עצי סוכה אסורים כל שמונת ימי החג בין עצי דפנות בין עצי סכך (ואפי' קיסם לחצוץ בו שיניו אסור) (מהרי"ל) ואין נאותין מהן לדבר אחר כל שמונת הימים מפני שיום הז' כולו הסוכה מוקצה עד בין השמשו' והואיל והוקצה לבין השמשות של שביעי הוקצה לכל היום : הגה ואפי' נפלה הסוכה אסורים ולא מהני בה תנאי (טור) אבל עצים הסמוכים לסוכה מותרים וע"ל סי' תקי"ח סעיף ח': ואם אחר שעשה השיעור הצריך מן הדפנות ונשלם הכשר סוכה הוסיף דופן לא מיתסרא אבל אם עשה ארבעתן סתם כולן אסורות ומוקצות: הגה וכל זה לא מיירי אלא בסוכה שישב בה פעם א' אבל אם הזמינה לסוכה ולא ישב בה לא נאסרה דהזמנה לאו מילתא היא: (הגהות אשירי פ' המביא):

1.A Sukkah its Decorations are Forbidden [for Mundane Use] Throughout Seven [Days of Festival], 2 Seifim: It is forbidden to make use of the wood throughout the eight days of the festival, whether the pieces for the wall or the s'chach (and even a sliver to use as a toothpick is forbidden)(Maharil). They are not suitable for other things all eight days - because on the seventh day the sukkah itself is entirely muktzeh until twilight since if it is muktzeh for בין השמשות it is muktzeh for the whole day. RAMA: Even if the sukkah fell over it is forbidden, and a stipulation is never effective (Tur). But wood that covers the sukkah is permissible (to be used), see above Siman 518: Seif 8. And if after the minimum requirement for the size of the walls are met and the valid sukkah is complete, one adds a wall it is not forbidden. But if he only made four walls in total it is forbidden and is muktzeh.RAMA: And all of this only applies to a sukkah that one dwelt in one time. However, if one was invited to the sukkah but did not dwell there it is not forbidden, because the invitation is not the main thing (Hagahos Ashiri)

2. And similarly one may not use, during any of the 8 days, food and delicacies that are hung in the sukkah to beautify it, even if they fell *and on Yom Tov and Shabbos they are forbidden to move anyway because they are muktzeh (Tur).*If one stipulates about them at the time they are hung, and says "I will not refrain from making use of them throughout the time of bein hashmashos ( on all the eight days of the festival) (Beis Yosef), he can then make use of them at any time he wishes, because he did not make them muktzeh and the holiness of the sukkah does not rest on them. (This applies) specifically when he uses this language. If, however, one does not use the above wording when making his stipulation, but merely says, “I stipulate that I will be permitted to benefit from [the decorations] if they fall from the sukkah,” this stipulation is not effective at all. And (likewise) if one says, "I stipulate that I can eat them whenever I want if it is the twilight period between sunset and the appearance of three stars".RAMA: One must make the stipulation before בין השמשות of the first day. There are those Achronim who write that these days it is not our custom to stipulaye [Maharil] and this is how we act regarding the decorations hung from the s'chach. However, regarding the decorations that we place on the walls, for example decorated sheets, it is our custom to move them due to rain even without a stipulation, because there are those who say that it is not forbidden - even regarding the walls themselves; how much more so the decorations. In any event it is good to stipulate regarding them. If the s'chach is made of myrtle or one hangs an Etrog in the sukkah as a decoration it is permitted to smell it, because one does not violate the laws of muktzeh by smell, only by touching. They are forbidden to move. There are those who forbid the above related to a myrtle. [R"an, end of the chapter of the stolen Lulav] like below Siman 653.