diff --git a/artiq/dashboard/moninj.py b/artiq/dashboard/moninj.py
index db8bb78b7..b8e67129f 100644
--- a/artiq/dashboard/moninj.py
+++ b/artiq/dashboard/moninj.py
@@ -819,6 +819,48 @@ class _DeviceManager:
             await self.mi_connection.close()
 
 
+class MoninjTree(QtWidgets.QTreeWidget):
+    def __init__(self):
+        QtWidgets.QTreeWidget.__init__(self)
+        self.setDragDropMode(QtWidgets.QAbstractItemView.InternalMove)
+        self._groups = dict()
+        self._widgets = dict()
+
+    def add_widget(self, widget, group=None):
+        item = QtWidgets.QTreeWidgetItem([widget.to_model_path()])
+        self.setItemWidget(item, widget)
+        self._widgets[widget.to_model_path()] = widget
+        if group is not None:
+            self._get_group(group).addChild(item)
+        else:
+            self.addTopLevelItem(item)
+
+    def remove_widget(self, item):
+        widget = self.itemWidget(child, 0)
+        self.removeItemWidget(child, 0)
+        del self._widgets[widget.to_model_path()]
+        widget.deleteLater()
+
+    def add_group(self, group=None):
+        if group in self._groups:
+            raise SyntaxError("group name repeated")
+        group_item = QtWidgets.QTreeWidgetItem([group])
+        self.addTopLevelItem(group_item)
+        self._groups[group] = group_item
+        return group_item
+
+    def remove_group(self, group):
+        group_item = self._groups[group]
+        child_items = group_item.takeChildren()
+        for child in child_items:
+            self.remove_widget(child)
+        self.takeTopLevelItem(self.indexOfTopLevelItem(group_item))
+        del self._groups[group]
+
+    def _get_group(self, group):
+        return self._groups[group]
+
+
 class MonInjDock(QtWidgets.QDockWidget):
     def __init__(self, schedule_ctl):
         QtWidgets.QDockWidget.__init__(self, "MonInj")