What compelled Rashi 7a 'mi-makon acheir' to explain that he was using the veggie in house to act as maasar on the entire BUNDLE in front of him instead of merely acting as maasar on the leaf alone - as after all he was eating only the leaf, not a whole bundle? Is it because the leaf alone would be too small of a shiur (less than prutah) upon which to separate maasar upon whereas the bundle would suffice in shiur?
DANIEL GRAY, TORONTO Canada
1) When one takes Ma'aser, he takes one tenth of the food placed in front of him and gives it to the Levi (let us assume we are discussing giving Ma'aser Rishon to the Levi). The leaf that Rebbi Meir ate was one of the leaves in the bundle (as the Gemara told us a few lines ago) and the vegetable was the Ma'aser. This means there would be ten times as much food in the bundle than the quantity of the vegetable. So even though one may only want to eat one leaf now, the normal practice is to take Ma'aser on the whole bundle, so that the entire bundle now becomes permitted to eat whenever one wants to do so. If Rashi would be telling us that he was using the vegetable to act as Ma'aser on the leaf alone, this would mean that the leaf would have to be ten times larger than the vegetable.
2) Generally speaking, there is no lower limit to the obligation to take Ma'aser.
a. The Talmud Yerushalmi (Terumos 11:4, just before Mishnah 5) tells us that if the Terumah is Tahor, then even for the smallest amount of Terumah one must look for the Kohen and give it to him. The Yerushalmi continues and elaborates that this applies only to Demai, because it may be that Ma'aser has already been separated, but if one is certain that Ma'aser has not been separated ("Vadai") then one has to go and look for the Kohen even to give the smallest amount of Terumah, even if it is Tamei.
b. However, the Rambam (Hilchos Terumos 3:16) writes that the above aplies only to wine and oil. The Kesef Mishneh explains that one may put the smallest amount of oil in one's candle. Similalry, it is worth it for the Kohen to receive a drop of wine, because this might be sufficient to strenghten his heart. In contrast, the Mishnah (Terumos 11:8) states that food of less than 1/64th of a "Log" gives no benefit, but even for this amount one must separate the Ma'aser and then one can throw it in the fire.
c. In short, even the smallest amount of food is liable for Ma'aser. In addition, it should be pointed out that the measure of a Perutah's worth is not a relevant guide. One of the reasons for this is that between the time of the Gemara and our time, there has been a tremendous rate of inflation. A Perutah at one time was worth a lot more. The SM'A (to Choshen Mishpat 88:2) writes that in the time of the Gemara, one could buy a lot of fruit for a Perutah. A better landmark might be an egg-size of food, because the Yerushalmi I cited above (Terumos 11:4) states that if the Terumah is Tahor one must give it to the Kohen even though it is Demai and is less than than a k'Beitzah.
Kol Tuv,
Dovid Bloom