'Tree' in the Bible

Now if some of the branches were broken off, and you, [although you] were a wild olive tree, were grafted in among them and became a sharer of the root of the olive tree's richness,

For if you were cut off from what is by nature a wild olive tree, and contrary to nature were grafted into a cultivated olive tree, how much more will these who are {natural branches} be grafted into their own olive tree?