def _decorate_tree(t, series):
    """ Attaches some default values on the tree for plotting.

    Parameters
    ----------
    t: skbio.TreeNode
        Input tree
    series: pd.Series
        Input pandas series

    """
    for i, n in enumerate(t.postorder()):
        n.size = 30
        if n.is_root():
            n.size = 50
        elif n.name == n.parent.children[0].name:
            n.color = '#00FF00'  # left child is green
        else:
            n.color = '#FF0000'  # right child is red
        if not n.is_tip():
            t.length = series.loc[n.name]
    return t