Honestly... nothing is frog friendly. Not the organic solutions. Not the other solutions. Nothing. But here's the thing. To get a home remedy to kill a weed or moss or lichen or what ever...you need epic concentration. To get Glyphosate to kill the average weed it's like 10 ml per litre of a 360 grams per litre concentrate and it has a half life of less than 36 hours...less if it rains. Simply because the compound is biologically available. Home solutions are about overwhelming something with shit living things don't like..
In the end, the solution to pollution is dilution.
From Wikipedia
The
half-life of glyphosate in soil ranges between 2 and 197 days; a typical field half-life of 47 days has been suggested. Soil and climate conditions affect glyphosate's persistence in soil. The median half-life of glyphosate in water varies from a few to 91 days.
[55] At a site in Texas, half-life was as little as three days. A site in Iowa had a half-life of 141.9 days.
[87] The glyphosate metabolite AMPA has been found in Swedish forest soils up to two years after a glyphosate application. In this case, the persistence of AMPA was attributed to the soil being frozen for most of the year.
[88] Glyphosate adsorption to soil, and later release from soil, varies depending on the kind of soil.
[89][90] Glyphosate is generally less persistent in water than in soil, with 12- to 60-day persistence observed in Canadian ponds, although persistence of over a year has been recorded in the sediments of American ponds.
[86] The half-life of glyphosate in water is between 12 days and 10 weeks.
[91]