TreeStore with Root from Json, how?

Is it possible to define an empty TreeStore without a root: {} config and use a node from JSON as root?

I can't get it to work properly without a static root defined in the TreeStore.

It's working and the static root node is hidden, but I can't see why I needs to be there.

Here is the JSON I would like to use for my Tree. (My Root should be the root node).

Code:

{
    "data": {
        "id": 0,
        "name": "My Root",
        "expanded": true,
        "data": [
            {
                "id": 5,
                "name": "Test 1",
                "data": [
                    {
                        "id": 6,
                        "name": "Sub Folder",
                        "loaded": true
                    }
                ]
            },
            {
                "id": 7,
                "name": "Test 2",
                "loaded": true
            },
            {
                "id": 8,
                "name": "Test 3",
                "loaded": true
            }
        ]
    }
}

TreeStore with Root from Json, how?