Some of the labor problems farmers face, which make them claim that they need illegal cheap labor to continue to farm, are self inflicted: they've made a decision to produce crops that have to be picked by hand, unlike wheat, for example. There are also mechanical solutions, but farmers aren't interested in those as long as cheap labor is available.

George Washington was serious farmer—he once wrote to a friend that

I think that the life of a Husbandman is of all others the most delectable. It is honourable. It is amusing. And with Judicious management it is profitable. To see plants rise from the Earth and flourish by the superior skill and bounty of the labourer fills a contemplative mind with ideas which are more easy to be conceived than expressed. The more I am acquainted with agricultural affairs the better I am pleased with them. I can nowhere find so great satisfaction as in those innocent and useful pursuits.

Of course, if you learn anything about George Washington, you learn that he was slave owner. In fact, it may be the only thing you learn about him in a modern school. Slavery is, of course, the ultimate form of cheap labor. Washington didn't approve. Paul Johnson writes:

He regarded tidewater farming in Virginia as inefficient and degrading, with no future. It involved slavery. He always owned slaves, and at one time had more than three hundred (mainly belonging to his wife), but he regarded the institution as wrong and incurably wasteful. In the 1760s he farmed over 20,000 acres. Many rich English earls and dukes had no more. Whence the difference in their incomes and his? Because the best English farming was a judicious mixture of arable, pasture and stock raising, all for the market. By contrast Virginia tobacco was bought by London agents, who did the marketing themselves, got the profits and usually had the American planters in their debt. It was a formula for laziness and improvidence. So Washington spent his life switching from planting to scientific farming. He raised wheat, less labor intensive-a skilled plowman could do the work of forty slow-hoeing slaves—but it demanded large numbers of draft animals and they in turn needed large quantities of hay. So he planted corn fodder alongside wheat, raised root crops, forage crops like clover and alfalfa and put out fields to cattle and hogs. They, in turn, and his plow horses, produced manure which he used as fertilizer. He grew peas and potatoes, planted vines and set up fruit and vegetable gardens on all his farms.[Heroes by Paul Johnson.]

Of course, most of today's complaining farmers are not George Washington. One way you can tell them from George Washington. that they can tell a lie—usually about crops rotting in the fields.