Kilayim, Chapter 3, Mishnah 7. This Mishnah continues the discussion of the unique considerations that come into play when dealing with a gourd, which has distinctive characteristics of its own. Our Mishnah actually stands in contrast to the Mishnah in Chapter 2, Mishnah 10, where we learned that vegetables next to vegetables - when one plants one vegetable alongside another vegetable - a separation of six tefachim is enough, whereas grain next to vegetables or vegetables next to grain, in whichever direction it may be, requires a beis rova: ten amos and a bit by ten amos and a bit.
"Dela'as b'yarak" and "dela'as b'tevuah":
The Mishnah rules that "dela'as b'yarak" - a gourd planted in a field of vegetables - has the status of a vegetable, and its law is identical to what we saw in Chapter 2, Mishnah 10, regarding one who plants a vegetable alongside a vegetable: six tefachim. But when one plants a gourd in a field of grain, "u'v'tevuah - k'tevuah, shenosnin lah beis rova" - and in grain it is treated as grain, for we give it a beis rova: they must be separated by a beis rova, ten amos and a bit by ten amos and a bit.
A row of gourds:
"Haysah sadeihu zarua tevuah, u'vikesh litoa l'sochah shurah shel dela'in" - his field was sown with grain, and the owner of the field wishes to plant in it not a single gourd but an entire row of gourds - "nosnin lah la'avodasah shishah tefachim" - we give it six tefachim for its working space, and that is enough. The Tosefta notes that the measure of six tefachim was stated regarding the width, but along the length one must maintain a separation of six tefachim across approximately ten and a half amos. In any case, the required width is only six tefachim.
At first glance this is puzzling: for a single gourd a beis rova is required in both directions, and for an entire row of gourds six tefachim is enough? The reason is that a single gourd looks as though it is mixed in among the other plants, whereas an entire row is a distinct entity, and that distinctness prevents the appearance of kilayim.
The Mishnah does, however, add a qualification: "v'im higdilah - ya'akor milfaneha" - and if it grew larger, he should uproot in front of it. If the gourd spread out too much, one must uproot the plants in front of it and make sure that it does not overstep the boundaries that were set.
The opinion of Rabbi Yosi:
Rabbi Yosi disagrees and holds: "nosen lah avodasah arba amos" - he gives it four amos as its working space. Even for an entire row of gourds one may not suffice with six tefachim, and a separation of four amos is required. A beis rova is not needed, but at least four amos are. To this the Sages responded: "v'zeh chamur min hagefen?" - and is this more stringent than a vine? Should the law of a gourd be more stringent even than the law of a vine?
The vine is a subject we will deal with shortly, when we begin the laws of kilei hakerem. Kilei hakerem is more severe than the laws of kilei zera'im: kilei zera'im is the prohibition we have learned until now, sowing different species of vegetables together; but one who sows a vegetable in a vineyard renders the produce forbidden to benefit from, and no use may be derived from it. That is an added severity. And yet regarding a vine the law is that even for a row of five full-grown vines six tefachim is enough, as we will see later on, at least according to Beis Hillel. Why then should a row of gourds be more stringent than a row of vines?
To this "amar lahen: matzinu shezu chamurah min hagefen" - he said to them: we have already found that this is more stringent than a vine:
A single vine: "nosen lah avodasah shishah tefachim" - he gives it six tefachim as its working space, and according to all opinions six tefachim is enough.
A single gourd: "nosen lah beis rova" - he gives it a beis rova, as stated at the beginning of the Mishnah, a full measure of ten amos and a bit in every direction.
From here we see that we treat a gourd with added stringency, and therefore Rabbi Yosi holds that even a row of gourds - which ordinarily is not governed by the stricter law - requires four amos.
Additional stringent opinions:
From here on the Mishnah brings especially stringent opinions in matters of kilayim:
Rabbi Meir in the name of Rabbi Shmuel: "kol sheloshah dela'in l'veis se'ah - lo yavi zera l'soch beis se'ah" - wherever there are three gourds in a beis se'ah, he may not bring seed into that beis se'ah. A beis se'ah is a large area, fifty amos by fifty amos; and even so, once three gourds have been planted in it, one may not bring into it seed of another species, since the area of a beis se'ah is not considered sufficient. Working out the numbers, this comes to a third of a beis se'ah for each gourd - a very large area.
Rabbi Yosi ben HaChotef Efrasi in the name of Rabbi Yishmael: he was even more stringent. Even when there are only three gourds, one may not bring seed into an area of thirty se'ah - an enormous area, and it too is forbidden.
It is worth noting that the Rashbam clarifies that this is not speaking about an ordinary gourd, but about a Greek gourd, whose leaves are especially long and which spread into and become intermingled with other plants; but with the other types of gourd these laws do not apply.
In summary: in this Mishnah we learned that a gourd among vegetables is treated as a vegetable - six tefachim, and among grain it is treated as grain - a beis rova; whereas an entire row of gourds in a grain field suffices with six tefachim, because it is a distinct entity, provided that it does not grow and overstep its bounds. Rabbi Yosi requires four amos even for a row, based on the stringency we found regarding a single gourd as compared with a single vine, and the Sages responded that a gourd should not be treated more stringently than a vine. Finally, even more stringent opinions were brought in the name of Rabbi Shmuel and in the name of Rabbi Yishmael, along with the words of the Rashbam that all of this was said specifically about a Greek gourd.