They wouldn't work as construction workers, either? Besides, you're an economist. Why not let the law of supply and demand dictate the cost of picking cherries. You don't truly believe that unlimited third world immigration is good for our economy, do you? Immigration is controlled in a fashion similar to a water valve and would be virtually limitless as we allowed it. Picking cherries could be a lot cheaper if we wanted it to be. Do you want it to be cheaper? I mean frozen cherries can be had for $1.20 a pound. Go ahead. Tweak the labor supply. I bet you can get them even lower.
My point wasn't the cost of the labor for cherry picking, oranges, lemons, olives, potatos, etc. It's whether most Americans are willing to do that labor for the pay.
Perhaps you have, but I doubt it.