Utricularia macrorhiza Leconte
Lentibulariaceae (Bladderwort Family)
Synonym(s): Utricularia vulgaris, Utricularia vulgaris ssp. macrorhiza, Utricularia vulgaris var. americana
USDA Symbol: UTMA
A small floating plant with 6-20 bilaterally symmetrical, yellow flowers in each rather stout, erect raceme.
This species also occurs in Eurasia. Of possibly five Utricularia species in the West, several difficult to distinguish, this has the largest flowers. Another species easy to identify is Mountain Bladderwort (U. intermedia), with bladders on special branches distinct from the leaves. In all species of Utricularia the bladders are elaborate traps. When a small organism brushes hairs near a bladder pore, the pore's tiny door opens inward and water rushes inside, carrying the organism with it. The door quickly closes, the trapping process taking 1/460 second. Enzymes digest the victim. Comparatively large organisms, such as mosquito larvae, may be caught in the door; if the door is repeatedly triggered, they are then digested little by little.
From the Image Gallery
Bloom InformationBloom Color: Red , Yellow
Bloom Time: Jun , Jul , Aug , Sep
DistributionUSA: AK , AL , AR , AZ , CA , CO , CT , DC , DE , FL , GA , IA , ID , IL , IN , KS , KY , LA , MA , MD , ME , MI , MN , MO , MT , NC , ND , NE , NH , NJ , NM , NV , NY , OH , OK , OR , PA , RI , SC , SD , TN , TX , UT , VA , VT , WA , WI , WV , WY
Canada: AB , BC , MB , NB , NL , NS , NT , PE , QC , SK , YT
Native Distribution: Throughout much of North America.
Native Habitat: Ponds and slow-moving water.
Growing ConditionsLight Requirement: Sun
Soil Moisture: Wet
BenefitWarning: This plant's tiny stinging hairs contain an acid that can cause a severe, burning skin irritation.
Conspicuous Flowers: yes
National Wetland Indicator Status
Web ReferenceWebref 30 - Calflora (2018) Calflora
Webref 23 - Southwest Environmental Information Network (2009) SEINet - Arizona Chapter
Additional resourcesUSDA: Find Utricularia macrorhiza in USDA Plants
FNA: Find Utricularia macrorhiza in the Flora of North America (if available)
Google: Search Google for Utricularia macrorhiza
MetadataRecord Modified: 2023-04-10
Research By: TWC Staff