Blecker, L., Creech, E., Dick, J., Gephart, S., Hefner, M., Kratsch, H., Moe, A., Schultz, B. 2020, Nevada Noxious Weed Field Guide – Giant salvinia, Extension, University of Nevada, Reno, Field Guide

Stem

  • Floating aquatic plant that grows at water surface; often highly branched
Photo of giant salvina weed with green leaves
 

Leaves

  • 1 submerged and 2 floating leaves whorled around stem at each node
  • Floating leaves are oval, flat, 1-2.5 in. wide and covered with short hairs less than 0.12 in. long that are shaped like an egg-beater 
  • Submerged leaves are white to brown, fine, hair-like, up to 1 in. long and resemble roots
Photo of giant salvina weed with greent leaves.

 

Flower

  • No true flowers; some submerged leaves develop spores, but they are not viable
Photo of giant salvina weed with green leaves
 

Root

  • No true roots, but submerged leaves act as roots
Photo of giant salvina weed with green leaves
 

 

Other

  • Grows best in areas that do not experience extended periods of freezing temperatures; not known to occur in Nevada
  • Perennial; reproduces by stem fragments; can form a mat over 1.5 ft. thick under favorable conditions
  • Listed on the Federal Noxious Weed List
 

Control

  • Mechanical removal can be effective but must be done repeatedly; escaped stem fragments can form new plants
  • Aquatic herbicides such as diquat and fluridone are effective 

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