{% load sitetree %}
<ul class="nav nav-pills nav-stacked">
    {% for item in sitetree_items %}
        <li {% if item.is_current or item.in_current_branch %}class="active"{% endif %}>
            <a href="{% sitetree_url for item %}">{{ item.title_resolved }}</a>
        </li>
    {% endfor %}
</ul>