Yikes Matt,
I don't think I have a grow bed big enough for a 40 foot tree
Witch's brooms typically grow about 25 feet up in these trees. And, there not easy trees to climb to begin with. Do you think going out to the site and placing an airlayer to collect in a year or so would work? I have never found a witch's broom on a tree small enough to collect.
As for the cuttings, I do actually have a hydroponic background, but I don't have a mister rooting chamber. Do you think it could be done using very oxidized water in a bubbler system? Or, would that be overkill on the moisture for a pine. I could probably even throw a mister system together pretty cheap in a small hand bucket, providing I can get a hold of the misters. But, I would probably rather go with the onsite airlayering if you think it would work more reliablely.