He was given free rein to use Pathé's new sound department to create recordings of explosions and gunshots, something he referred to as "the reconstitution of the sonic ambience of the battles".

He used detectors from the army to search for and remove unexploded munitions due to the risk of the fake shells used in filming setting them off.

[2][3] The battles were described as "vibrant and convincing", with Bernard insisting that every actor have some form of combat experience.

Gunfire soon disturbs them as artillery begins to fall on the German trench, causing the pair to quickly return to the other three soldiers and retreat.

Three days later, the squad expects to be relieved by another unit, though the Germans were still digging and were, unbeknownst to them, setting explosives.

While the remaining members of the squad take shelter in a cemetery, one complains about the lack of water.

As Bouffioux watches through a gate, he sees a convoy of ambulances passing through, noting that there had been a lot that day.

They reach their dugout at night, hearing an injured French soldier calling for help just beyond their lines.

Hearing artillery landing nearby, the squad shouts for Lemoine, but he doesn't reply.

Artillery starts to strike near their trench, with one shell landing in front of Sulphart.

That night, Demachy attempts to crawl back to his trench, but is forced to stop by the pain and lay against a tree, where he stayed until his death.

When filming was finished, Bernard went with Dorgelès to visit President Paul Doumer to ask whether he would attend the premiere at Moulin Rouge.

They sat behind Doumer, with Bernard saying "I was incredibly moved and all the more so because you could have heard a pin drop in the auditorium.

Suddenly Roland Dorgelès nudged me with his elbow and pointed to the bowed head of President Paul Doumer, who was wiping away a tear.

[2] Speaking in 2015, Philip French, a writer for The Guardian, said of the film "with an all-male cast speaking military slang, and a soundtrack of natural sound, spine-chilling ordnance and incidental music, Wooden Crosses is an intense experience of pain, stoic endurance and survival.