- דבר שיש לו מתירין and a distinction by shemittah mixtures
The Gemara attempts to bring a proof that growths do not have the halachah of their roots, from a Baraisa, in which Rebbe Shimon taught that any דבר שיש לו מתירין – prohibited item which has a method to permit it (such as tevel, which can be permitted through tithing) forbids a mixture with even a minimal amount. But items which cannot become permitted (such as terumah) all have proportions by which their mixtures would be permitted. Rebbe Shimon made a distinction regarding shemittah growths: Regarding ביעור – removal, meaning consuming shemittah produce before it must be removed from the house, it is a דבר שיש לו מתירין (because it can be eaten) and forbids a mixture with any amount. But regarding eating what became mixed after the time of bi’ur, when it is forbidden to eat, then only enough shemittah produce to give flavor in the mixture is forbidden. This includes a “mixture” of growths, such as a sixth-year (permitted) onion which was replanted and grew in shemittah. We see, then, that the growths during shemittah are forbidden, and are not extensions of the permitted root!? The Gemara answers that ordinarily, growths have the same halachah as the root, and any growths of a forbidden root are likewise forbidden. In the reverse case, where the permitted root would permit its growths, the Rabbis were stringent not to allow it the leniencies of the root.
- Prunings of chasayos of shemittah growing in the eighth year
The Gemara brings a proof from another Baraisa: Rebbe Shimon ben Elazar said about one pruning chasayos (a type of vegetable, defined later as those whose roots do not decompose, such as garlic or onions): אם ישראל חשוד על השביעית – If he is pruning with a Jew who is suspected about shemittah observance, and thus needs to consider the possibility that the chasayos are shemittah produce replanted, למוצאי שביעית מותר – what he prunes in the year after shemittah is permitted, because the (possibly) forbidden root has been sufficiently exceeded by the eighth-year growths. This demonstrates that permitted growths nullify the forbidden root (and are not forbidden themselves). The Gemara asks: ודלמא במדוכנין – Perhaps it is speaking of crushed chasayos. Since they were crushed before planting, they would not be significant enough to forbid their growths. The Gemara answers that the Baraisa is discussing someone suspected about shemittah observance, who would not bother to crush the chasayos to avoid the shemittah prohibition of the growths. [Permitting the growths is the sole purpose of crushing the chasayos before planting them.]
- שניא שביעית, הואיל ואיסורה ע"י קרקע בטילתה נמי ע"י קרקע
Having proven that shemittah growths are permitted, the Gemara asks that this should refute the opinions of Rebbe Yochanan and Rebbe Yonasan, who said otherwise on the previous Daf (by orlah and kilayim). The Gemara answers: שניא שביעית, הואיל ואיסורה ע"י קרקע, בטילתה נמי ע"י קרקע – Shemittah is different, because since its prohibition is a result of the ground (which imparts shemittah status), its nullification happens through the ground (by the growths of the non-shemittah year). Orlah, on the other hand, is forbidden because of the tree’s insufficient age, and kilayim is forbidden because of the forbidden mixture. The Gemara asks that by maaser, whose tevel prohibition is a result of its growing in the ground, we find that tevel produce which is replanted in shemittah (whose growths are hefker and exempt from tithing) does not lose its tevel status. The Gemara explains that the ma’aser obligation actually does not stem from its growing in the ground, but from its completion by דיגון – becoming finished grain (through piling).