1)

(a)Rebbi Yochanan ultimately learns the specifications of Sechach - from the Pasuk in Re'eh "b'Ospecha mi'Gornecha u'mi'Yikvecha", which means that the Sukah must be made of the waste products from the granary and from the wine-press - i.e. the stalks etc. of the one, and the branches and foliage from the other (commodities that are subject to Tum'ah and that grow from the ground).

(b)Rebbi Zeira initially explained that the Pasuk cannot be referring to the actual contents of the granary and the wine-press themselves - because "Yekev" means wine, and one cannot make Sechach out of wine.

(c)Rebbi Yirmeyahu however rejected Rebbi Zeira's Kashya - by suggesting that the Pasuk refers to congealed wine that comes from Snir (alias Mount Chermon - see Devarim 3:9), which resembled cakes of dried figs, and which could be used as Sechach.

(d)When Rebbi Zeira heard Rebbi Yirmeyahu's Kashya, he commented - that we had it so nicely worked out, until along came Rebbi Zeira and threw a spanner in the wheel.

2)

(a)Rav Ashi derived the specifications of Sukah from the very words ("mi'Gornecha u'mi'Yikvecha") themselves - implying the (waste) from the granary and from the wine-press, but not the wheat and the wine themselves.

(b)Rav Chisda learns them from the Pasuk in Nechemyah "Tzei'u ha'Har v'Havi'u Alei Zayis ... ", which goes on to list various materials, all of which comply with the given specifications for Sechach.

(c)Nechemyah included in his list both "Etz Avos" and "Alei Hadas" - which refer respectively, to Kasher Hadasim for their Lulavim, and Pasul ones (known as 'Hadas Shoteh') for their Sukos.

3)

(a)Our Mishnah disqualifies bundles of straw, wood or canes for use as Sechach - they do however, become Kasher, if one unties them (even after they are already on the roof of the Sukah - seeing as they are only forbidden because of a decree, and are not intrinsically Pasul).

(b)Using them (or any other material for that matter) as walls of the Sukah however - is permitted.

(c)Rebbi Yakov heard from Rebbi Yochanan the reasons for two Pesulim, one of them was that of our Mishnah, the other - the Pesul of scratching out a Sukah in a haystack (as stated in the Mishnah later in the Perek).

(d)Rebbi Yakov could not recall which of the two possible reasons, (one d'Oraisa and the other d'Rabanan) for these prohibitions, applied to which case. One of the reasons is 'because of Gezeiras Otzar' (that one might go on from there to use piles of materials from one's warehouse that were placed on the roof for storage, and not for shade); The other one is - 'Ta'aseh v'Lo min he'Asuy' (mid'Rabanan and mid'Oraisa respectively.

4)

(a)Rebbi Yakov had not however, heard what Rebbi Chiya bar Aba said in the name of Rebbi Yochanan, who explained that our Mishnah forbids using bundles of straw ... - for fear that someone arriving home from the field with bundles of straw might place them on the roof to dry, and then change his mind to use them as Sechach ('Gezeiras Otzar').

(b)In which case, the reason for invalidating a Sukah that is burrowed out of a hay-stack must be - because of 'Ta'aseh v'Lo min he'Asuy'.

(c)Rav Ashi queries Rebbi Yochanan however - on the grounds that seeing as both Ta'aseh v'Lo min he'Asuy' and Gezeiras Otzar apply to both cases, how does he know that the one reason applies to the one, and the other, to the other? Perhaps they are both Asur min ha'Torah, or perhaps they are both Asur mid'Rabanan!?

5)

(a)We reply that Rebbi Yochanan derives his distinction from the Lashon of the Tana in each case - because our Tana says 'Ein Mesach'chin Bahen' (implying Asur l'Chatchilah, but Kasher bedi'Eved - implying that it is only Asur mid'Rabanan); whereas with regard to a Sukah in a haystack, the Tana says 'Einah Sukah' (implying even bedi'Eved, it is not a Sukah, in which case it must be an Isur d'Oraisa).

(b)What makes ...

1. ... 'Chavilei Kash ... ' Kasher min ha'Torah - is the fact that the bundles were initially placed on the Sukah l'Shem Sechach.

2. ... 'ha'Chotet b'Gadish' Pasul - because the Sechach was not shaken l'Shem Sechach.

(c)In the latter case, would the Sukah be Kasher if the Sechach had been shaken - because once one does something positive to make the Sukah Kasher, people are unlikely to learn from there to use Pasul Sechach the next time (in which case even a decree mid'Rabanan is not applicable).

6)

(a)Rav Yehudah Amar Rav discusses 'male' and 'female' arrows. 'Male' arrows - comprises the pointed head of a wooden arrow which screws into the 'female' shaft.

(b)The former are Kasher for Sechach - because wooden objects that are not made in the form of a receptacle (that can hold liquid) are not subject to Tum'ah (and may therefore be used as Sechach); whereas the latter are Pasul - because, since they are made ion the form of a receptacle, they are subject to Tum'ah, (and is therefore Pasul).

(c)Rav Yehudah found it necessary to teach us that ...

1. ... male arrows are Kasher as Sechach - because we would otherwise have thought that Chazal would have decreed male arrows because of female ones.

2. ... female arrows are Pasul - because we would otherwise have thought that a receptacle that is made to be permanently filled, is not called a receptacle.

7)

(a)Flax stalks need first to be soaked and then pounded in the mortar - combed and bleached, before they are cut into threads.

(b)With regard to Sechach, Rabah bar bar Chanah quoting Rebbi Yochanan ...

1. ... invalidates 'Anitzei Pishtan' - the strands of flax after they have been combed.

2. ... validates 'Hutznei Pishtan' - the bundles of flax before they have even been soaked.

(c)Rebbi Yochanan himself is uncertain whether 'Hushni Pishtan' are valid as Sechach or not.

(d)Rabah bar bar Chanah is uncertain as to what constitutes Rebbi Yochanan's Safek, whether Hushni constitutes the bundles of flax between the pounding and the combing (whereas between the soaking and the pounding, they are still called 'Hutzni' and are Kasher for Sechach) - or whether, once they have been soaked, they are already called Hushni and are included in Rebbi Yochanan's Safek.

8)

(a)Rav Yehudah permits fern and Shivtzeri (a herb by the name of artemesia) to be used as Sechach. Abaye disagrees in the case of the latter - on the grounds that it has a repugnant smell that will cause a person to leave the Sukah, so Chazal issued a decree forbidding its use.