Minnesota Seasons - stinging nettle


stinging nettle				More photos…
Urtica dioica ssp. gracilis

Nativity	Native
Status
Habitat	Wet to dry. Disturbed sites.
Flowering	June to September
Flower Color	Cream
Height	18″ to 72″



Identification	This is a 18″ to 72″ tall, erect, perennial forb that rises from a long rhizome. It often forms large colonies or dense patches. The stems are erect, stout, unbranched, and 4-angled. They are hairless or have straight, stiff, sharp, appressed hairs, with a few stinging hairs. The leaves are opposite, egg-shaped to lance-shaped, 2⅓″ to 8″ long, and ¾″ to 3″ wide. The blades are rounded, rarely heart-shaped, at the base, and taper to a point at the tip. The upper surface is hairless or has minute, fine, short hairs, but rarely has a few stinging hairs. The lower surface has stinging hairs. The margins are coarsely toothed, the teeth averaging 1 ⁄16″ to ⅛″ deep. The leaves droop downward slightly on ½″ to 2½″ long stalks that have stinging hairs. At the base of each leaf stalk are a pair of 3 ⁄16″ to ⅝″ long, lance-shaped, leaf-like appendages (stipules). The inflorescence is a branched, spreading, elongated cluster drooping downward on a stalk rising from the middle and upper leaf axils. Individual flowers have either male or female reproductive parts, but not both (unisexual). Both male (with stamens) and female (with pistils) flowers are borne on all plants with the female flowers above the male flowers. Male flowers are ascending, ⅛″ wide, with 4 green petal-like sepals and 4 white stamens. There are no petals. Female flowers are loose and bent backward, ⅛″ wide, with 2 inner, egg-shaped sepals enclosing the ovary, and 2 outer, linear, narrowly spoon-shaped, or lance-shaped, petal-like sepals. There are no petals. The fruit is an egg-shaped achene.

Similar Species	Canadian woodnettle (Laportea canadensis) leaves are alternate and broader. The stem zigzags. Small-spike false nettle (Boehmeria cylindrica) has no stinging hairs.

Range			Sources: 2, 3, 5, 7.

Sightings	Avon Hills Forest SNA North Unit Banning State Park Big Stone Lake State Park Black Dog Preserve Blue Devil Valley SNA Bonanza Prairie SNA Boot Lake SNA Camden State Park Cannon River Wilderness Area Carley State Park Cedar Mountain SNA Chamberlain Woods SNA Charles A. Lindbergh State Park Cherry Grove Blind Valley SNA Chimney Rock SNA Clear Lake SNA Cottonwood River Prairie SNA Crow-Hassan Park Reserve Des Moines River Prairie SNA Dodge Nature Center Elm Creek Park Reserve Englund Ecotone SNA Falls Creek SNA Felton Prairie SNA Shrike Unit Flandrau State Park Fort Ridgely State Park Glendalough State Park Glynn Prairie SNA Hardscrabble Woods / MG Tusler Sanctuary Hastings Sand Coulee SNA Hastings SNA Hayes Lake State Park Holthe Prairie SNA Hythecker Prairie SNA Iron Horse Prairie SNA Kilen Woods State Park Lake Carlos State Park Lake Elmo Park Reserve Lake Maria State Park Lake Rebecca Park Reserve Lebanon Hills Regional Park Long Meadow Lake Lost Valley Prairie SNA Louisville Swamp Lundblad Prairie SNA			Maplewood State Park Mary Schmidt Crawford Woods SNA Mille Lacs Kathio State Park Minneopa State Park Mound Spring Prairie SNA Murphy-Hanrehan Park Reserve Myre-Big Island State Park Nelson Wildlife Sanctuary Old Mill State Park Ordway Prairie Oronoco Prairie SNA Osmundson Prairie SNA Ottertail Prairie SNA Partch Woods SNA Prairie Smoke Dunes SNA Racine Prairie SNA Rice Lake State Park Richard M. & Mathilde Rice Elliott Prairie SNA River Terrace Prairie SNA Rock Ridge Prairie SNA Rushford Sand Barrens SNA St. Croix Savanna SNA Savage Fen SNA Sedan Brook Prairie SNA Seminary Fen SNA Sibley State Park Spring Creek Prairie SNA Staffanson Prairie Strandness Prairie Town Hall Prairie Twin Lakes SNA Uncas Dunes SNA Upper Sioux Agency State Park Wild Indigo Prairie SNA Wild River State Park William O’Brien State Park Yellow Bank Hills SNA Zimmerman Prairie Zumbro Falls Woods SNA

Comments	The stinging hairs are hollow and act like syringes injecting histamine, acetylcholine, and a neurotoxin. They produce an intense burning and itching sensation.

Images
Plant

Inflorescence

Taxonomy	Family:	Urticaceae (nettle)

Synonyms	Urtica californica Urtica cardiophylla Urtica dioica var. angustifolia Urtica dioica var. californica Urtica dioica var. gracilis Urtica dioica var. lyallii Urtica dioica var. procera Urtica gracilis Urtica lyallii Urtica lyallii var. californica Urtica major Urtica procera Urtica serra Urtica strigosissima Urtica viridis

Common Names	California nettle slender nettle stinging nettle tall nettle