You are not to reap the aftergrowth of your harvest or gather the grapes of your untended vines. The land must have a year of complete rest.
KJV
That which groweth of its own accord of thy harvest thou shalt not reap, neither gather the grapes of thy vine undressed: [for] it is a year of rest unto the land.
ASV
That which groweth of itself of thy harvest thou shalt not reap, and the grapes of thy undressed vine thou shalt not gather: it shall be a year of solemn rest for the land.