Reference for Kilayim 6:5

אֵיזֶהוּ אִילַן סְרָק. כָּל שֶׁאֵינוֹ עוֹשֶׂה פֵרוֹת. רַבִּי מֵאִיר אוֹמֵר, הַכֹּל אִילַן סְרָק, חוּץ מִן הַזַּיִת וְהַתְּאֵנָה. רַבִּי יוֹסֵי אוֹמֵר, כָּל שֶׁאֵין כָּמוֹהוּ נוֹטְעִין שָׂדוֹת שְׁלֵמוֹת, הֲרֵי זֶה אִילַן סְרָק:

What is a <i>serak</i> tree? Any tree that does not bear fruit. Rabbi Meir says, [regarding vine trellising] all trees are [considered] <i>serak</i> trees [because they are regarded as insignificant in view of the vine], except the olive [tree] and the fig [tree]. Rabbi Yosi says, All trees the like of which are not normally planted exclusively as whole fields, are <i>serak</i> trees.

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