משנה על סוטה 8:2

Rabbi Judah says: this is nothing but the fence of the vineyard fence. What then is a mehol of a vineyard? [A space] between two vineyards. What is considered a fence? One that is ten handbreadths high. And what is considered a trench? One ten handbreadths deep and four wide.

If a seah of terumah fell into a hundred [of hullin], and they were ground together and reduced in bulk, just as the hullin was reduced so too the terumah was reduced, and it is permitted. If a seah of terumah fell into less than a hundred [of hullin] and they were ground together and increased in bulk, just as the hullin became more, so too the terumah became more, and it is forbidden. If it is known that the kernels of hullin were better than the terumah, it is permitted. If a seah of terumah fell into less than a hundred [of hullin], and more hullin fell in afterwards, if it was accidental it is permissible, but if intentional it is forbidden.

Gaps in an aris must be eight cubits and somewhat more [in order to be able to sow seeds in the gaps]. [In the case of] all measurements that the sages said in connection with a vineyard, there is no ‘and somewhat more’, except in the case of gaps in an aris. The following count as gaps in an aris: if an aris was razed in its middle and five vines remained on one side and five vines on the other side. Then if the gap is [only] eight cubits, one may not bring seed there. [But if the gap is] eight cubits and somewhat more, they give [the vines] space to work them, and he may sow the rest.