Hm...I'm thinking maybe pesticide shouldn't be a
concrete noun: not a substance, but an act that a person can carry out, like homicide or fratricide. Perhaps like so:
Pesticide: the act of killing with pronounced contempt for the victim's place in the ecosystem.
Over the past couple years, I've been guilty of pesticide in the case of house flies and fruit flies, garden slugs, bitter lettuce, and pellitory-of-the-wall. The last time I used chemical methods was spraying some generic Windex on ant trails years ago, and I used ant bait a few times before that.
Thanks, Emerson, for pointing this out. It's very difficult to become aware of one's pre-conceptions, and science of the sort you linked to can really help.
I'd also like to second the notion that there is no "best" without context.
"the qualities of these bacteria, like the heat of the sun, electricity, or the qualities of metals, are part of the storehouse of knowledge of all men. They are manifestations of the laws of nature, free to all men and reserved exclusively to none." SCOTUS, Funk Bros. Seed Co. v. Kale Inoculant Co.