KDO (or anyone)

For a drip system in a climate that freezes, that is installed in an area that is level, what precautions does one have to take for the winter months? We'll have months at a time that temps are below freezing. The system that I will be installing is too large to pick up every year. (25 or so fruit trees)

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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).