3,391. Completing the Labor of Produce
Hilchos Maaser 3:7
If someone completes the requisite labor for someone else’s produce without the owner’s knowledge, or if the other person brings about one of the six causes that render produce obligated in tithes without the owner’s knowledge, the produce in question must be tithed.
Hilchos Maaser 3:8
Completing the requisite labor means, for example, rubbing gourds, squash and watermelon to remove the golden hairs from them. If he doesn’t rub them, then it’s when he makes a pile of them, or in the case of watermelon, when he organizes them one next to another in their designated place. If a person rubs fruits one at a time, that species’ labor is considered finished when he finishes rubbing them. Terumah may be taken from gourds and squash even if the hairs have not been removed.