Isatis herba

crops. A field cultivated so well, which
among us is for the most part black and
of an ash-gray color, is quite good,
although in this business the color of
the earth is not much to be desired,
since it is an uncertain author of
goodness and sometimes a deceitful
messenger. Or they cultivate and
turn the earth with a two-pronged
mattock original: "bipalio"; a heavy iron tool used for digging, having
likewise dug up the lowest part of it.
For the more often or with greater
diligence the field is worked, the
purer and more vigorous fruits it
produces, and with the earth being
freer of those things that mix in and
introduce themselves, such as herbs
of another kind, it can be freed by
breaking or tearing up their roots
with the plow or with the two-
pronged mattock, so that it may not
degenerate into a meadow. For other-
wise, if this diligence in cultivating
the field is neglected, the field is
accustomed to being overly infested
with herbs of another kind, just as
Ovid says in Tristia, Book 5, Elegy 13: