In the Torah there is an obligation to leave the corner of one's field of grain. That is called Peah. The Yerushalmi [The Gemara written in Israel], asks what if the first stalk that is cut was then burned. Rav Shach [Laws of Peah 2:11] explains this question to be based on a previous doubt of the Gemara if the first stalk that was harvested can be made into peah. The Gemara itself answers thus: Since it makes other talks obligated, it itself can not be obligated.
So the order of the Gemara would have to be thus: Can the first stalk be made into peah? And if you say yes then if it is burned then does one have to reap another stalk for the field to be obligated in peah. Then the Gemara answers the first question in the negative. That stalk can not become peah. So automatically we know the answer to the second question.
I can see the idea of the Gemara's question what if the first stalk is burned? You can find something like this in reading the Megilah."One who is obligated can cause others to fulfill their obligation." That is what it seems the Gemara must mean. but on the other side of thing you can say lets say Grace After Meals for the sake of someone who has eaten bread though you have not.. But at any rate, you can see the question of the Gemara. If that first stalk causes the obligation then if it is burned you would need to reap a new stalk..
There are definitions here. Poor means someone with no money a period of time. Poor does not mean anyone asking for money. In fact the Rambam has a long essay about the evil of the heads of the yeshivot that ask for charity in Pirkei Avot perek 4 mishna 3.
