Reference for Kilayim 4:6

הַנּוֹטֵעַ שְׁתַּיִם כְּנֶגֶד שְׁתַּיִם, וְאַחַת יוֹצְאָה זָנָב, הֲרֵי זֶה כֶרֶם. שְׁתַּיִם כְּנֶגֶד שְׁתַּיִם וְאַחַת בֵּינְתַיִם, אוֹ שְׁתַּיִם כְּנֶגֶד שְׁתַּיִם וְאַחַת בָּאֶמְצַע, אֵינוֹ כֶרֶם, עַד שֶׁיְּהוּ שְׁתַּיִם כְּנֶגֶד שְׁתַּיִם וְאַחַת יוֹצְאָה זָנָב:

If one plants two [vines] opposite two [vines] and one [vine] protrudes like a tail, it is [considered] a vineyard. [If one planted] two [vines] opposite two [vines] and one [vine] between [two of the vines], or two [vines] opposite two [vines], and one in the center, it is not [considered] a vineyard until there are two [vines] opposite two [vines] and one [vine] protrudes like a tail.

Jastrow

Jastrow