Shevi'is, Chapter Seven, Mishnah 2. This Mishnah presents the counterpart to the previous one: there we dealt with things that are no longer found in the field, meaning that they cease to exist there after a certain point in the season - and it is those that are subject to the law of bi'ur (removal). Our Mishnah deals with things that are not subject to bi'ur, because they remain in the fields, permanently attached to the ground.
The text of the Mishnah:
"V'od klal acher amru" - the Sages stated a further principle. "Kol she'eino ma'achal adam u'ma'achal behemah u'min hatzov'im" - anything that is not human food, and not animal food, and not among the plants used for dyeing. "U'mitkayem ba'aretz" - or even if it is human food, or animal food, or a dye, but it endures in the ground and does not disappear, since its season never ends and it is always to be found in the soil, as we will see in the examples.
"Yesh lo shevi'is u'ldamav shevi'is" - the laws of Shemittah apply to it and likewise to the money received for it. "Ein lo bi'ur v'ein l'damav bi'ur" - it is not subject to bi'ur, and neither is the money for which it was exchanged. The reason: bi'ur applies only to things that disappear, whose season has passed and which can no longer be found in the field, to the point that even the wild animals of the field can no longer eat of them - and at that point even what is in the house must be disposed of. But something that endures in the soil and never disappears, such as a root and the like, is not subject to bi'ur.
An alternative version of the text of the Mishnah:
There is another version of the wording of our Mishnah, which is easier to understand: "Kol shehu ma'achal adam u'ma'achal behemah u'min hatzov'im" - not "that is not" but "that is": anything fit for human food or animal food, or that can be used for dyeing, "u'mitkayem ba'aretz" - and nevertheless it endures in the ground, unlike the previous Mishnah, where it did not endure in the ground - such produce is subject to the laws of shevi'is, but it is not subject to bi'ur.
"Eizehu" - the examples the Mishnah lists:
"Ikar luf hashoteh" - the root of the wild luf.
"V'ikar hadandanah" - the root of the mint plant.
"V'akarvanin, v'chalbitzin, u'buchriya" - additional plants. There is no benefit in translating their names, since even the accepted translations of these plants are unfamiliar to us today.
"U'min hatzov'im: hapuah v'harichpah" - from among the plants used for dyeing, and these too remain permanently in the ground.
"Yesh lahen shevi'is v'lidmeihen shevi'is" - the sanctity of shevi'is applies to them and likewise to their money, to the coins received in exchange for them. "Ein lahen bi'ur v'lo l'dimeihen bi'ur" - the law of bi'ur does not apply to them, nor to their money.
The dispute between Rabbi Meir and the Sages regarding the money:
Rabbi Meir holds that the money is an exception: "Dimeihen misba'arin ad Rosh Hashanah" - money received for these fruits is subject to bi'ur, and one must dispose of it by Rosh Hashanah. Apparently Rosh Hashanah was the time of bi'ur for the produce listed in our Mishnah.
"Amru lo" - the Sages answered him: the produce itself is not subject to bi'ur, since it remains in the field, and if so, the money follows all the more so - certainly coins received solely in exchange for that very produce are not subject to bi'ur.
Rabbi Meir, however, is stringent, because the law of coins is different: when one sees the object itself, it is evident that it belongs to the category of things not subject to bi'ur, since it remains in the ground; but with coins there is no way to distinguish between coins that came from things subject to bi'ur and coins that came from things that are not. Therefore we are stringent with coins and say that all coins are subject to bi'ur, even though by the letter of the law there would be no basis to obligate them - since one cannot tell one coin apart from another, the law of bi'ur is applied to all coins.
In summary: This Mishnah teaches a further principle, serving as the counterpart to the previous Mishnah: something that endures in the ground and does not disappear is subject to shevi'is, and so is the money received for it, but it is not subject to bi'ur, and neither is its money, since bi'ur was stated only regarding things whose season passes and which are no longer found in the field. The Mishnah lists the examples - the root of the wild luf, the root of the dandanah, akarvanin, chalbitzin and buchriya, and from among the dye plants, puah and richpah. According to Rabbi Meir the money must be removed by Rosh Hashanah, and the Sages reject this with an a fortiori argument; the basis of Rabbi Meir's stringency with coins is that there is no way to recognize which coins are subject to bi'ur and which are not.