In the tree/on the tree

There is a bird in the tree.

There are apples on the tree.

My gf’s school tested their kids on these differences. What the hell?

She says that it was explained to her that the bird comes from outside the tree so it’s in the tree. Apples come from the tree so they are on the tree?

Is this correct?

I guess the apples are part of the tree hence they are on the tree?

You can hang your coat on a small tree, or somewhere in a larger one. Christmas tree decorations come from outside but are still on it. Same for bugs on the leaves.

I think on is for things that adorn the outside, such as leaves or fruit, or wayward toilet rolls. In is for when you penetrate the outside covering and get amongst the branches. Think of a tree house surrounded by leaves compared to one built on the top after lopping the thins branches and trunk off.

Exactly. Her teacher is wrong (or her interpretation of what the teacher said). The distinction may not always be clear and some things could go one way or the other, but I agree with Loretta.

A bird sits on the branch of the tree.

There is a fungus growing on the tree.

A gentle light is shining on the tree.

My jacket is hanging on (or from) the tree.

But. . .

There is a whole flock of birds in the tree.

My frisbee got stuck in the tree.

We are climbing in (or on) the tree.

A cat is stuck in the tree.