Measure the distance between two trees at the intended height of the arch’s underside.
Cut a brace 2 feet shorter than the determined width to fit between the two trees and begin the “bend” of the archway.
Bow the trees toward each other and secure the ends of the brace to each tree using rope. Alternatively, make the brace with crotched or rounded supports at each end and omit the use of rope.
Pull or winch the treetops to meet in the center of the archway above the brace. Use as little force as possible to avoid cracking or breaking the trees. Intertwine the branches together and securely bind them with rope to encourage horizontal growth.
Prune the trees to remove the excess undergrowth and create a rounded arch. Continue to prune the trees over the years or let them take on a natural appearance as they grow.