The active ingredient in Roundup binds tightly to soil particles making it stay where it is applied. It is also of very low toxicity to aquatic organisms. These are reasons Roundup is commonly used in riparian areas for invasive weed control in preference to some other kinds of herbicides. The surfactant component in Roundup is considerably more toxic to aquatic organisms, but as long as no overspray into water takes place it should not present a problem in most situations. Make sure there is no drifting or dripping of material into water. If you cannot assure this, or you want to do control work right on the edge of the water you may wish to use aquatic versions of Roundup: Aquamaster or Rodeo, both of which contain just glyphosate and are labeled for aquatic use.

The researchers at the University of Florida seem to think that glyphosate containing products should not be used near water because they are quite toxic to aqautics.

Here is a link that might be useful: UF on glyphosate products

"Not be used near water because they are quite toxic to aqautics"? Anyone actually reading the link would see that the researchers at the University of Florida emphatically state exactly the *opposite*.

They stated: "The purpose of this article is to put these recent publications in perspective relative to aquatic and terrestrial natural area weed management and explain why land managers should *continue* to use glyphosate-containing products to protect managed habitats from weeds *without concern* for unreasonable adverse environmental impacts."

"Field studies to assess impacts ... indicate that glyphosate herbicides registered for terrestrial application are *not likely to result in adverse effects to amphibians* when used according to label directions (Wojtaszek et al. 2004, Thompson et al. 2004)."

"Applicators who apply glyphosate-containing products according to instructions on the herbicide label and on the surfactant label *will have an acceptable margin of safety* to wildlife."

"Land managers *should continue to use* glyphosate-containing products to protect managed habitats from weeds without concern for unreasonable adverse environmental impacts..."

"There are *no data that suggest* the use of glyphosate-containing herbicide products is responsible for global declines in amphibian populations."

This is why conservation groups such as the Nature Conservancy who care for some of the world's most sensitive habitats use Roundup for removal of invasives.

Products containing glyphosate which can be used near waterways don't have the word Roundup in their names.

One such product is Habitat.

Take a look at this pub from Univ of California
http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7431.html

Here is a link that might be useful: ways to kill poison oak from UC

To be clear, Roundup products can be used in non aquatic situations according to label directions. That includes near waterways, but not in them. For applications where there is threat of actual drift or application to waterways, use of aquatically labeled forms of glyphosate are legal, such as Rodeo, Aquamaster etc. Habitat is not a glyphosate based herbicide. Its active ingredient is imazapyr.