As the tractor collects the hay, the baler if constantly "rolling" it into a huge cube. Once it reaches capacity (not sure if it is by weight of circumference) an alarm sounds to signify the bale needs to be released. Matthew backs up the tractor then opens the baler to release the bale, which rolls out behind. He closes the baler and continues down the windrow to pick up the remaining hay...until the field is clean!
