Hi Tzeu
https://www.historyonthenet.com/medieval-farming-the-farming-year/   February, March, July and 'Autumn' (the last in the text)

I think you will find that, as with modern farm contracting, there were were some fairly complicated and varied arrangements. Not everyone may have had a plough but unlike the oxen that did not need feeding so maybe even less people had there own oxen.

Similary I don't think it is clear to us as listeners to a song where, say, a weaver fitted into the local economy and society. I think some were itinerent, coming to use a housholds loom when required, others may have had their own but maybe wove other people's thread. I think those are the sort of details of social history that might show if a song was written by and for 'the folk' - but also may lead to us missing subleties of the story.