Shemittah with regard to mushrooms

[1] (halacha 9)

Question: Do the laws of Shmittah apply to mushrooms?

Answer: It is ruled in the Shulchan Aruch (Shulchan Aruch Admur HaZakein siman 204 se'if 1, and Seder Birchas HaNehenin chapter 7 se'if 1) that the bracha over mushrooms is not "Borei Pri HaAdamah" but rather "Shehakol Nihyeh Bidvaro," since even though they grow from the ground - from the moisture of the ground, they nevertheless do not draw nourishment from the ground - from the earth, but rather from the air. Therefore terumos and ma'asros do not apply to mushrooms. Based on this, the poskim wrote that for the same reason the sanctity of Shevi'is does not apply to them (Shu"t Minchas Yitzchak 8:99. Yalkut Yosef Shevi'is 15:3) and this is the essential halacha. (However, nowadays that mushrooms are grown in greenhouses in an organized manner, there are those who wished to be precise and stringent to apply the sanctity of Shevi'is to mushrooms).

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