Is a bequest concerning the usufruct (fruit, yield, or service) of property valid?

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The bequest of the fruit of a tree, an orchard, the yield of a house, or the service of a slave is valid. This ruling applies whether the bequest specifies a known period or covers all the fruit and benefit for the entire duration. This is the opinion of the majority (Al-Jumhur), including Malik, Al-Thawri, Al-Shafi'i, Ishaq, Abu Thawr, and the Ashab al-Ra'y (Hanafi school). The evidence supporting this is that the ownership of such usufruct is valid through a contract of exchange (mu'awada), thus the bequest of it is valid, similar to bequests of tangible assets. Furthermore, this bequest must originate from the testator's one-third disposable estate (thuluth). If it exceeds the one-third limit, it is executed only to the extent of one-third of the value.