- - Q. Kevod Horav Shlit’a . Is one allowed to walk on grown or long grass during Shabbat?
A. Poskim write Based on the prohibition of climbing a tree on Shabbat, it seems that walking on grass on Shabbat should likewise be forbidden, for this is similar to climbing a tree.
However, this is indeed not the case, for grass is not considered a tree and is merely a plant; Shulchan Aruch (O.H. 326: 3 rules that it is permitted to walk on herbs and grass on Shabbos, regardless if they are dry or not, since he has no intention of cutting them.
Mishna Berura (ibid. 24) rules that although it is still forbidden to perform any work on Shabbos even if one does not intend or wish to perform it, this only applies when we are certain that a forbidden work will be performed (P’sik Reisha).
Mishnah Berura (24 - 25) writes that when the grass or weeds are very tall, one should take care not to run on them on Shabbos, for doing so will certainly cause them to be plucked from the ground.
He adds that it is possible that one must take care not to walk on them briskly either.
Rabbi A. Bartfeld as revised by Horav Yaakov Hirschman, Horav Dovid Pam, Horav Aharon Miller, Horav Chanoch Ehrentreu and Horav Kalman Ochs Shlit’a