public function saving(Tree $model)
    {
        if (!$model->exists and !in_array('path', array_keys($model->attributesToArray()), TRUE)) {
            $model->{$model->getTreeColumn('path')}   = '';
            $model->{$model->getTreeColumn('parent')} = NULL;
            $model->{$model->getTreeColumn('level')}  = 0;
        }
    }