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

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

Flower

No true flowers; some submerged leaves develop spores, but they are not viable

Root

No true roots, but submerged leaves act as roots

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

Learn more about the author(s)

Heidi Kratsch

Also of Interest:


Know Nevada Insects: Aphids This publication explains the biology and general management of aphids, one of the most common garden pests in Nevada. There are many alternatives to chemicals when treating aphids, including using native predators and protecting plants with lightweight physical covers. Burls, K. and H. Kratsch 2020, Extension, University of Nevada, Reno
Aphid Trouble in Alfalfa? Here’s How to Stay Ahead This Season Spring aphid pressure is back in Nevada alfalfa fields. Learn how to identify blue alfalfa aphid, assess economic thresholds, and take timely action using IPM strategies to protect your yield. Waaswa, A. 2025, Extension, University of Nevada, Reno, Blogs
All About Aphids! Aphids are one of the most common garden and landscape pests. Here are a few tips on control. Hansen, N. 2020, Extension, University of Nevada, Reno, YouTube Channel
All About Aphids! Aphids are one of the most common garden and landscape pests. Here are a few control tips. Hansen, N. 2020, Extension, University of Nevada, Reno
Aphids and Their Management in Home Gardens Aphids can be one of the most persistent and noticeable pests in the home garden. They are especially prominent in the spring when new growth is forming on plant material. This publication covers identification, life history of aphids and the various methods of natural and contr... McKie, P., and Johnson, W. S. 2002, Extension, University of Nevada Reno, FS-02-10

Nevada Noxious Weed Field Guide – Giant salvinia