Q. I have a portion of “mechitzos” on the cottage eruv, that are made from trimmed shrubs that are more than ten tefachim high and are over a foot wide. Though, when the wind blows, the branches and leafs shake, depending on the strength of the wind. Could these be used for “mechitzos”?

A. Mishna Berura (362,7) mentions that if a mechitza, made of plants, is invalidated if it sways with a common gust of wind. However, Horav Shlomo Miller Shlit”a points that firm established shrubs, that reach and are well attached to the ground, if only shake lightly are considered a proper wall. He quoted Chazon Ish (O.C. 77,6) that movement up to three tefachim (aprox. 30 cm.) is permitted. Aruch Hashulchan (362,8) cites a similar
opinion.

Tosefes Shabbos (ibid. 12) writes that we are more lenient on Shabbos mechitzos, than the ones employed in a Suka, as the former are needed only for a single day.

Rabbi A. Bartfeld as revised by Horav Shlomo Miller Shlit”a