A liquid manure spreader includes a spreader vehicle, a transversely extending injector boom having at least one outer boom section pivotable between a transversely-oriented position and a vertically-oriented position, at least one first actuatable linkage assembly for translating the boom vertically between a lowered working position and a raised position, and at least one second actuatable linkage assembly for arcuately pivoting the boom about an axis parallel to the transverse axis between a highest vertical height position and a lower transport position when the boom is in the raised position and the at least one outer boom section is in the vertically-oriented position.