Reference for Chullin 271:62

ישראל שלקח שדה בסוריא מעובד כוכבים עד שלא הביאה שליש חייב משהביאה שליש ר"ע מחייב בתוספת וחכמים פוטרין

from a gentile before the produce had reached a third of its growth, it is subject [to tithe]; if it had already reached a third of its growth,<span class="x" onmousemove="('comment',' At which stage corn becomes liable to tithe, cf. Ma'as. I, 3.');">⁴⁴</span>

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