I find it easier to dry on stem, then remove leaves after dried. I pull the stem though my thumb and finger and leaves easily detach. I use a dehydrator for drying.
Discussion
The results are in: I agree, dry it on the stem
They dry much faster if taken off the stem first, but if you need oregano fast, use it fresh instead of drying it.
I do not use a dehydrator for spices. I save the energy and let them dry out naturally. It takes longer, but it's probably less touch time. Snip, set on a plate out of the way and come back a few days later.
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