Reference for Bava Batra 164:16
א"ל אנא לא ידענא אלא עובדא הוה
— R. Joseph said in the name of Rab Judah in the name of Samuel: [A distance] of four to eight cubits [between any two trees]. Raba said in the name of R. Nahman in the name of Samuel: From eight to sixteen [cubits]. Abaye said to R. Joseph: Do not dispute with R. Nahman, for we learnt a Mishnah that is in agreement with him. For we learnt:<span class="x" onmousemove="('comment',' Kil. IV, 9. ');"><sup>26</sup></span> He who plants his vineyard [and leaves distances of] sixteen cubits [between the rows] may insert seed there.<span class="x" onmousemove="('comment',' Between the rows. Because the wide spaces between the rows are not regarded as part of the vineyard where, in accordance with Deut. XXII, 9, seed must not be sown. ');"><sup>27</sup></span> R. Judah said: It occurred in Zalmon<span class="x" onmousemove="('comment',' A locality near Shechem. ');"><sup>28</sup></span> that one planted his vineyard, [leaving distances of] sixteen cubits [between the rows], and turned the branches of [every] two [adjacent] rows towards one side,<span class="x" onmousemove="('comment',' Away from the space between them; thus leaving, between every alternate pair of rows, a clearing of sixteen cubits in width. ');"><sup>29</sup></span> and sowed the clearing. In the following year he turned the branches towards the spot sown [in the previous year], and sowed the uncultivated [spaces].<span class="x" onmousemove="('comment',' Which in the previous year could not be sown on account of the branches which were encroaching on the required space of sixteen cubits. ');"><sup>30</sup></span> When the matter was reported to the Sages they allowed it.<span class="x" onmousemove="('comment',' Because the branches were turned away from the sown spaces which were sixteen cubits in extent. A space of less than sixteen cubits would have been regarded as part of the vineyard. This proves the correctness of R. Nahman's report that a space of sixteen cubits is required for a piece of ground to be regarded as a separate unit. ');"><sup>31</sup></span> He [R. Joseph] said unto him: I am not aware [of this]: but there was a case