Related for Demai 1:10

These are the leniencies with Demai (uncertainly tithed produce): wild figs, the fruit of the lotus, and azerole are presumed exempt in every place (cf. Dem. 1:1). But if they were watched over, they are liable [as Demai]. If [they happen to also be watched over by virtue of] someone protecting his field (i.e, where they happen to have grown), they are exempt. Rabbi Yosei says, wild figs from Tzipporin are liable [as Demai] because they are watched over. Rabbi Yosei son of Rabbi Yehudah says, unripe dates that are sold along with [ripe] dates are liable. And the sages say, until they begin to ripen [lit. "to leaven"] they are exempt, [but] from [the time that] they begin to ripen they are liable.

[Produce purchased in] Cheziv [=Achziv, a town in northern Israel] alone is exempt from Demai (cf. Dem. 1:3). [But] the presumption is that [produce purchased elsewhere in] the Land of Israel is liable, unless it is known [with certainty] that it is exempt. [Conversely] the presumption is that [produced purchased] outside the Land of Israel is exempt until it is known [with certainty] that it is liable. [One who purchases produce from] Israelite landowners [who are presently residing] in Syria need not separate Demai [for the purpose of tithing], but if it is known that the majority of the produce is theirs (i.e., grown on their land in Israel), behold, it is liable.

One who buys flour for [tanning] animal hides is exempt from Demai (cf. Dem. 1:3) but liable as to certainly untithed [produce]. And with [respect to] certainly untithed [flour] that he used on animal hides, he is permitted to [continue] using it on other animal hides.

[With respect to] spiced oils (i.e., aromatics made with spices typically subject to tithing), Bet Shammai holds [the mixture] liable and Bet Hillel exempts it (cf. Dem. 1:3). Rabbi Nathan said, "Bet Hillel did not exempt [tithing spiced oils] except as to balsam oil." Others say in the name of Rabbi Natan, "Bet Hillel rendered liable rose oil." [With respect to] replacements for heave offerings, or repayments of the value [of the produce] plus a fifth (i.e., the payment for which someone who consumes Terumah unwittingly is liable, see Ter. 6:1), or the surplus of the omer [offered on the 16th of Nissan], or the two loaves [from the new wheat offered on Shavuot], or the showbreads, or the leftovers of the grain offerings [after the priests have offered the required handful]" (see Bava Kamma 110b:14), Rabbi Shimon ben Yehudah says in the name of Rabbi Shimon, "Bet Shammai rendered liable and Bet Hillel exempted [these agricultural gifts]." And anyone who designates [any of these agricultural gifts] for second tithe, what he has done is done (i.e., there is no punishment but the sages do not approve).