Hayday is the day you cut and mow the grass for hay for the cows and horses to eat later on as storage.
It's an everything goes day after sitting idle for some weeks and months waiting for the hay to grow and get mature and then for the weather to be optimal so it doesn't get rained on or blown away while harvesting.
Hay needs drying time and sometimes turned in the drying process.
If it's put up too fresh cut it will mold and go to rot and won't store well.
Hayday is a very important day.
Nobody wants the crop to get ruined and it's hard to get everything required right and your horses and cattle and income rely on it
Hayday is a very exciting day and a lot gets done fast with everybody participating fully.
Then it's over as quickly as it started sometimes.
Winding things up.
All the stops are out and everything goes.
"The fish are in"
The boats have returned.
D-Day I think it's called in war.
The physicists are really going to have a high ol time with this once it becomes known to them..