(Baraisa) (R. Oshiyah): If a person separated from one field to another, it is not valid - this should apply even to a Meitzar (see above Zevachim 17).

(R. Yosi bar Chaninah): Chatzav divides for Peah. (Chatzav is a plant that is often used to define the borders of a field.) R. Chisda said that this was used by Yehoshua bin Nun to divide the Land. And R. Chanina said a slightly different expression from Rav Chisda that it was used by Yehoshua to demarcate (the sections of the different tribes within) the Land.

A narrow stream is only considered a division if it has a flow of water, but if dry, it does not divide. But a river divides even if it is currently dried up.

Question: If our Mishnah (daf 17-1(a)) teaches that a private road divides, why does it then need to say that a public road divides?

Answer: To teach that even a public road does not divide for a tree; only a fence divides.

Question: If the Mishnah taught that a private path divides, why does it need to teach that a public path divides?

Answer: To exclude a public path that is only used in the summer but not in the rainy season.

(Rav): The cases in the Mishnah of an uncultivated land and a plowed land divide (between two other fields) when they are the size of a Beis Rova (10.5 Amos X 10.5 Amos - which is 25m2 according to Rav Chaim Na'eh and around 36m2 according to the Chazon Ish). And if it is another species (as the Mishnah taught), even a small amount divides (as it looks like a different field).

(R. Yochanan): An uncultivated land, a plowed land and another species all divide when they are the size of three furrows (2 Amos).

Question: Does R. Yochanan disagree with Rav about another species? (It appears so, because Rav said that even a small amount divides and R. Yochanan said that it must be three wide rows.) No; when Rav said that even a small amount divides, he was referring to produce that is obligated in Peah, (but when the produce is not obligated in Peah, there must be a space of 3 furrows). R. Yochanan was discussing produce not obligated in Peah (so he said 3 furrows).

Question: But do they disagree about an uncultivated land and a plowed land? Does anyone say that those are obligated in Peah? Rather, Rav and R. Yochanan both agree that those only divide when they are a Beis Rova wide. However, when Rav said Beis Rova, he was referring to a square field, such as 20X20 Amos, in order to divide. And R. Yochanan was referring to a field that is 50 X 2 Amos (which is 100 Amos2).

(R. Zeira citing R. Elazar): R. Meir and R. Yehuda both said the same concept - just as R. Meir said that if one harvests for animal fodder, it is not called the beginning of harvesting and therefore divides the field; so R. Yehuda also says the same thing. And just as R. Meir says that Peah (that did not need to be taken) is a division, so R. Yehuda also says that same thing.

Question: Where do we find that R. Meir reasons that only something that is obligated in Peah divides? As the Baraisa teaches - if the produce in the middle of the field was consumed by locusts or ants, if the wind or an animal broke it, all agree that if he plowed there, it divides; if not, it does not divide.

Who is 'all agree'? Isn't it R. Meir, who said that the crops there are exempt from Peah, so they do not divide. However, if they are obligated (such as if they were harvested for animal fodder), they divide and the field is obligated in two Peahs. (But here, it is referring to harvesting after it had grown 1/3rd of its growth, so it is obligated in Peah) even if he did not plough.

It is as we have learned (in Maseches Menachos Perek 6, that it is permitted to harvest for animal fodder even before the Omer offering is brought). And R. Yehuda said that this is true, as long as the crops had not grown 1/3rd of their growth. Once they grew 1/3rd, he must give Peah from them. (In conclusion, R. Eliezer agrees with R. Meir that) something that is obligated in Peah divides.

Question (R. Zeira): (Against R. Elazar that he cited above (l)) - this is like the opinion of R. Yehuda (in Menachos above) that if it is discussing when harvested before it grew 1/3rd. How did R. Elazar know to connect them - perhaps R. Yehuda would say that harvesting for animal fodder, even if it had already grown 1/3rd, would be exempt from Leket, Shichechah and Peah? (And if this is correct, R. Meir in the Mishnah would not only be speaking about after it grew 1/3rd.)

Rather, perhaps R. Meir said that if he began harvesting before it had grown 1/3rd, even if he finished after it had grown 1/3rd, it is exempt from Peah. Alternatively, he said that anything harvested before is exempt and anything harvested after 1/3rd is obligated...? The Gemara does not resolve this doubt about R. Meir's opinion.