In contrast to agricultural farming, orchards need to be tended with light-weight tractors of less than 100 horse power. The tracks for these vehicles are limited by the narrow rows of trees. This means they have to drive up and down the same tracks over and over again. Heavy marshy ground can be as hard as concrete when dry, but as soft as butter after heavy rainfall.
The heavier the tractor, the more the ground is compressed under the weight of their wheels, which makes it less fertile. For optimal root growth it is crucial that we do not compress the earth with heavy machinery.