Reference for Maasrot 3:1

הַמַּעֲבִיר תְּאֵנִים בַּחֲצֵרוֹ לִקְצוֹת, בָּנָיו וּבְנֵי בֵיתוֹ אוֹכְלִין וּפְטוּרִין. הַפּוֹעֲלִים שֶׁעִמּוֹ, בִּזְמַן שֶׁאֵין לָהֶם עָלָיו מְזוֹנוֹת, אוֹכְלִין וּפְטוּרִין. אֲבָל אִם יֶשׁ לָהֶם עָלָיו מְזוֹנוֹת, הֲרֵי אֵלּוּ לֹא יֹאכֵלוּ:

One who was taking figs through his courtyard to be dried, his children and the members of his household may eat [of them] and are exempt [from tithing]. The workers that are [working] with him, when they are not owed food by him, may eat and are exempt. But if they are owed food by him, these may not eat.

Jastrow