Thanks, Trent (and others for your advice and encouragement)

I used Cutrine Plus, and applied it with a hand pump sprayer from the shoreline (my pond is only 60' X 90') diluting the product 2:1 with water. In retrospect, my timing was bad, as I applied the product just a couple days before the frogs appeared and started laying eggs.

I spoke with a couple of folks at MSU, and the consensus is that I killed the frogs with the Copper. &^$#(#$

I'll take your advice, Trent, and use a high volume sprayer or perhaps wait until after the frogs are gone and tadpoles hatched next year.