42-year-old Byfield, who enjoyed two spells at Banks's Stadium during a well-travelled professional career, recently resigned as manager of Stratford Town after taking charge of just six games.
36-year-old Birch, a product of the Saddlers' youth system , where he would go on to make over fifty first-team appearances, has resigned as manager of the Wood after struggling to balance work commitments with his position at the club, has agreed to remain part of the set up, taking the position of Director of Football.
Wood chairman Justin Hodgin also confirmed that Richard Teasdale will operate as Assistant Manager, with Gavin Hurren becoming First-Team coach, whilst Jehmiah Richards has been named as the club's Head Physio.
A statement, written by chairman Hodgin and released via the club's official Facebook page confirms; "Following a number of meetings over the past week, we can now confirm that Manger Gary Birch will be stepping down as First Team Manager with immediate effect and has been appointed Director of Football at Walsall Wood FC.
"The following decision has not been taken easily and has been made due to a change in Gary's personal work commitments. Gary's new position will be to assist with first team duties and help us develop an improved structure at Youth level for Boys and Girls.
"Gary will assist myself, as Chairman, the board members and committee in continuing the development of all aspects of Walsall Wood FC. This is a very exciting time to be part of Walsall Wood FC and the club are delighted Gary has accepted this role.
"We are delighted to announce the appointment of Darren Byfield as First Team Manager with immediate effect. Darren brings with him a wealth of experience and connections in the non- league pyramid. Darren will be assisted by Richard Teesdale (Assistant Manager) , Gavin Hurren (First Team Coach) and Jehmiah Richards (Physio Therapist).
"We look forward to this new structure off the field and hope you all continue to show your magnificent support as you have always done."