Unbeknownst to me, there are three main strains of Bt used to target specific pests. Bt is not a broad-spectrum pesticide. Information about the three strains and their specific targets can be found on the Colorado State University Extension Website site.
The most commonly used strain is Kurstaki,which targets caterpillars, including cabbage worms, tent caterpillars and leaf rollers. It is sold under the trade names Biobit, Dipel, MVP, Steward, Thuricide.
Mosquitoes and flies are treated with a separate strain Israelensis.
The third and fourth strains San diego/tenebrionis target beetles, like the Colorado Potato Beetle and others.
Check the ColoState page for more in depth info.
Sorry to scare you all. Bt is a safe pesticide, especially when compared with the alternatives.
Sheesh, I’d better stop using Wikipedia as the be all, end all. It certainly isn’t.
Thank you for clearing that up Daphne!