Axially adjustable connectors for truss legs and related systems and methods

A truss foundation system for supporting single-axis trackers comprising:

• a pair of adjacent truss legs;
• and
• an adapter joining above-ground ends of each leg of the pair of adjacent truss legs and having at least one tracker bearing support surface, wherein each leg of the pair of adjacent truss legs comprises:
• a first member having an external thread form proximate to a first end and a first stamped thread form proximate to an opposing second end;
• a second member having a second stamped thread form at a first end dimensioned to mate with the first stamped thread form of the first member;
• and
• a retaining nut that receives a portion of the second member when the second stamped thread form is threaded over the first stamped thread form to form a single structural member.

A foundation leg system comprising:

• a first member having an external thread form proximate to a first end and a first stamped thread form proximate to an opposing second end;
• a second member having a second stamped thread form at a first end dimensioned to mate with the first stamped thread form of the first member;
• and
• a retaining nut engaged with the first stamped thread form and receives a portion of the second member when the second stamped thread form is threaded over the first stamped thread form to form a single structural member.