[bluGill]

Non-organic: roundup (from http://pmep.cce.cornell.edu/profiles/extoxnet/dienochlor-gly...) The toxicity of the technical product (glyphosate) and the formulated product (Roundup) is nearly the same. The acute oral LD50 in the rat is 5,600 mg/kg [Rat]

Organic: vinegar (http://www.sciencelab.com/msds.php?msdsId=9922769) (LD50): 3310 mg/kg [Rat]

Of course there are hundreds of different chemicals to look at, and LD50 is not the only measure. It is enough to back up my claim though.