Why is there always 1 tree planted in farmers fields ?

various reasons , bounderies , shade for animals , but mostly remenants of once was

Most of the land is being used for growing. They usually left a tree or two next to the house for shade during the summer months.

I think that sometimes early farmers left trees to mark out the boundaries of their properties. Maybe they are the remnants of earlier farms merging. I notice these trees are always the most beautiful and symmetrical because they don't have to compete for sunshine.

Farmin's hot work in the summertime, son. Ya gots to have a big ol tree to snooze under.

at Poppa's farm, same deal.... he'd be up before sunup plowing with Ol'Bess... long about lunch time, he'd be about at the center, tie Bess to the tree in the shade and come to the house for lunch.....

cuz the old lady wanted it