Smoking Herbs?!

Smoking Herbs?

Can smoking herbs such as wild lettuce and wild deaga(not sure if that is spelled right) cause you to fail a drug test? From what I have read, none of these seem to be illegal. But I would like to get some insight from people whom may know. I don't want to try these, but I don't want to lose my job over something as small as this. It's not like it's weed or coke. I would like a real informative answer, not a lecture.

Thanks

2 days ago
These herbs are supposed to be relaxing when smoked, or when mixed with tea.

i've read on some sites and it says you won't fail.
but who knows.