Most conservatives — at least mainstream conservatives — believe in economic rights. Individuals should be able to freely sell their labor to any buyer or enter almost any profession and sell goods and services to the market as a matter of freedom of exchange. Any restrictions on these rights are justified only if there is some overriding general welfare concern.
The farmers had overfarmed their land and had lost the valuable top soil. Take into consideration a drought as well, the high winds of the plains took the overfarmed (and dry) soil and blew it across the land.
