פירוש על כלאים 4:2

The space needed to tend a vineyard is a path 4 cubits wide so that the ox-drawn cart of the vintner may move there. Even though the House of Hillel forbid sowing if the minimal width is less than eight cubits, if somebody sowed illegally on a smaller patch neither the seeds nor the vines become “sanctified” as long as a minimal distance of 4 cubits is observed everywhere (Mishnah 7:3).

Reading of the Rome ms. Most older commentators emend the text to this reading since two parallel rows generate only one space between them. Venice and Leyden: תרין.

The extent of what becomes forbidden to use is detailed in the Halakhah.