policies

so when looking to the salt buildup in the farm fields I found a great solution,
it is salt grass, http://people.westminstercollege.edu/faculty/tharrison/gslplaya99/saltgrass.htm
it takes the salt out of the soil and puts it on to the leaves,
you could harvest the grass and wash the salt off,
perfect solution ?
you could grow it for a few years on a plot and remove the salt from the field,
but there is an issue there,
financial policy that is in most countries does not let many people have a big farm plot that is not making money for a few years,
it is either land taxes or loan payments that really do it,
so my question is
is it really a good idea as a civilization to set financial policies that make sure we loose farmland in the not so distant future ?
the government pays people to not grow on some farm plots (the farm bill)
so why not pay farmers to get the salt out of the land ?
or at least not make self interest break all of the farmland