If you are bringing the trees from some place other than cutting them on the banks, you will be fine. Keep them deep enough to not be a navigation hazard and the authorities will look the other way. I wouldn't try to notify anybody, you would probably just confuse most of them with your request.

Word of advice, if you want to fish the beds you put in without having to wait in line for them, I would put them somewhere else besides Jonathan Creek. Pick yourself an out of the way cove or drop on LBL side or in one of the smaller coves on the west side. Your chances of it not becoming a public hole are much greater. Anything put in will eventually become public knowledge, it will just take longer somewhere besides the major bays.

As for current conditions, lots of the bays are frozen a good ways back.