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Bava Basra, 18

BAVA BASRA 18 (25 Nisan) - dedicated by Sandy and Les Wiesel in memory of Les's father, Menachem Yehuda ben Avigdor Yosef Wiesel, who perished in the Holocaust.


QUESTION: The Gemara cites the Mishnah later (26a) which states that when there is a fence between the fields of two neighbors, each neighbor may plant his trees adjacent to the fence. Similarly, if one of the fields is a wheat field, the other neighbor may plant trees in his field adjacent to the fence, and there is no concern for Kela'im.

How does the fence prevent the Isur of Kela'im from occurring? The roots of the tree meet the roots of the wheat below the fence, and thus it should still be prohibited to plant both plants adjacent to each other, even if there is a fence separating them!


(a) TOSFOS later (19a, DH ha'Mavrich) proves from this Gemara that as long as the wheat and the fruit tree do not mingle *above* the ground, there is no Isur of Kela'im. Even if their roots mingle beneath the ground, the Isur of Kela'im applies only when the plants mingle above the ground. This also seems to be the approach of RASHI here (end of DH Geder).

(b) The RI MI'GASH writes that the Isur of Kela'im requires that two things be avoided: first, the roots of the two plants must not absorb their nourishment together, and, second, that the offshoots and branches of the two plants not mingle. The Mishnah that our Gemara quotes is referring to a case in which there is a large rock ("Tzunma") beneath the fence that prevents the roots of the plants from mingling. The fence between the two plants prevents their branches from mingling. (This view is also cited by the ME'IRI at the beginning of Bava Basra.)

The KOVETZ SHI'URIM points out that according to this explanation, when the Gemara in Eruvin (11b) says that the Halachic concepts of "Tzuras ha'Pesach" and "Gud Achis Mechitzasa" work to prevent the intermingling of branches of plants with regard to Kela'im, it must also be referring to when there is a large rock that separates between their roots, because a separation above the ground does not suffice according to the Ri mi'Gash.

(RAV SHLOMO ZALMAN AUERBACH zt'l in MINCHAS SHLOMO (end of #36) questions this explanation based on the Gemara later (19b), which says that when one replants a shoot of a grapevine, it is permitted to sow wheat seeds to the sides of the replanted shoot (but not directly over it), even within a distance of three Tefachim, even though the roots of the plants will be mixing. The Gemara there certainly cannot be referring to when there is a rock separating the roots, because the Gemara there is learning from that case that roots do not take root and spread out sideways.) (I. Alsheich)


QUESTION: The Gemara explains that the Rabanan hold that one who raises bees to produce honey can prevent his neighbor from planting a mustard plant near the boundary of their properties, because the mustard harms the bees -- the sharp taste of the mustard makes the bees eat their honey, and thus the owner loses his honey. The Gemara asks that, according to the Rabanan, why is the bee-owner not required to distance his bees from the boundary since, after all, they will harm the neighbor's mustard plant by eating it? The Gemara answers that bees do not cause damage to the mustard plant, because we are not concerned that they will eat the kernels, since it is very difficult for them to find the kernels, and we are not concerned for the damage that they do by eating the leaves, because the leaves will grow back.

How does this answer the question? The bees are still going to cause damage to the mustard plant, because when the leaves grow back, the bees will eat them again! Every time they grow back, the bees will eat them, and thus the mustard plant will never be able to grow properly! (RA'AVAD, cited by RAMBAN and RASHBA)


(a) The RA'AVAD answers that once the bees have eaten and tasted the mustard leaves once and have felt its sharpness, they will not eat it again. Therefore, the bee-owner is not required to prevent his bees from eating the mustard leaves, since the leaves will grow back and the bees will not eat them again. The owner of the mustard plant, on the other hand, must distance his plant, because even by eating the leaves only once, the bees will have a desire to eat their honey, and the bee-owner will suffer a loss as a result.

The RASHBA challenges this answer. First, the Gemara (end of 18a, in explaining the view of Rebbi Yosi) implies that the bees come constantly to eat the mustard plant ("Ba'os v'Ochlos"), and not that they just eat from it a single time and not more.

Second, the Gemara implies that the bees come and eat the mustard plant *now*, after it has been planted, and, nevertheless, the Rabanan require the owner to uproot his plant and plant it farther away from the boundary. According to the Ra'avad's explanation, why does the owner have to distance his plant? Once the bees have eaten from it the first time, they will not eat from it again, and the plant no longer causes any damage to the bees! According to the Ra'avad, the owner should be allowed to leave his plant adjacent to the boundary!

Third, the Rashba asks that according to the Ra'avad, the Rabanan's rejoinder to Rebbi Yosi is not clear. The Rabanan explain that the bees are not considered a Mazik to the mustard plant, because the leaves that they eat will grow back. Still, though, *before* the eat the leaves for the first time, the bees *are* considered a potential Mazik to the mustard plant! Moreover, once the bees have damaged the mustard plant by eating from it the first time (and the bees thereby suffer damage by having to eat their honey to subdue the sharp taste of the mustard), *neither* one will be damaging the other from now on! The bees will not eat any more leaves, as the Ra'avad asserts, and as a result of not eating any more mustard, the bees will not eat their honey!

(b) The RASHBA, therefore, gives a different answer to the question of the Ra'avad. One who grows a mustard plant picks its leaves as soon as they grow. Thus, the bees do not cause damage by eating the leaves because they are picked before the bees can eat them. Even though the bees might eat a little bit before the owner has a chance to pick them, that small amount of leaves that they eat is not considered a loss at all.

(c) The Rashba gives another explanation and says that the primary purpose of the leaves is to protect the kernels of mustard. Since the leaves grow back whenever the bees eat them, there is no damage caused to the main part of the mustard plant -- the kernels. Hence, even if the bees continuously eat the leaves as they grow back, they are not causing any damage to the main part of the mustard plant, because the leaves constantly grow back and protect the kernels. (I. Alsheich)

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