Sub SplitTables()
Application.ScreenUpdating = False
Const StrFnd As String = "Tree Number"
With ActiveDocument.Range
  With .Find
    .ClearFormatting
    .Replacement.ClearFormatting
    .Text = StrFnd
    .Replacement.Text = ""
    .Forward = True
    .Wrap = wdFindStop
    .Format = False
    .MatchCase = True
  End With
  Do While .Find.Execute
    If .Information(wdWithInTable) = True Then
      With .Cells(1)
        If .RowIndex > 1 Then
          If Split(.Range.Text, vbCr)(0) = StrFnd Then .Range.InsertBreak (wdColumnBreak)
        End If
      End With
    End If
    .Collapse wdCollapseEnd
  Loop
End With
Application.ScreenUpdating = True
End Sub