Opps, didn't see this question till now, and have just posted the answer in another thread, so please excuse my laziness while I cut and paste it.

Do the clippings need to be dry?

Though the leaves and stems contain THC (in smaller quantities than bud), it's bound up in the cellulose structure, so in order to release it into the butter/oil you're virtually cooking (simmering) them down into a 'mush'!

In the tests I've run, (N.B. this only applies when cooking leaves and stems) it makes no difference to the potency if you use fresh or dry material, in fact dried leaves and stems take slightly longer than fresh as you need them to soak up the water before they can begin to boil down and disintegrate. Fresh already contains moisture.

The only other differences I've found in using fresh/dried stems and leaves is the colour of the oil/butter as fresh makes it look greener (dried browner) and a slight difference in taste. But hey, seeing as both taste like crap on there own lol, you'll be using them with other ingredients anyway.

The science bit

You don't need to dry the trimmings first because the process of slow boiling/simmering the plant material also isomerizes the inactive CBD, and decarboxylates the THCA to THC, 'wringing' out every last drop of that 'spacey goodness'!

Flame takes a bow and heads to the kitchen lol