Will Falconer, DVM Moderator
Hi Andrew, the lemon eucalyptus in itself is a significant repellant, and can be bought in pure form from the vendors of essential oils. I've used it on some cattle I was milking, and it helped. I'd be concerned about the 70% "other" ingredient make up, however. Anything could be in there. The "inert" ingredients in Roundup are thought to be some of main problems, and as they are not the "active" ingredient, Monsanto is shielded from revealing them.
I got mine from Frontier Coop out of Iowa, but there are likely many sources of the pure E.O.