They may not plant vegetables in a trunk of a sycamore tree. They may not graft rue on white cassia, since that is [grafting] a vegetable on a tree. They may not plant a young fig-shoot in sea squill so that it might provide shade for it. They may not insert a vine branch into a melon, in order that the latter might shoot its moisture to the former, since that is [grafting] a tree on a vegetable. They may not place gourd seed into anchusa for the purpose of preserving it (the gourd seed), since that is [grafting] a vegetable on another vegetable.