City of Owosso issued the following announcement on Dec 28.
The City of Owosso's Department of Public Works will pick up discarded Christmas trees January 3 through January 28, 2022. No artificial trees will be accepted. Remove all plastic covers, decorations and tree stands.
Place trees to be picked up at the curb. You do not need to call to schedule tree pick-up.
Original source can be found here.