaf stalks, and lower surface of leaves. Leaves are elliptical to egg shaped, have toothed edges, and besides stinging hairs, have short non-stinging hairs, and often minute glands. Burning nettle has a slender taproot, often with many lateral roots. The related stinging nettle plant is taller and its leaves are less rounded than those of burning nettle.

Flower

Flowers bloom from January through April, but year-round in milder coastal climates. Small greenish white flowers cluster in the junction where the leaf stalk and stem join.

Fruit

Fruit are tiny, less than 1/12 of an inch (2 mm), smooth, egg shaped, and contain a single seed.

Reproduction

Reproduce by seed.

Related species/Similar looking plants

Stinging nettle

More information


Statewide IPM Program, Agriculture and Natural Resources, University of California
All contents copyright © 2011 The Regents of the University of California. All rights reserved.

For noncommercial purposes only, any Web site may link directly to this page. FOR ALL OTHER USES or more information, read Legal Notices. Unfortunately, we cannot provide individual solutions to specific pest problems. See our Home page, or in the U.S., contact your local Cooperative Extension office for assistance. /PMG/WEEDS/burning_nettle.html revised: October 31, 2011. Contact webmaster.