Ma'aser Sheini2: 4
כַּרְשִׁינֵי מַעֲשֵׂר שֵׁנִי יֵאָכְלוּ צִמְחוֹנִים, וְנִכְנָסִים לִירוּשָׁלַיִם וְיוֹצְאִין. נִטְמְאוּ, רַבִּי טַרְפוֹן אוֹמֵר: יִתְחַלְּקוּ לְעִסּוֹת; וַחֲכָמִים אוֹמְרִים: יִפָּדוּ. וְשֶׁל תְּרוּמָה, בֵּית שַׁמַּאי אוֹמְרִים: שׁוֹרִין וְשָׁפִין בְּטָהֳרָה, וּמַאֲכִילִין בְּטֻמְאָה. וּבֵית הִלֵּל אוֹמְרִים: שׁוֹרִין בְּטָהֳרָה, וְשָׁפִין וּמַאֲכִילִין בְּטֻמְאָה. שַׁמַּאי אוֹמֵר: יֵאָכְלוּ צָרִיד. רַבִּי עֲקִיבָא אוֹמֵר: כָּל מַעֲשֵׂיהֶן בְּטֻמְאָה.
Bitter vetch of maaser sheni is eaten as shoots, and it may enter Jerusalem and leave. [If] it became tamei, R' Tarfon says: It is distributed into doughs; but the Sages say: It is redeemed. And [bitter vetch] of terumah, Beis Shammai say: We soak and pound it in taharah, but feed it in tumah. But Beis Hillel say: We soak it in taharah, but we pound and feed it in tumah. Shammai says: It is eaten dry. R' Akiva says: Everything done with it is [done] in tumah.
Ma'aser Sheini2: 5
מְעוֹת חֻלִּין וּמְעוֹת מַעֲשֵׂר שֵׁנִי שֶׁנִּתְפַּזְּרוּ, מַה שֶּׁלִּקֵּט, לִקֵּט לְמַעֲשֵׂר שֵׁנִי עַד שֶׁיַּשְׁלִים, וְהַשְּׁאָר חֻלִּין. אִם בָּלַל וְחָפַן, לְפִי חֶשְׁבּוֹן. זֶה הַכְּלָל: הַמִּתְלַקְּטִים לְמַעֲשֵׂר שֵׁנִי, וְהַנִּבְלָלִים לְפִי חֶשְׁבּוֹן.
Coins of chullin and coins of maaser sheni that became scattered, what he gathered, he gathered for maaser sheni until he completes [the total], and the rest is chullin. If [they fell in] a jumble and he scooped up handfuls, it is reckoned proportionately. This is the rule: What is picked up [one at a time goes] to maaser sheni, and what is jumbled is reckoned proportionately.