Reference for Menachot 10:8
קוֹצְרִים בֵּית הַשְּׁלָחִים שֶׁבָּעֲמָקִים, אֲבָל לֹא גוֹדְשִׁין. אַנְשֵׁי יְרִיחוֹ קוֹצְרִין בִּרְצוֹן חֲכָמִים, וְגוֹדְשִׁין שֶׁלֹּא בִרְצוֹן חֲכָמִים, וְלֹא מִחוּ בְיָדָם חֲכָמִים. קוֹצֵר לַשַּׁחַת, וּמַאֲכִיל לַבְּהֵמָה. אָמַר רַבִּי יְהוּדָה, אֵימָתַי, בִּזְמַן שֶׁהִתְחִיל עַד שֶׁלֹּא הֵבִיאָה שְׁלִישׁ. רַבִּי שִׁמְעוֹן אוֹמֵר, אַף יִקְצֹר וְיַאֲכִיל אַף מִשֶּׁהֵבִיאָה שְׁלִישׁ:
They may reap in irrigated fields in the valley [before the <i>omer</i> is brought], but they may not stack it. The people of Jericho used to reap [before the <i>omer</i> was brought in accordance] with the will of the Sages, and used to stack it against the will of the Sages, but the Sages did not protest. One may reap hay to feed livestock; Rabbi Judah said: When is this so? If one had begun to reap it before it had brought forth a third [of its growth]. Rabbi Shimon says: one may even reap it and feed [his livestock with it] even after it has brought forth a third [of its growth].