of falling leaves, or over the frame of a four-post bed. One may spread a sheet, however, over the frame of a two-post bed. It is not valid to train a vine, gourd, or ivy to cover a sukkah and then cover it with sukkah covering (s'chach). If, however, the sukkah-covering exceeds the vine, gourd, or ivy in quantity, or if the vine, gourd, or ivy is detached, it is valid. The general rule is that one may not use for sukkah-covering anything that is susceptible to ritual impurity (tumah) or that does not grow from the soil. But one may use for sukkah-covering anything not susceptible to ritual impurity that grows from the soil. Bundles of straw, wood, or brushwood may not serve as sukkah-covering. But any of them, if they are untied, are valid. All materials are valid for the walls. Rabbi Judah taught that one may use planks for the sukkah-covering, but Rabbi Meir taught that one may not. The Mishnah taught that it is valid to place a plank four handbreadths wide over the sukkah, provided that one does not sleep under it. The Mishnah taught that a stolen or a withered palm-branch is invalid to fulfill the commandment of . If its top is broken off or its leaves detached from the stem, it is invalid. If its leaves are merely spread apart but still joined to the stem at their roots, it is valid. Rabbi Judah taught that in that case, one should tie the leaves at the top. A palm-branch that is three handbreadths in length, long enough to wave, is valid. The Gemara explained that a withered palm branch fails to meets the requirement of because it is not (in the term of ) "goodly." Rabbi Johanan taught in the name of Rabbi Simeon ben Yohai that a stolen palm-branch is unfit because use of it would be a precept fulfilled through a transgression, which is forbidden. Rabbi Ammi also stated that a withered palm-branch is invalid because it is not in the word of "goodly," and a stolen one is invalid because it constitutes a precept fulfilled through a transgression. Similarly, the Mishnah taught that a stolen or withered myrtle is not valid. If its tip is broken off, or its leaves are severed, or its berries are more numerous than its leaves, it is invalid. But if one picks off