Is it permissible to benefit from animal carcasses (such as sheep and pigs) by placing them under trees (such as walnut and palm trees)? And what is the ruling on eating fruit from trees planted along the sides of cemeteries if passersby eat it for free, and what is the ruling on planting these trees in the first place?

The carcass of an animal is definitively impure by consensus, and fertilizing with it is a matter of scholarly disagreement: The Malikis and Shafi'is hold that crops irrigated with it become pure after washing (with the exception of the excrement of dogs and pigs). The Hanafis permit it. The Hanbalis, however, deem crops and fruits fertilized with it to be forbidden. It has been favored that using impure fertilizer is permissible, though disliked.

As for planting trees in graveyards: - If it is for ornamentation: This deviates the graveyards from their prescribed Islamic purpose of visitation and turns them into a place of ostentation. Furthermore, endowing property for the ornamentation of graveyards is invalid. - If it is for shade or fruit: No explicit prohibition has been reported, but it was not a practice during the preferred generations, and it might lead to walking or sitting on graves, which is forbidden. - Imitating Christians: Planting trees in graveyards is a common practice among Christians, and it involves imitating them, which is forbidden. - Graveyards are a place for admonition and reflection, not for tourism and entertainment.